diff --git a/toolchain/lower/aggregate.cpp b/toolchain/lower/aggregate.cpp
index 2cbd416964c6..5c6d410d8af7 100644
--- a/toolchain/lower/aggregate.cpp
+++ b/toolchain/lower/aggregate.cpp
@@ -154,13 +154,14 @@ auto EmitAggregateValueRepr(FunctionContext& context,
     }
 
     case SemIR::ValueRepr::Pointer: {
-      auto* llvm_value_rep_type = context.GetType(GetPointeeType(value_type));
+      auto pointee_type = GetPointeeType(value_type);
 
       // Write the value representation to a local alloca so we can produce a
       // pointer to it as the value representation of the struct or tuple.
-      auto* alloca = context.builder().CreateAlloca(llvm_value_rep_type);
+      auto* alloca = context.CreateAlloca(pointee_type);
       for (auto [i, ref_id] :
            llvm::enumerate(context.sem_ir().inst_blocks().Get(refs_id))) {
+        auto* llvm_value_rep_type = context.GetType(pointee_type);
         context.StoreObject(
             context.GetValueRepr(context.GetTypeIdOfInst(ref_id)).type(),
             context.GetValue(ref_id),
diff --git a/toolchain/lower/file_context.h b/toolchain/lower/file_context.h
index e565d595b4c6..e1b9a7e08e10 100644
--- a/toolchain/lower/file_context.h
+++ b/toolchain/lower/file_context.h
@@ -103,6 +103,15 @@ class FileContext {
     return GetTypeAndDIType(type_id).llvm_ir_type;
   }
 
+  // Returns the alignment of the given type_id. This adds the alignment to the
+  // fingerprint.
+  auto GetAlignment(SemIR::TypeId type_id) -> llvm::Align {
+    return llvm::Align(sem_ir()
+                           .types()
+                           .GetCompleteTypeInfo(type_id)
+                           .object_layout.alignment.bytes());
+  }
+
   // Returns both the lowered llvm IR type and the lowered llvm IR debug info
   // type for the given type_id.
   auto GetTypeAndDIType(SemIR::TypeId type_id) const -> LoweredTypes {
diff --git a/toolchain/lower/function_context.cpp b/toolchain/lower/function_context.cpp
index 154eb174d1ee..d32a99ca2267 100644
--- a/toolchain/lower/function_context.cpp
+++ b/toolchain/lower/function_context.cpp
@@ -201,7 +201,7 @@ auto FunctionContext::MakeSyntheticBlock() -> llvm::BasicBlock* {
   return synthetic_block_;
 }
 
-auto FunctionContext::CreateAlloca(llvm::Type* type, const llvm::Twine& name)
+auto FunctionContext::CreateAlloca(TypeInFile type, const llvm::Twine& name)
     -> llvm::AllocaInst* {
   // Position the first alloca right before the start of the executable code in
   // the function.
@@ -221,9 +221,8 @@ auto FunctionContext::CreateAlloca(llvm::Type* type, const llvm::Twine& name)
     builder().SetCurrentDebugLocation(debug_loc);
 
     // Create an alloca for this variable in the entry block.
-    // TODO: Compute alignment of the type, which may be greater than the
-    // alignment computed by LLVM.
-    alloca = builder().CreateAlloca(type, /*ArraySize=*/nullptr, name);
+    alloca = builder().CreateAlloca(GetType(type), /*ArraySize=*/nullptr, name);
+    alloca->setAlignment(GetAlignment(type));
   }
 
   // Create a lifetime start intrinsic here to indicate where its scope really
@@ -345,9 +344,11 @@ auto FunctionContext::LoadObject(TypeInFile type, llvm::Value* addr,
   auto* llvm_type = GetType(type);
   auto* load_type = GetWidenedMemoryType(llvm_type);
 
-  // TODO: Include alias and alignment information.
-  llvm::Value* value = builder().CreateLoad(load_type, addr, name);
+  // TODO: Include alias information.
+  auto* load = builder().CreateLoad(load_type, addr, name);
+  load->setAlignment(GetAlignment(type));
 
+  llvm::Value* value = load;
   if (load_type != llvm_type) {
     value = builder().CreateTrunc(value, llvm_type);
   }
@@ -356,7 +357,6 @@ auto FunctionContext::LoadObject(TypeInFile type, llvm::Value* addr,
 
 auto FunctionContext::StoreObject(TypeInFile type, llvm::Value* value,
                                   llvm::Value* addr) -> void {
-  // TODO: Include alias and alignment information.
   auto* llvm_type = GetType(type);
   CARBON_CHECK(value->getType() == llvm_type);
 
@@ -367,7 +367,9 @@ auto FunctionContext::StoreObject(TypeInFile type, llvm::Value* value,
     value = builder().CreateZExt(value, store_type);
   }
 
-  builder().CreateStore(value, addr);
+  // TODO: Include alias information.
+  auto* store = builder().CreateStore(value, addr);
+  store->setAlignment(GetAlignment(type));
 }
 
 auto FunctionContext::CopyValue(TypeInFile type, SemIR::InstId source_id,
@@ -394,9 +396,7 @@ auto FunctionContext::CopyObject(TypeInFile type, SemIR::InstId source_id,
                                  SemIR::InstId dest_id) -> void {
   const auto& layout = llvm_module().getDataLayout();
   auto* llvm_type = GetType(type);
-  // TODO: Compute known alignment of the source and destination, which may
-  // be greater than the alignment computed by LLVM.
-  auto align = layout.getABITypeAlign(llvm_type);
+  auto align = GetAlignment(type);
 
   // TODO: Attach !tbaa.struct metadata indicating which portions of the
   // type we actually need to copy and which are padding.
diff --git a/toolchain/lower/function_context.h b/toolchain/lower/function_context.h
index 923c39cc01c1..4d7fe15df2d6 100644
--- a/toolchain/lower/function_context.h
+++ b/toolchain/lower/function_context.h
@@ -127,6 +127,14 @@ class FunctionContext {
     return llvm_type;
   }
 
+  // Returns the alignment of the given type_id. This adds the alignment to the
+  // fingerprint.
+  auto GetAlignment(TypeInFile type) -> llvm::Align {
+    auto align = GetFileContext(type.file).GetAlignment(type.type_id);
+    AddIntToCurrentFingerprint(align.value());
+    return align;
+  }
+
   // Returns the type of the given instruction in the current specific.
   auto GetTypeOfInst(SemIR::InstId inst_id) -> llvm::Type* {
     return GetType(GetTypeIdOfInst(inst_id));
@@ -166,7 +174,7 @@ class FunctionContext {
 
   // Creates an alloca instruction of the given type, adds it to the entry
   // block, and starts the lifetime of the corresponding storage.
-  auto CreateAlloca(llvm::Type* type, const llvm::Twine& name = llvm::Twine())
+  auto CreateAlloca(TypeInFile type, const llvm::Twine& name = llvm::Twine())
       -> llvm::AllocaInst*;
 
   // Returns the debug location to associate with the specified instruction.
diff --git a/toolchain/lower/handle.cpp b/toolchain/lower/handle.cpp
index 2ec38953794d..b84c47f708bd 100644
--- a/toolchain/lower/handle.cpp
+++ b/toolchain/lower/handle.cpp
@@ -393,7 +393,7 @@ auto HandleInst(FunctionContext& context, SemIR::InstId inst_id,
 auto HandleInst(FunctionContext& context, SemIR::InstId inst_id,
                 SemIR::VarStorage /* inst */) -> void {
   context.SetLocal(inst_id,
-                   context.CreateAlloca(context.GetTypeOfInst(inst_id)));
+                   context.CreateAlloca(context.GetTypeIdOfInst(inst_id)));
 }
 
 }  // namespace Carbon::Lower
diff --git a/toolchain/lower/handle_expr_category.cpp b/toolchain/lower/handle_expr_category.cpp
index 37e32bb5fc3c..012e27a890cb 100644
--- a/toolchain/lower/handle_expr_category.cpp
+++ b/toolchain/lower/handle_expr_category.cpp
@@ -56,7 +56,7 @@ auto HandleInst(FunctionContext& context, SemIR::InstId inst_id,
 auto HandleInst(FunctionContext& context, SemIR::InstId inst_id,
                 SemIR::TemporaryStorage /*inst*/) -> void {
   context.SetLocal(
-      inst_id, context.CreateAlloca(context.GetTypeOfInst(inst_id), "temp"));
+      inst_id, context.CreateAlloca(context.GetTypeIdOfInst(inst_id), "temp"));
 }
 
 auto HandleInst(FunctionContext& context, SemIR::InstId inst_id,
diff --git a/toolchain/lower/testdata/array/array_in_place.carbon b/toolchain/lower/testdata/array/array_in_place.carbon
index bdab9f2c1029..4d74d1b7b99c 100644
--- a/toolchain/lower/testdata/array/array_in_place.carbon
+++ b/toolchain/lower/testdata/array/array_in_place.carbon
@@ -24,7 +24,7 @@ fn G() {
 // CHECK:STDOUT: ; Function Attrs: nounwind
 // CHECK:STDOUT: define void @_CG.Main() #0 !dbg !4 {
 // CHECK:STDOUT: entry:
-// CHECK:STDOUT:   %_.var = alloca [2 x { i32, i32, i32 }], align 8, !dbg !7
+// CHECK:STDOUT:   %_.var = alloca [2 x { i32, i32, i32 }], align 4, !dbg !7
 // CHECK:STDOUT:   call void @llvm.lifetime.start.p0(ptr %_.var), !dbg !7
 // CHECK:STDOUT:   %.loc16_47.6.array.index = getelementptr inbounds [2 x { i32, i32, i32 }], ptr %_.var, i32 0, i64 0, !dbg !8
 // CHECK:STDOUT:   call void @_CF.Main(ptr %.loc16_47.6.array.index), !dbg !9
diff --git a/toolchain/lower/testdata/array/assign_return_value.carbon b/toolchain/lower/testdata/array/assign_return_value.carbon
index 070a38aea4f1..daa7313055fd 100644
--- a/toolchain/lower/testdata/array/assign_return_value.carbon
+++ b/toolchain/lower/testdata/array/assign_return_value.carbon
@@ -34,7 +34,7 @@ fn Run() {
 // CHECK:STDOUT: define i32 @main() #0 !dbg !10 {
 // CHECK:STDOUT: entry:
 // CHECK:STDOUT:   %_.var = alloca [2 x i32], align 4, !dbg !14
-// CHECK:STDOUT:   %.loc16_28.1.temp = alloca { i32, i32 }, align 8, !dbg !15
+// CHECK:STDOUT:   %.loc16_28.1.temp = alloca { i32, i32 }, align 4, !dbg !15
 // CHECK:STDOUT:   call void @llvm.lifetime.start.p0(ptr %_.var), !dbg !14
 // CHECK:STDOUT:   call void @llvm.lifetime.start.p0(ptr %.loc16_28.1.temp), !dbg !15
 // CHECK:STDOUT:   call void @_CF.Main(ptr %.loc16_28.1.temp), !dbg !15
diff --git a/toolchain/lower/testdata/array/base.carbon b/toolchain/lower/testdata/array/base.carbon
index b56d96601b0b..bc2303d8753b 100644
--- a/toolchain/lower/testdata/array/base.carbon
+++ b/toolchain/lower/testdata/array/base.carbon
@@ -31,8 +31,8 @@ fn Run() {
 // CHECK:STDOUT: entry:
 // CHECK:STDOUT:   %_.var.loc14 = alloca [1 x i32], align 4, !dbg !8
 // CHECK:STDOUT:   %_.var.loc15 = alloca [2 x double], align 8, !dbg !9
-// CHECK:STDOUT:   %_.var.loc16 = alloca [5 x {}], align 8, !dbg !10
-// CHECK:STDOUT:   %d.var = alloca { i32, i32, i32 }, align 8, !dbg !11
+// CHECK:STDOUT:   %_.var.loc16 = alloca [5 x {}], align 1, !dbg !10
+// CHECK:STDOUT:   %d.var = alloca { i32, i32, i32 }, align 4, !dbg !11
 // CHECK:STDOUT:   %_.var.loc18 = alloca [3 x i32], align 4, !dbg !12
 // CHECK:STDOUT:   call void @llvm.lifetime.start.p0(ptr %_.var.loc14), !dbg !8
 // CHECK:STDOUT:   %.loc14_29.3.array.index = getelementptr inbounds [1 x i32], ptr %_.var.loc14, i32 0, i64 0, !dbg !13
diff --git a/toolchain/lower/testdata/array/iterate.carbon b/toolchain/lower/testdata/array/iterate.carbon
index c3c6403b7f47..320f2b98f65f 100644
--- a/toolchain/lower/testdata/array/iterate.carbon
+++ b/toolchain/lower/testdata/array/iterate.carbon
@@ -32,7 +32,7 @@ fn F() {
 // CHECK:STDOUT: entry:
 // CHECK:STDOUT:   %.loc16_43.3.temp = alloca [6 x i32], align 4, !dbg !7
 // CHECK:STDOUT:   %var = alloca i32, align 4, !dbg !8
-// CHECK:STDOUT:   %.loc17_19.1.temp = alloca <{ i32, i1 }>, align 8, !dbg !8
+// CHECK:STDOUT:   %.loc17_19.1.temp = alloca <{ i32, i1 }>, align 4, !dbg !8
 // CHECK:STDOUT:   call void @llvm.lifetime.start.p0(ptr %.loc16_43.3.temp), !dbg !7
 // CHECK:STDOUT:   %.loc16_43.4.array.index = getelementptr inbounds [6 x i32], ptr %.loc16_43.3.temp, i32 0, i64 0, !dbg !7
 // CHECK:STDOUT:   %.loc16_43.7.array.index = getelementptr inbounds [6 x i32], ptr %.loc16_43.3.temp, i32 0, i64 1, !dbg !7
diff --git a/toolchain/lower/testdata/array/layout.carbon b/toolchain/lower/testdata/array/layout.carbon
index 109b952345f2..55e6e041b858 100644
--- a/toolchain/lower/testdata/array/layout.carbon
+++ b/toolchain/lower/testdata/array/layout.carbon
@@ -123,7 +123,7 @@ var c: array(Core.Int(257), 5) = (1, 2, 3, 4, 5);
 // CHECK:STDOUT: ; Function Attrs: nounwind
 // CHECK:STDOUT: define internal void @_C__global_init.Main() #0 !dbg !4 {
 // CHECK:STDOUT: entry:
-// CHECK:STDOUT:   call void @llvm.memcpy.p0.p0.i64(ptr align 1 @_Cc.Main, ptr align 1 @array.loc3_1, i64 320, i1 false), !dbg !7
+// CHECK:STDOUT:   call void @llvm.memcpy.p0.p0.i64(ptr align 32 @_Cc.Main, ptr align 32 @array.loc3_1, i64 320, i1 false), !dbg !7
 // CHECK:STDOUT:   ret void, !dbg !8
 // CHECK:STDOUT: }
 // CHECK:STDOUT:
diff --git a/toolchain/lower/testdata/builtins/cpp.carbon b/toolchain/lower/testdata/builtins/cpp.carbon
index d4d7d444948b..53c7b6a9371f 100644
--- a/toolchain/lower/testdata/builtins/cpp.carbon
+++ b/toolchain/lower/testdata/builtins/cpp.carbon
@@ -54,9 +54,9 @@ fn Test() {
 // CHECK:STDOUT: ; Function Attrs: nounwind
 // CHECK:STDOUT: define void @_CTest.Main() #0 !dbg !11 {
 // CHECK:STDOUT: entry:
-// CHECK:STDOUT:   %.loc25_53.1.temp = alloca [16 x i8], align 1, !dbg !14
+// CHECK:STDOUT:   %.loc25_53.1.temp = alloca [16 x i8], align 8, !dbg !14
 // CHECK:STDOUT:   %.loc25_52.3.temp = alloca [4 x i32], align 4, !dbg !15
-// CHECK:STDOUT:   %.loc26_47.1.temp = alloca [16 x i8], align 1, !dbg !16
+// CHECK:STDOUT:   %.loc26_47.1.temp = alloca [16 x i8], align 8, !dbg !16
 // CHECK:STDOUT:   %.loc26_46.3.temp = alloca [4 x i32], align 4, !dbg !17
 // CHECK:STDOUT:   call void @llvm.lifetime.start.p0(ptr %.loc25_53.1.temp), !dbg !14
 // CHECK:STDOUT:   call void @llvm.lifetime.start.p0(ptr %.loc25_52.3.temp), !dbg !15
diff --git a/toolchain/lower/testdata/builtins/no_op.carbon b/toolchain/lower/testdata/builtins/no_op.carbon
index 2627b09d5aea..aacfb3cf1765 100644
--- a/toolchain/lower/testdata/builtins/no_op.carbon
+++ b/toolchain/lower/testdata/builtins/no_op.carbon
@@ -45,7 +45,7 @@ fn J() {
 // CHECK:STDOUT: ; Function Attrs: nounwind
 // CHECK:STDOUT: define void @_CG.Main() #0 !dbg !8 {
 // CHECK:STDOUT: entry:
-// CHECK:STDOUT:   %a.var = alloca {}, align 8, !dbg !9
+// CHECK:STDOUT:   %a.var = alloca {}, align 1, !dbg !9
 // CHECK:STDOUT:   call void @llvm.lifetime.start.p0(ptr %a.var), !dbg !9
 // CHECK:STDOUT:   ret void, !dbg !10
 // CHECK:STDOUT: }
@@ -61,7 +61,7 @@ fn J() {
 // CHECK:STDOUT: ; Function Attrs: nounwind
 // CHECK:STDOUT: define void @_CJ.Main() #0 !dbg !13 {
 // CHECK:STDOUT: entry:
-// CHECK:STDOUT:   %.loc33_11.1.temp = alloca {}, align 8, !dbg !14
+// CHECK:STDOUT:   %.loc33_11.1.temp = alloca {}, align 1, !dbg !14
 // CHECK:STDOUT:   call void @_CI.Main(), !dbg !14
 // CHECK:STDOUT:   call void @llvm.lifetime.start.p0(ptr %.loc33_11.1.temp), !dbg !14
 // CHECK:STDOUT:   ret void, !dbg !15
diff --git a/toolchain/lower/testdata/class/adapt.carbon b/toolchain/lower/testdata/class/adapt.carbon
index 0a7b5615c041..29d14203346d 100644
--- a/toolchain/lower/testdata/class/adapt.carbon
+++ b/toolchain/lower/testdata/class/adapt.carbon
@@ -89,7 +89,7 @@ fn DoStuff(a: Int) -> Int {
 // CHECK:STDOUT: ; Function Attrs: nounwind
 // CHECK:STDOUT: define i32 @_CUse.Main() #0 !dbg !21 {
 // CHECK:STDOUT: entry:
-// CHECK:STDOUT:   %pa.var = alloca { i32, i32 }, align 8, !dbg !24
+// CHECK:STDOUT:   %pa.var = alloca { i32, i32 }, align 4, !dbg !24
 // CHECK:STDOUT:   call void @llvm.lifetime.start.p0(ptr %pa.var), !dbg !24
 // CHECK:STDOUT:   call void @_CMake.PairAdapter.Main(ptr %pa.var), !dbg !25
 // CHECK:STDOUT:   %PairAdapter.GetB.call = call i32 @_CGetB.PairAdapter.Main(ptr %pa.var), !dbg !26
diff --git a/toolchain/lower/testdata/class/convert.carbon b/toolchain/lower/testdata/class/convert.carbon
index d7656d241a8a..a9a07a44a79a 100644
--- a/toolchain/lower/testdata/class/convert.carbon
+++ b/toolchain/lower/testdata/class/convert.carbon
@@ -47,7 +47,7 @@ fn DoIt() {
 // CHECK:STDOUT: ; Function Attrs: nounwind
 // CHECK:STDOUT: define void @_CDoIt.Main() #0 !dbg !19 {
 // CHECK:STDOUT: entry:
-// CHECK:STDOUT:   %w.var = alloca { i32 }, align 8, !dbg !22
+// CHECK:STDOUT:   %w.var = alloca { i32 }, align 4, !dbg !22
 // CHECK:STDOUT:   call void @llvm.lifetime.start.p0(ptr %w.var), !dbg !22
 // CHECK:STDOUT:   %.loc24_31.3.n = getelementptr inbounds nuw { i32 }, ptr %w.var, i32 0, i32 0, !dbg !23
 // CHECK:STDOUT:   call void @llvm.memcpy.p0.p0.i64(ptr align 4 %w.var, ptr align 4 @IntWrapper.val.loc24_3, i64 4, i1 false), !dbg !22
diff --git a/toolchain/lower/testdata/class/field.carbon b/toolchain/lower/testdata/class/field.carbon
index 5a9e49db3e09..20d45c7a9ba0 100644
--- a/toolchain/lower/testdata/class/field.carbon
+++ b/toolchain/lower/testdata/class/field.carbon
@@ -168,7 +168,7 @@ fn Run() {
 // CHECK:STDOUT: ; Function Attrs: nounwind
 // CHECK:STDOUT: define i32 @main() #0 !dbg !4 {
 // CHECK:STDOUT: entry:
-// CHECK:STDOUT:   %o.var = alloca {}, align 8, !dbg !8
+// CHECK:STDOUT:   %o.var = alloca {}, align 1, !dbg !8
 // CHECK:STDOUT:   %_.var = alloca { ptr, {} }, align 8, !dbg !9
 // CHECK:STDOUT:   call void @llvm.lifetime.start.p0(ptr %o.var), !dbg !8
 // CHECK:STDOUT:   call void @llvm.lifetime.start.p0(ptr %_.var), !dbg !9
@@ -249,7 +249,7 @@ fn Run() {
 // CHECK:STDOUT: ; Function Attrs: nounwind
 // CHECK:STDOUT: define i32 @main() #0 !dbg !4 {
 // CHECK:STDOUT: entry:
-// CHECK:STDOUT:   %o.var = alloca { i32 }, align 8, !dbg !8
+// CHECK:STDOUT:   %o.var = alloca { i32 }, align 4, !dbg !8
 // CHECK:STDOUT:   %_.var = alloca <{ ptr, { i32 } }>, align 8, !dbg !9
 // CHECK:STDOUT:   call void @llvm.lifetime.start.p0(ptr %o.var), !dbg !8
 // CHECK:STDOUT:   call void @llvm.lifetime.start.p0(ptr %_.var), !dbg !9
diff --git a/toolchain/lower/testdata/class/generic.carbon b/toolchain/lower/testdata/class/generic.carbon
index 8e61cc53e6db..df1682957bfc 100644
--- a/toolchain/lower/testdata/class/generic.carbon
+++ b/toolchain/lower/testdata/class/generic.carbon
@@ -290,7 +290,7 @@ fn AccessTuple() -> (i32, i32, i32) {
 // CHECK:STDOUT: ; Function Attrs: nounwind
 // CHECK:STDOUT: define i1 @_CAccessBool.Main() #0 !dbg !4 {
 // CHECK:STDOUT: entry:
-// CHECK:STDOUT:   %c.var = alloca { i1, i32 }, align 8, !dbg !8
+// CHECK:STDOUT:   %c.var = alloca { i1, i32 }, align 4, !dbg !8
 // CHECK:STDOUT:   call void @llvm.lifetime.start.p0(ptr %c.var), !dbg !8
 // CHECK:STDOUT:   %.loc16_37.2.v = getelementptr inbounds nuw { i1, i32 }, ptr %c.var, i32 0, i32 0, !dbg !9
 // CHECK:STDOUT:   %.loc16_37.5.w = getelementptr inbounds nuw { i1, i32 }, ptr %c.var, i32 0, i32 1, !dbg !9
@@ -321,7 +321,7 @@ fn AccessTuple() -> (i32, i32, i32) {
 // CHECK:STDOUT: ; Function Attrs: nounwind
 // CHECK:STDOUT: define i32 @_CAccessInt.Main() #0 !dbg !29 {
 // CHECK:STDOUT: entry:
-// CHECK:STDOUT:   %c.var = alloca { i1, i32 }, align 8, !dbg !32
+// CHECK:STDOUT:   %c.var = alloca { i1, i32 }, align 4, !dbg !32
 // CHECK:STDOUT:   call void @llvm.lifetime.start.p0(ptr %c.var), !dbg !32
 // CHECK:STDOUT:   %.loc21_37.2.v = getelementptr inbounds nuw { i1, i32 }, ptr %c.var, i32 0, i32 0, !dbg !33
 // CHECK:STDOUT:   %.loc21_37.5.w = getelementptr inbounds nuw { i1, i32 }, ptr %c.var, i32 0, i32 1, !dbg !33
@@ -334,7 +334,7 @@ fn AccessTuple() -> (i32, i32, i32) {
 // CHECK:STDOUT: ; Function Attrs: nounwind
 // CHECK:STDOUT: define void @_CAccessEmpty.Main() #0 !dbg !36 {
 // CHECK:STDOUT: entry:
-// CHECK:STDOUT:   %c.var = alloca { i1, {} }, align 8, !dbg !39
+// CHECK:STDOUT:   %c.var = alloca { i1, {} }, align 1, !dbg !39
 // CHECK:STDOUT:   call void @llvm.lifetime.start.p0(ptr %c.var), !dbg !39
 // CHECK:STDOUT:   %.loc26_37.2.v = getelementptr inbounds nuw { i1, {} }, ptr %c.var, i32 0, i32 0, !dbg !40
 // CHECK:STDOUT:   %.loc26_37.4.w = getelementptr inbounds nuw { i1, {} }, ptr %c.var, i32 0, i32 1, !dbg !40
@@ -359,7 +359,7 @@ fn AccessTuple() -> (i32, i32, i32) {
 // CHECK:STDOUT: ; Function Attrs: nounwind
 // CHECK:STDOUT: define void @_CAccessTuple.Main(ptr sret({ i32, i32, i32 }) %return) #0 !dbg !51 {
 // CHECK:STDOUT: entry:
-// CHECK:STDOUT:   %c.var = alloca { i1, { i32, i32, i32 } }, align 8, !dbg !52
+// CHECK:STDOUT:   %c.var = alloca { i1, { i32, i32, i32 } }, align 4, !dbg !52
 // CHECK:STDOUT:   call void @llvm.lifetime.start.p0(ptr %c.var), !dbg !52
 // CHECK:STDOUT:   %.loc31_57.2.v = getelementptr inbounds nuw { i1, { i32, i32, i32 } }, ptr %c.var, i32 0, i32 0, !dbg !53
 // CHECK:STDOUT:   %.loc31_57.4.w = getelementptr inbounds nuw { i1, { i32, i32, i32 } }, ptr %c.var, i32 0, i32 1, !dbg !53
diff --git a/toolchain/lower/testdata/class/value_access.carbon b/toolchain/lower/testdata/class/value_access.carbon
index d0473a082835..4352396e22d0 100644
--- a/toolchain/lower/testdata/class/value_access.carbon
+++ b/toolchain/lower/testdata/class/value_access.carbon
@@ -27,6 +27,7 @@ fn F(c: C) -> i32 {
 // CHECK:STDOUT: ; Function Attrs: nounwind
 // CHECK:STDOUT: define i32 @_CF.Main(ptr %c) #0 !dbg !4 {
 // CHECK:STDOUT: entry:
+// CHECK:STDOUT:   %tuple = alloca { i32, i32, i32 }, align 4, !dbg !11
 // CHECK:STDOUT:   %.loc21_11.1.a = getelementptr inbounds nuw { { i32, i32, i32 } }, ptr %c, i32 0, i32 0, !dbg !11
 // CHECK:STDOUT:   %tuple.elem0.tuple.elem = getelementptr inbounds nuw { i32, i32, i32 }, ptr %.loc21_11.1.a, i32 0, i32 0, !dbg !11
 // CHECK:STDOUT:   %.loc21_11.2 = load i32, ptr %tuple.elem0.tuple.elem, align 4, !dbg !11
@@ -34,7 +35,7 @@ fn F(c: C) -> i32 {
 // CHECK:STDOUT:   %.loc21_11.3 = load i32, ptr %tuple.elem1.loc21_11.tuple.elem, align 4, !dbg !11
 // CHECK:STDOUT:   %tuple.elem2.tuple.elem = getelementptr inbounds nuw { i32, i32, i32 }, ptr %.loc21_11.1.a, i32 0, i32 2, !dbg !11
 // CHECK:STDOUT:   %.loc21_11.4 = load i32, ptr %tuple.elem2.tuple.elem, align 4, !dbg !11
-// CHECK:STDOUT:   %tuple = alloca { i32, i32, i32 }, align 8, !dbg !11
+// CHECK:STDOUT:   call void @llvm.lifetime.start.p0(ptr %tuple), !dbg !11
 // CHECK:STDOUT:   %tuple1 = getelementptr inbounds nuw { i32, i32, i32 }, ptr %tuple, i32 0, i32 0, !dbg !11
 // CHECK:STDOUT:   store i32 %.loc21_11.2, ptr %tuple1, align 4, !dbg !11
 // CHECK:STDOUT:   %tuple2 = getelementptr inbounds nuw { i32, i32, i32 }, ptr %tuple, i32 0, i32 1, !dbg !11
@@ -46,7 +47,11 @@ fn F(c: C) -> i32 {
 // CHECK:STDOUT:   ret i32 %tuple.elem1.loc21_13.tuple.elem.load, !dbg !12
 // CHECK:STDOUT: }
 // CHECK:STDOUT:
+// CHECK:STDOUT: ; Function Attrs: nocallback nofree nosync nounwind willreturn memory(argmem: readwrite)
+// CHECK:STDOUT: declare void @llvm.lifetime.start.p0(ptr captures(none)) #1
+// CHECK:STDOUT:
 // CHECK:STDOUT: attributes #0 = { nounwind }
+// CHECK:STDOUT: attributes #1 = { nocallback nofree nosync nounwind willreturn memory(argmem: readwrite) }
 // CHECK:STDOUT:
 // CHECK:STDOUT: !llvm.module.flags = !{!0, !1}
 // CHECK:STDOUT: !llvm.dbg.cu = !{!2}
diff --git a/toolchain/lower/testdata/class/virtual.carbon b/toolchain/lower/testdata/class/virtual.carbon
index a20e7d6d1329..3b0e3ce48341 100644
--- a/toolchain/lower/testdata/class/virtual.carbon
+++ b/toolchain/lower/testdata/class/virtual.carbon
@@ -262,7 +262,7 @@ fn Use() {
 // CHECK:STDOUT: ; Function Attrs: nounwind
 // CHECK:STDOUT: define void @_CCreate.Create() #0 !dbg !4 {
 // CHECK:STDOUT: entry:
-// CHECK:STDOUT:   %_.var.loc7 = alloca {}, align 8, !dbg !7
+// CHECK:STDOUT:   %_.var.loc7 = alloca {}, align 1, !dbg !7
 // CHECK:STDOUT:   %_.var.loc8 = alloca { ptr, {} }, align 8, !dbg !8
 // CHECK:STDOUT:   %_.var.loc9 = alloca { { ptr, {} } }, align 8, !dbg !9
 // CHECK:STDOUT:   %_.var.loc12 = alloca { { ptr, {} } }, align 8, !dbg !10
@@ -528,7 +528,7 @@ fn Use() {
 // CHECK:STDOUT:   call void @llvm.lifetime.start.p0(ptr %_.var), !dbg !16
 // CHECK:STDOUT:   %.loc13_24.2.vptr = getelementptr inbounds nuw <{ ptr, i32 }>, ptr %_.var, i32 0, i32 0, !dbg !20
 // CHECK:STDOUT:   %.loc13_24.5.m = getelementptr inbounds nuw <{ ptr, i32 }>, ptr %_.var, i32 0, i32 1, !dbg !20
-// CHECK:STDOUT:   call void @llvm.memcpy.p0.p0.i64(ptr align 1 %_.var, ptr align 1 @Base.val.loc13_3, i64 12, i1 false), !dbg !16
+// CHECK:STDOUT:   call void @llvm.memcpy.p0.p0.i64(ptr align 8 %_.var, ptr align 8 @Base.val.loc13_3, i64 12, i1 false), !dbg !16
 // CHECK:STDOUT:   call void @"_COp.c06798f3d09e8cc8:core.Destroy.Core"(ptr %_.var), !dbg !16
 // CHECK:STDOUT:   call void @"_COp.c06798f3d09e8cc8:core.Destroy.Core"(ptr %v.var), !dbg !15
 // CHECK:STDOUT:   call void @"_COp.94e3ca86614aba5d:core.Destroy.Core"(ptr %i.var), !dbg !14
@@ -907,7 +907,7 @@ fn Use() {
 // CHECK:STDOUT: ; Function Attrs: nounwind
 // CHECK:STDOUT: define linkonce_odr void @_CF.Base.Main.9ddc77f6d5c74933(ptr %self) #0 !dbg !39 {
 // CHECK:STDOUT: entry:
-// CHECK:STDOUT:   %_.var = alloca {}, align 8, !dbg !42
+// CHECK:STDOUT:   %_.var = alloca {}, align 1, !dbg !42
 // CHECK:STDOUT:   call void @llvm.lifetime.start.p0(ptr %_.var), !dbg !42
 // CHECK:STDOUT:   call void @"_COp.07a02b3c29b03141:core.Destroy.Core"(ptr %_.var), !dbg !42
 // CHECK:STDOUT:   ret void, !dbg !43
@@ -916,7 +916,7 @@ fn Use() {
 // CHECK:STDOUT: ; Function Attrs: nounwind
 // CHECK:STDOUT: define linkonce_odr void @_CF.Base.Main.dc3f1ae930f86538(ptr %self) #0 !dbg !44 {
 // CHECK:STDOUT: entry:
-// CHECK:STDOUT:   %_.var = alloca { {} }, align 8, !dbg !47
+// CHECK:STDOUT:   %_.var = alloca { {} }, align 1, !dbg !47
 // CHECK:STDOUT:   call void @llvm.lifetime.start.p0(ptr %_.var), !dbg !47
 // CHECK:STDOUT:   call void @"_COp.64de2e862a836f25:core.Destroy.Core"(ptr %_.var), !dbg !47
 // CHECK:STDOUT:   ret void, !dbg !48
@@ -1095,8 +1095,8 @@ fn Use() {
 // CHECK:STDOUT: ; Function Attrs: alwaysinline nounwind
 // CHECK:STDOUT: define void @"_CF:thunk:Base.Main:Derived.Main"(ptr sret({}) %return, ptr %self, ptr %n) #1 !dbg !12 {
 // CHECK:STDOUT: entry:
-// CHECK:STDOUT:   %.loc17_58.1.temp = alloca {}, align 8, !dbg !16
-// CHECK:STDOUT:   %.loc12_33.1.temp = alloca {}, align 8, !dbg !17
+// CHECK:STDOUT:   %.loc17_58.1.temp = alloca {}, align 1, !dbg !16
+// CHECK:STDOUT:   %.loc12_33.1.temp = alloca {}, align 1, !dbg !17
 // CHECK:STDOUT:   call void @llvm.lifetime.start.p0(ptr %.loc17_58.1.temp), !dbg !16
 // CHECK:STDOUT:   call void @llvm.lifetime.start.p0(ptr %.loc12_33.1.temp), !dbg !17
 // CHECK:STDOUT:   call void @"_CConvert.From.Main:ImplicitAs.9040cf91eef70a75.Core"(ptr %.loc12_33.1.temp, ptr %n), !dbg !17
@@ -1123,8 +1123,8 @@ fn Use() {
 // CHECK:STDOUT: define void @_CUse.Main() #0 !dbg !28 {
 // CHECK:STDOUT: entry:
 // CHECK:STDOUT:   %d.var = alloca { { ptr } }, align 8, !dbg !31
-// CHECK:STDOUT:   %.loc25_10.1.temp = alloca {}, align 8, !dbg !32
-// CHECK:STDOUT:   %.loc25_9.2.temp = alloca {}, align 8, !dbg !33
+// CHECK:STDOUT:   %.loc25_10.1.temp = alloca {}, align 1, !dbg !32
+// CHECK:STDOUT:   %.loc25_9.2.temp = alloca {}, align 1, !dbg !33
 // CHECK:STDOUT:   call void @llvm.lifetime.start.p0(ptr %d.var), !dbg !31
 // CHECK:STDOUT:   %.loc23_31.2.base = getelementptr inbounds nuw { { ptr } }, ptr %d.var, i32 0, i32 0, !dbg !34
 // CHECK:STDOUT:   %.loc23_30.2.vptr = getelementptr inbounds nuw { ptr }, ptr %.loc23_31.2.base, i32 0, i32 0, !dbg !35
diff --git a/toolchain/lower/testdata/for/bindings.carbon b/toolchain/lower/testdata/for/bindings.carbon
index f6192ac6882d..7bdc266ed0df 100644
--- a/toolchain/lower/testdata/for/bindings.carbon
+++ b/toolchain/lower/testdata/for/bindings.carbon
@@ -41,11 +41,11 @@ fn For() {
 // CHECK:STDOUT: ; Function Attrs: nounwind
 // CHECK:STDOUT: define void @_CFor.Main() #0 !dbg !4 {
 // CHECK:STDOUT: entry:
-// CHECK:STDOUT:   %r.var = alloca {}, align 8, !dbg !7
-// CHECK:STDOUT:   %var = alloca {}, align 8, !dbg !8
-// CHECK:STDOUT:   %.loc29_33.1.temp = alloca <{ { i32, i32 }, i1 }>, align 8, !dbg !8
+// CHECK:STDOUT:   %r.var = alloca {}, align 1, !dbg !7
+// CHECK:STDOUT:   %var = alloca {}, align 1, !dbg !8
+// CHECK:STDOUT:   %.loc29_33.1.temp = alloca <{ { i32, i32 }, i1 }>, align 4, !dbg !8
 // CHECK:STDOUT:   %n.var = alloca i32, align 4, !dbg !9
-// CHECK:STDOUT:   %.loc29_33.8.temp = alloca { i32, i32 }, align 8, !dbg !8
+// CHECK:STDOUT:   %.loc29_33.8.temp = alloca { i32, i32 }, align 4, !dbg !8
 // CHECK:STDOUT:   call void @llvm.lifetime.start.p0(ptr %r.var), !dbg !7
 // CHECK:STDOUT:   call void @llvm.memcpy.p0.p0.i64(ptr align 1 %r.var, ptr align 1 @EmptyRange.val.loc27_3, i64 0, i1 false), !dbg !7
 // CHECK:STDOUT:   call void @"_CNewCursor.EmptyRange.7920d9939e32908d.Main:Iterate.Core.9de724674fdcc2fc"(ptr %r.var), !dbg !8
diff --git a/toolchain/lower/testdata/for/break_continue.carbon b/toolchain/lower/testdata/for/break_continue.carbon
index 205762c5e065..04f0ba0e2416 100644
--- a/toolchain/lower/testdata/for/break_continue.carbon
+++ b/toolchain/lower/testdata/for/break_continue.carbon
@@ -36,9 +36,9 @@ fn For() {
 // CHECK:STDOUT: ; Function Attrs: nounwind
 // CHECK:STDOUT: define void @_CFor.Main() #0 !dbg !4 {
 // CHECK:STDOUT: entry:
-// CHECK:STDOUT:   %.loc20_32.1.temp = alloca { i32, i32 }, align 8, !dbg !7
+// CHECK:STDOUT:   %.loc20_32.1.temp = alloca { i32, i32 }, align 4, !dbg !7
 // CHECK:STDOUT:   %var = alloca i32, align 4, !dbg !8
-// CHECK:STDOUT:   %.loc20_33.1.temp = alloca <{ i32, i1 }>, align 8, !dbg !8
+// CHECK:STDOUT:   %.loc20_33.1.temp = alloca <{ i32, i1 }>, align 4, !dbg !8
 // CHECK:STDOUT:   call void @llvm.lifetime.start.p0(ptr %.loc20_32.1.temp), !dbg !7
 // CHECK:STDOUT:   call void @_CRange.Core(ptr %.loc20_32.1.temp, i32 100), !dbg !7
 // CHECK:STDOUT:   %IntRange.as.Iterate.impl.NewCursor.call = call i32 @"_CNewCursor.IntRange.9452f4c51951679b.Core:Iterate.Core.be1e879c1ad406d8"(ptr %.loc20_32.1.temp), !dbg !8
diff --git a/toolchain/lower/testdata/for/for.carbon b/toolchain/lower/testdata/for/for.carbon
index eff7c2782284..d58db871462c 100644
--- a/toolchain/lower/testdata/for/for.carbon
+++ b/toolchain/lower/testdata/for/for.carbon
@@ -36,9 +36,9 @@ fn For() {
 // CHECK:STDOUT: ; Function Attrs: nounwind
 // CHECK:STDOUT: define void @_CFor.Main() #0 !dbg !4 {
 // CHECK:STDOUT: entry:
-// CHECK:STDOUT:   %.loc21_32.1.temp = alloca { i32, i32 }, align 8, !dbg !7
+// CHECK:STDOUT:   %.loc21_32.1.temp = alloca { i32, i32 }, align 4, !dbg !7
 // CHECK:STDOUT:   %var = alloca i32, align 4, !dbg !8
-// CHECK:STDOUT:   %.loc21_33.1.temp = alloca <{ i32, i1 }>, align 8, !dbg !8
+// CHECK:STDOUT:   %.loc21_33.1.temp = alloca <{ i32, i1 }>, align 4, !dbg !8
 // CHECK:STDOUT:   call void @_CF.Main(), !dbg !9
 // CHECK:STDOUT:   call void @llvm.lifetime.start.p0(ptr %.loc21_32.1.temp), !dbg !7
 // CHECK:STDOUT:   call void @_CRange.Core(ptr %.loc21_32.1.temp, i32 100), !dbg !7
diff --git a/toolchain/lower/testdata/function/call/empty_struct.carbon b/toolchain/lower/testdata/function/call/empty_struct.carbon
index 0cdf8ab7f538..2f6dbf028198 100644
--- a/toolchain/lower/testdata/function/call/empty_struct.carbon
+++ b/toolchain/lower/testdata/function/call/empty_struct.carbon
@@ -30,7 +30,7 @@ fn Main() {
 // CHECK:STDOUT: ; Function Attrs: nounwind
 // CHECK:STDOUT: define void @_CMain.Main() #0 !dbg !8 {
 // CHECK:STDOUT: entry:
-// CHECK:STDOUT:   %_.var = alloca {}, align 8, !dbg !9
+// CHECK:STDOUT:   %_.var = alloca {}, align 1, !dbg !9
 // CHECK:STDOUT:   call void @llvm.lifetime.start.p0(ptr %_.var), !dbg !9
 // CHECK:STDOUT:   call void @_CEcho.Main(), !dbg !10
 // CHECK:STDOUT:   ret void, !dbg !11
diff --git a/toolchain/lower/testdata/function/call/empty_tuple.carbon b/toolchain/lower/testdata/function/call/empty_tuple.carbon
index 9aed5eb11d4e..28bc4431a411 100644
--- a/toolchain/lower/testdata/function/call/empty_tuple.carbon
+++ b/toolchain/lower/testdata/function/call/empty_tuple.carbon
@@ -30,7 +30,7 @@ fn Main() {
 // CHECK:STDOUT: ; Function Attrs: nounwind
 // CHECK:STDOUT: define void @_CMain.Main() #0 !dbg !8 {
 // CHECK:STDOUT: entry:
-// CHECK:STDOUT:   %_.var = alloca {}, align 8, !dbg !9
+// CHECK:STDOUT:   %_.var = alloca {}, align 1, !dbg !9
 // CHECK:STDOUT:   call void @llvm.lifetime.start.p0(ptr %_.var), !dbg !9
 // CHECK:STDOUT:   call void @_CEcho.Main(), !dbg !10
 // CHECK:STDOUT:   ret void, !dbg !11
diff --git a/toolchain/lower/testdata/function/call/implicit_empty_tuple_as_arg.carbon b/toolchain/lower/testdata/function/call/implicit_empty_tuple_as_arg.carbon
index 128cc0cd7b83..594a2e1f912d 100644
--- a/toolchain/lower/testdata/function/call/implicit_empty_tuple_as_arg.carbon
+++ b/toolchain/lower/testdata/function/call/implicit_empty_tuple_as_arg.carbon
@@ -37,8 +37,8 @@ fn Main() {
 // CHECK:STDOUT: ; Function Attrs: nounwind
 // CHECK:STDOUT: define void @_CMain.Main() #0 !dbg !10 {
 // CHECK:STDOUT: entry:
-// CHECK:STDOUT:   %_.var = alloca {}, align 8, !dbg !11
-// CHECK:STDOUT:   %.loc19_23.1.temp = alloca {}, align 8, !dbg !12
+// CHECK:STDOUT:   %_.var = alloca {}, align 1, !dbg !11
+// CHECK:STDOUT:   %.loc19_23.1.temp = alloca {}, align 1, !dbg !12
 // CHECK:STDOUT:   call void @llvm.lifetime.start.p0(ptr %_.var), !dbg !11
 // CHECK:STDOUT:   call void @_CFoo.Main(), !dbg !12
 // CHECK:STDOUT:   call void @llvm.lifetime.start.p0(ptr %.loc19_23.1.temp), !dbg !12
diff --git a/toolchain/lower/testdata/function/call/return_implicit.carbon b/toolchain/lower/testdata/function/call/return_implicit.carbon
index aa182b06c2d0..e811c169b657 100644
--- a/toolchain/lower/testdata/function/call/return_implicit.carbon
+++ b/toolchain/lower/testdata/function/call/return_implicit.carbon
@@ -30,7 +30,7 @@ fn Main() {
 // CHECK:STDOUT: ; Function Attrs: nounwind
 // CHECK:STDOUT: define void @_CMain.Main() #0 !dbg !8 {
 // CHECK:STDOUT: entry:
-// CHECK:STDOUT:   %_.var = alloca {}, align 8, !dbg !9
+// CHECK:STDOUT:   %_.var = alloca {}, align 1, !dbg !9
 // CHECK:STDOUT:   call void @llvm.lifetime.start.p0(ptr %_.var), !dbg !9
 // CHECK:STDOUT:   call void @_CMakeImplicitEmptyTuple.Main(), !dbg !10
 // CHECK:STDOUT:   ret void, !dbg !11
diff --git a/toolchain/lower/testdata/function/call/tuple_param_with_return_slot.carbon b/toolchain/lower/testdata/function/call/tuple_param_with_return_slot.carbon
index c4acddeab49a..b588bde03fd8 100644
--- a/toolchain/lower/testdata/function/call/tuple_param_with_return_slot.carbon
+++ b/toolchain/lower/testdata/function/call/tuple_param_with_return_slot.carbon
@@ -43,7 +43,7 @@ fn Main() {
 // CHECK:STDOUT: ; Function Attrs: nounwind
 // CHECK:STDOUT: define void @_CMain.Main() #0 !dbg !16 {
 // CHECK:STDOUT: entry:
-// CHECK:STDOUT:   %.loc18_21.1.temp = alloca { i32, i32, i32 }, align 8, !dbg !19
+// CHECK:STDOUT:   %.loc18_21.1.temp = alloca { i32, i32, i32 }, align 4, !dbg !19
 // CHECK:STDOUT:   call void @llvm.lifetime.start.p0(ptr %.loc18_21.1.temp), !dbg !19
 // CHECK:STDOUT:   call void @_CF.Main(ptr %.loc18_21.1.temp, { i32 } { i32 1 }, ptr @tuple.c4c.loc18_20.6), !dbg !19
 // CHECK:STDOUT:   call void @"_COp.9eed32d146d768a4:core.Destroy.Core"(ptr %.loc18_21.1.temp), !dbg !19
diff --git a/toolchain/lower/testdata/function/definition/destroy.carbon b/toolchain/lower/testdata/function/definition/destroy.carbon
index 8e0eeccd986e..037626a5bc70 100644
--- a/toolchain/lower/testdata/function/definition/destroy.carbon
+++ b/toolchain/lower/testdata/function/definition/destroy.carbon
@@ -89,7 +89,7 @@ fn InitLet() {
 // CHECK:STDOUT: ; Function Attrs: nounwind
 // CHECK:STDOUT: define void @_CCallF.Main() #0 !dbg !11 {
 // CHECK:STDOUT: entry:
-// CHECK:STDOUT:   %.loc12_6.2.temp = alloca {}, align 8, !dbg !14
+// CHECK:STDOUT:   %.loc12_6.2.temp = alloca {}, align 1, !dbg !14
 // CHECK:STDOUT:   call void @llvm.lifetime.start.p0(ptr %.loc12_6.2.temp), !dbg !14
 // CHECK:STDOUT:   call void @_CF.Main(ptr @C.val.loc12_6.6), !dbg !15
 // CHECK:STDOUT:   call void @_CG.Main(), !dbg !16
@@ -150,7 +150,7 @@ fn InitLet() {
 // CHECK:STDOUT: ; Function Attrs: nounwind
 // CHECK:STDOUT: define void @_CCallF.Main() #0 !dbg !11 {
 // CHECK:STDOUT: entry:
-// CHECK:STDOUT:   %_.var = alloca {}, align 8, !dbg !14
+// CHECK:STDOUT:   %_.var = alloca {}, align 1, !dbg !14
 // CHECK:STDOUT:   call void @llvm.lifetime.start.p0(ptr %_.var), !dbg !14
 // CHECK:STDOUT:   call void @llvm.memcpy.p0.p0.i64(ptr align 1 %_.var, ptr align 1 @C.val.loc6, i64 0, i1 false), !dbg !14
 // CHECK:STDOUT:   call void @_CF.Main(ptr %_.var), !dbg !15
@@ -223,7 +223,7 @@ fn InitLet() {
 // CHECK:STDOUT: ; Function Attrs: nounwind
 // CHECK:STDOUT: define void @_CInitVar.Main() #0 !dbg !12 {
 // CHECK:STDOUT: entry:
-// CHECK:STDOUT:   %_.var = alloca {}, align 8, !dbg !15
+// CHECK:STDOUT:   %_.var = alloca {}, align 1, !dbg !15
 // CHECK:STDOUT:   call void @llvm.lifetime.start.p0(ptr %_.var), !dbg !15
 // CHECK:STDOUT:   call void @_CF.Main(ptr %_.var), !dbg !16
 // CHECK:STDOUT:   call void @_CG.Main(), !dbg !17
@@ -240,7 +240,7 @@ fn InitLet() {
 // CHECK:STDOUT: ; Function Attrs: nounwind
 // CHECK:STDOUT: define void @_CInitLet.Main() #0 !dbg !25 {
 // CHECK:STDOUT: entry:
-// CHECK:STDOUT:   %.loc22_16.1.temp = alloca {}, align 8, !dbg !26
+// CHECK:STDOUT:   %.loc22_16.1.temp = alloca {}, align 1, !dbg !26
 // CHECK:STDOUT:   call void @llvm.lifetime.start.p0(ptr %.loc22_16.1.temp), !dbg !26
 // CHECK:STDOUT:   call void @_CF.Main(ptr %.loc22_16.1.temp), !dbg !26
 // CHECK:STDOUT:   call void @_CG.Main(), !dbg !27
diff --git a/toolchain/lower/testdata/function/definition/var_param.carbon b/toolchain/lower/testdata/function/definition/var_param.carbon
index 4c432e95155c..77b8ec5f0611 100644
--- a/toolchain/lower/testdata/function/definition/var_param.carbon
+++ b/toolchain/lower/testdata/function/definition/var_param.carbon
@@ -68,12 +68,12 @@ fn Call() {
 // CHECK:STDOUT: define void @_CCall.Main() #0 !dbg !35 {
 // CHECK:STDOUT: entry:
 // CHECK:STDOUT:   %_.var.loc15 = alloca i32, align 4, !dbg !38
-// CHECK:STDOUT:   %_.var.loc16 = alloca {}, align 8, !dbg !39
+// CHECK:STDOUT:   %_.var.loc16 = alloca {}, align 1, !dbg !39
 // CHECK:STDOUT:   %_.var.loc18_12 = alloca i32, align 4, !dbg !40
-// CHECK:STDOUT:   %_.var.loc18_24 = alloca {}, align 8, !dbg !41
+// CHECK:STDOUT:   %_.var.loc18_24 = alloca {}, align 1, !dbg !41
 // CHECK:STDOUT:   %_.var.loc20 = alloca i32, align 4, !dbg !42
-// CHECK:STDOUT:   %.loc27_18.2.temp = alloca {}, align 8, !dbg !43
-// CHECK:STDOUT:   %_.var.loc21 = alloca {}, align 8, !dbg !44
+// CHECK:STDOUT:   %.loc27_18.2.temp = alloca {}, align 1, !dbg !43
+// CHECK:STDOUT:   %_.var.loc21 = alloca {}, align 1, !dbg !44
 // CHECK:STDOUT:   call void @llvm.lifetime.start.p0(ptr %_.var.loc15), !dbg !38
 // CHECK:STDOUT:   store i32 1, ptr %_.var.loc15, align 4, !dbg !38
 // CHECK:STDOUT:   call void @_COneVar_i32.Main(ptr %_.var.loc15), !dbg !45
diff --git a/toolchain/lower/testdata/function/generic/call.carbon b/toolchain/lower/testdata/function/generic/call.carbon
index f04f418ae44c..1bc1f0980f0d 100644
--- a/toolchain/lower/testdata/function/generic/call.carbon
+++ b/toolchain/lower/testdata/function/generic/call.carbon
@@ -40,8 +40,8 @@ fn G() {
 // CHECK:STDOUT: ; Function Attrs: nounwind
 // CHECK:STDOUT: define void @_CG.Main() #0 !dbg !4 {
 // CHECK:STDOUT: entry:
-// CHECK:STDOUT:   %c.var = alloca {}, align 8, !dbg !7
-// CHECK:STDOUT:   %d.var = alloca {}, align 8, !dbg !8
+// CHECK:STDOUT:   %c.var = alloca {}, align 1, !dbg !7
+// CHECK:STDOUT:   %d.var = alloca {}, align 1, !dbg !8
 // CHECK:STDOUT:   %n.var = alloca i32, align 4, !dbg !9
 // CHECK:STDOUT:   %m.var = alloca double, align 8, !dbg !10
 // CHECK:STDOUT:   call void @llvm.lifetime.start.p0(ptr %c.var), !dbg !7
diff --git a/toolchain/lower/testdata/function/generic/call_basic.carbon b/toolchain/lower/testdata/function/generic/call_basic.carbon
index d94061943faa..1ad15e3437f8 100644
--- a/toolchain/lower/testdata/function/generic/call_basic.carbon
+++ b/toolchain/lower/testdata/function/generic/call_basic.carbon
@@ -131,8 +131,8 @@ fn M() {
 // CHECK:STDOUT:   %ptr_i32.var = alloca ptr, align 8, !dbg !55
 // CHECK:STDOUT:   %ptr_f64.var = alloca ptr, align 8, !dbg !56
 // CHECK:STDOUT:   %ptr_i8.var = alloca ptr, align 8, !dbg !57
-// CHECK:STDOUT:   %c.var = alloca {}, align 8, !dbg !58
-// CHECK:STDOUT:   %.loc43_6.2.temp = alloca {}, align 8, !dbg !59
+// CHECK:STDOUT:   %c.var = alloca {}, align 1, !dbg !58
+// CHECK:STDOUT:   %.loc43_6.2.temp = alloca {}, align 1, !dbg !59
 // CHECK:STDOUT:   call void @llvm.lifetime.start.p0(ptr %.loc29_6.2.temp), !dbg !51
 // CHECK:STDOUT:   %H.call.loc29 = call i32 @_CH.Main.980bd46fd9fb5b99(i32 %x), !dbg !51
 // CHECK:STDOUT:   store i32 %H.call.loc29, ptr %.loc29_6.2.temp, align 4, !dbg !51
@@ -188,8 +188,8 @@ fn M() {
 // CHECK:STDOUT:   %ptr_i32.var = alloca ptr, align 8, !dbg !81
 // CHECK:STDOUT:   %ptr_f64.var = alloca ptr, align 8, !dbg !82
 // CHECK:STDOUT:   %ptr_i8.var = alloca ptr, align 8, !dbg !83
-// CHECK:STDOUT:   %c.var = alloca {}, align 8, !dbg !84
-// CHECK:STDOUT:   %.loc43_6.2.temp = alloca {}, align 8, !dbg !85
+// CHECK:STDOUT:   %c.var = alloca {}, align 1, !dbg !84
+// CHECK:STDOUT:   %.loc43_6.2.temp = alloca {}, align 1, !dbg !85
 // CHECK:STDOUT:   call void @llvm.lifetime.start.p0(ptr %.loc29_6.2.temp), !dbg !77
 // CHECK:STDOUT:   %H.call.loc29 = call double @_CH.Main.3eb991d272a034fb(double %x), !dbg !77
 // CHECK:STDOUT:   store double %H.call.loc29, ptr %.loc29_6.2.temp, align 8, !dbg !77
diff --git a/toolchain/lower/testdata/function/generic/call_method.carbon b/toolchain/lower/testdata/function/generic/call_method.carbon
index 5c6a04c67cb7..e7226ec9369b 100644
--- a/toolchain/lower/testdata/function/generic/call_method.carbon
+++ b/toolchain/lower/testdata/function/generic/call_method.carbon
@@ -30,7 +30,7 @@ fn CallF() -> i32 {
 // CHECK:STDOUT: ; Function Attrs: nounwind
 // CHECK:STDOUT: define i32 @_CCallF.Main() #0 !dbg !4 {
 // CHECK:STDOUT: entry:
-// CHECK:STDOUT:   %c.var = alloca {}, align 8, !dbg !8
+// CHECK:STDOUT:   %c.var = alloca {}, align 1, !dbg !8
 // CHECK:STDOUT:   %n.var = alloca i32, align 4, !dbg !9
 // CHECK:STDOUT:   call void @llvm.lifetime.start.p0(ptr %c.var), !dbg !8
 // CHECK:STDOUT:   call void @llvm.memcpy.p0.p0.i64(ptr align 1 %c.var, ptr align 1 @C.val.loc20_3, i64 0, i1 false), !dbg !8
diff --git a/toolchain/lower/testdata/function/generic/call_recursive_basic.carbon b/toolchain/lower/testdata/function/generic/call_recursive_basic.carbon
index 6aa4d760561a..7038d0a7365a 100644
--- a/toolchain/lower/testdata/function/generic/call_recursive_basic.carbon
+++ b/toolchain/lower/testdata/function/generic/call_recursive_basic.carbon
@@ -59,8 +59,8 @@ fn M() {
 // CHECK:STDOUT:   %m.var = alloca double, align 8, !dbg !15
 // CHECK:STDOUT:   %ptr_i32.var = alloca ptr, align 8, !dbg !16
 // CHECK:STDOUT:   %ptr_f64.var = alloca ptr, align 8, !dbg !17
-// CHECK:STDOUT:   %c.var = alloca {}, align 8, !dbg !18
-// CHECK:STDOUT:   %.loc40_9.2.temp = alloca {}, align 8, !dbg !19
+// CHECK:STDOUT:   %c.var = alloca {}, align 1, !dbg !18
+// CHECK:STDOUT:   %.loc40_9.2.temp = alloca {}, align 1, !dbg !19
 // CHECK:STDOUT:   call void @llvm.lifetime.start.p0(ptr %n.var), !dbg !14
 // CHECK:STDOUT:   store i32 0, ptr %n.var, align 4, !dbg !14
 // CHECK:STDOUT:   call void @llvm.lifetime.start.p0(ptr %m.var), !dbg !15
diff --git a/toolchain/lower/testdata/function/generic/call_recursive_reorder_more.carbon b/toolchain/lower/testdata/function/generic/call_recursive_reorder_more.carbon
index e78ccddeab92..b5ee9cce0e9b 100644
--- a/toolchain/lower/testdata/function/generic/call_recursive_reorder_more.carbon
+++ b/toolchain/lower/testdata/function/generic/call_recursive_reorder_more.carbon
@@ -72,7 +72,7 @@ fn M() {
 // CHECK:STDOUT:   call void @llvm.lifetime.start.p0(ptr %val_i32.var), !dbg !8
 // CHECK:STDOUT:   store i32 poison, ptr %val_i32.var, align 4, !dbg !8
 // CHECK:STDOUT:   call void @llvm.lifetime.start.p0(ptr %val_i64.var), !dbg !9
-// CHECK:STDOUT:   store i64 poison, ptr %val_i64.var, align 4, !dbg !9
+// CHECK:STDOUT:   store i64 poison, ptr %val_i64.var, align 8, !dbg !9
 // CHECK:STDOUT:   call void @llvm.lifetime.start.p0(ptr %val_f64.var), !dbg !10
 // CHECK:STDOUT:   store double poison, ptr %val_f64.var, align 8, !dbg !10
 // CHECK:STDOUT:   call void @llvm.lifetime.start.p0(ptr %val_bool.var), !dbg !11
@@ -98,7 +98,7 @@ fn M() {
 // CHECK:STDOUT:   %.loc40_15 = load ptr, ptr %ptr_bool.var, align 8, !dbg !25
 // CHECK:STDOUT:   %.loc40_25 = load ptr, ptr %ptr_i16.var, align 8, !dbg !26
 // CHECK:STDOUT:   %F.call.loc40 = call i32 @_CF.Main.e1d834dc162d21b2(i1 %.loc40_51, ptr %.loc40_15, ptr %.loc40_25, i32 0), !dbg !27
-// CHECK:STDOUT:   %.loc41_5 = load i64, ptr %val_i64.var, align 4, !dbg !28
+// CHECK:STDOUT:   %.loc41_5 = load i64, ptr %val_i64.var, align 8, !dbg !28
 // CHECK:STDOUT:   %.loc41_14 = load i8, ptr %val_bool.var, align 1, !dbg !29
 // CHECK:STDOUT:   %.loc41_142 = trunc i8 %.loc41_14 to i1, !dbg !29
 // CHECK:STDOUT:   %.loc41_24 = load ptr, ptr %ptr_bool.var, align 8, !dbg !30
diff --git a/toolchain/lower/testdata/function/generic/call_specific_in_class.carbon b/toolchain/lower/testdata/function/generic/call_specific_in_class.carbon
index 77493abc2cf3..0a8272e2622a 100644
--- a/toolchain/lower/testdata/function/generic/call_specific_in_class.carbon
+++ b/toolchain/lower/testdata/function/generic/call_specific_in_class.carbon
@@ -63,7 +63,7 @@ fn M() {
 // CHECK:STDOUT:   %ptr_i8.var = alloca ptr, align 8, !dbg !16
 // CHECK:STDOUT:   %var_i32.var = alloca i32, align 4, !dbg !17
 // CHECK:STDOUT:   %var_f64.var = alloca double, align 8, !dbg !18
-// CHECK:STDOUT:   %_.var = alloca {}, align 8, !dbg !19
+// CHECK:STDOUT:   %_.var = alloca {}, align 1, !dbg !19
 // CHECK:STDOUT:   call void @llvm.lifetime.start.p0(ptr %ptr_i32.var), !dbg !14
 // CHECK:STDOUT:   store ptr poison, ptr %ptr_i32.var, align 8, !dbg !14
 // CHECK:STDOUT:   %.loc34_5 = load ptr, ptr %ptr_i32.var, align 8, !dbg !20
@@ -138,7 +138,7 @@ fn M() {
 // CHECK:STDOUT: ; Function Attrs: nounwind
 // CHECK:STDOUT: define linkonce_odr ptr @_CG.Main.3890ad819211e245(ptr %x) #0 !dbg !67 {
 // CHECK:STDOUT: entry:
-// CHECK:STDOUT:   %c.var = alloca {}, align 8, !dbg !70
+// CHECK:STDOUT:   %c.var = alloca {}, align 1, !dbg !70
 // CHECK:STDOUT:   call void @llvm.lifetime.start.p0(ptr %c.var), !dbg !70
 // CHECK:STDOUT:   %C.Cfn.call = call ptr @_CCfn.C.Main.3890ad819211e245(ptr %c.var, ptr %x), !dbg !71
 // CHECK:STDOUT:   call void @"_COp.b8b1f433ad216ca6:core.Destroy.Core"(ptr %c.var), !dbg !70
@@ -148,7 +148,7 @@ fn M() {
 // CHECK:STDOUT: ; Function Attrs: nounwind
 // CHECK:STDOUT: define linkonce_odr i32 @_CG.Main.980bd46fd9fb5b99(i32 %x) #0 !dbg !73 {
 // CHECK:STDOUT: entry:
-// CHECK:STDOUT:   %c.var = alloca {}, align 8, !dbg !76
+// CHECK:STDOUT:   %c.var = alloca {}, align 1, !dbg !76
 // CHECK:STDOUT:   call void @llvm.lifetime.start.p0(ptr %c.var), !dbg !76
 // CHECK:STDOUT:   %C.Cfn.call = call i32 @_CCfn.C.Main.980bd46fd9fb5b99(ptr %c.var, i32 %x), !dbg !77
 // CHECK:STDOUT:   call void @"_COp.b8b1f433ad216ca6:core.Destroy.Core"(ptr %c.var), !dbg !76
@@ -158,7 +158,7 @@ fn M() {
 // CHECK:STDOUT: ; Function Attrs: nounwind
 // CHECK:STDOUT: define linkonce_odr double @_CG.Main.3eb991d272a034fb(double %x) #0 !dbg !79 {
 // CHECK:STDOUT: entry:
-// CHECK:STDOUT:   %c.var = alloca {}, align 8, !dbg !82
+// CHECK:STDOUT:   %c.var = alloca {}, align 1, !dbg !82
 // CHECK:STDOUT:   call void @llvm.lifetime.start.p0(ptr %c.var), !dbg !82
 // CHECK:STDOUT:   %C.Cfn.call = call double @_CCfn.C.Main.3eb991d272a034fb(ptr %c.var, double %x), !dbg !83
 // CHECK:STDOUT:   call void @"_COp.b8b1f433ad216ca6:core.Destroy.Core"(ptr %c.var), !dbg !82
@@ -168,7 +168,7 @@ fn M() {
 // CHECK:STDOUT: ; Function Attrs: nounwind
 // CHECK:STDOUT: define linkonce_odr %type @_CG.Main.22a6f624d7af1d76(%type %x) #0 !dbg !85 {
 // CHECK:STDOUT: entry:
-// CHECK:STDOUT:   %c.var = alloca {}, align 8, !dbg !88
+// CHECK:STDOUT:   %c.var = alloca {}, align 1, !dbg !88
 // CHECK:STDOUT:   call void @llvm.lifetime.start.p0(ptr %c.var), !dbg !88
 // CHECK:STDOUT:   %C.Cfn.call = call %type @_CCfn.C.Main.22a6f624d7af1d76(ptr %c.var, %type %x), !dbg !89
 // CHECK:STDOUT:   call void @"_COp.b8b1f433ad216ca6:core.Destroy.Core"(ptr %c.var), !dbg !88
diff --git a/toolchain/lower/testdata/function/generic/type_representation.carbon b/toolchain/lower/testdata/function/generic/type_representation.carbon
index ef1cd605c4c3..6649513ab364 100644
--- a/toolchain/lower/testdata/function/generic/type_representation.carbon
+++ b/toolchain/lower/testdata/function/generic/type_representation.carbon
@@ -211,7 +211,7 @@ fn F_nested_tuple(a: ((i32, i32), X)) -> ((i32, i32), X) {
 // CHECK:STDOUT: ; Function Attrs: nounwind
 // CHECK:STDOUT: define linkonce_odr void @_CF.Main.e4214cdf04e44ea0(ptr sret({ i32, i32 }) %return, ptr %a) #0 !dbg !91 {
 // CHECK:STDOUT: entry:
-// CHECK:STDOUT:   %_.var = alloca { i32, i32 }, align 8, !dbg !94
+// CHECK:STDOUT:   %_.var = alloca { i32, i32 }, align 4, !dbg !94
 // CHECK:STDOUT:   call void @llvm.lifetime.start.p0(ptr %_.var), !dbg !94
 // CHECK:STDOUT:   call void @"_COp.X.Main:Copy.Main"(ptr %_.var, ptr %a), !dbg !95
 // CHECK:STDOUT:   call void @"_COp.X.Main:Copy.Main"(ptr %return, ptr %a), !dbg !96
@@ -222,7 +222,7 @@ fn F_nested_tuple(a: ((i32, i32), X)) -> ((i32, i32), X) {
 // CHECK:STDOUT: ; Function Attrs: nounwind
 // CHECK:STDOUT: define linkonce_odr void @_CF.Main.6942691454f579cd() #0 !dbg !98 {
 // CHECK:STDOUT: entry:
-// CHECK:STDOUT:   %_.var = alloca {}, align 8, !dbg !99
+// CHECK:STDOUT:   %_.var = alloca {}, align 1, !dbg !99
 // CHECK:STDOUT:   call void @llvm.lifetime.start.p0(ptr %_.var), !dbg !99
 // CHECK:STDOUT:   call void @"_COp.61ea2aba74ab3bf1:Copy.Main"(), !dbg !100
 // CHECK:STDOUT:   call void @"_COp.61ea2aba74ab3bf1:Copy.Main"(), !dbg !101
@@ -232,7 +232,7 @@ fn F_nested_tuple(a: ((i32, i32), X)) -> ((i32, i32), X) {
 // CHECK:STDOUT: ; Function Attrs: nounwind
 // CHECK:STDOUT: define linkonce_odr void @_CF.Main.52eb52f0ffbd1db6(ptr sret({ i32, i32 }) %return, ptr %a) #0 !dbg !103 {
 // CHECK:STDOUT: entry:
-// CHECK:STDOUT:   %_.var = alloca { i32, i32 }, align 8, !dbg !106
+// CHECK:STDOUT:   %_.var = alloca { i32, i32 }, align 4, !dbg !106
 // CHECK:STDOUT:   call void @llvm.lifetime.start.p0(ptr %_.var), !dbg !106
 // CHECK:STDOUT:   call void @"_COp.87cc08e781602b22:Copy.Main"(ptr %_.var, ptr %a), !dbg !107
 // CHECK:STDOUT:   call void @"_COp.87cc08e781602b22:Copy.Main"(ptr %return, ptr %a), !dbg !108
@@ -243,7 +243,7 @@ fn F_nested_tuple(a: ((i32, i32), X)) -> ((i32, i32), X) {
 // CHECK:STDOUT: ; Function Attrs: nounwind
 // CHECK:STDOUT: define linkonce_odr void @_CF.Main.cbd425227ee9ed4b(ptr sret({ { i32, i32 }, { i32, i32 } }) %return, ptr %a) #0 !dbg !110 {
 // CHECK:STDOUT: entry:
-// CHECK:STDOUT:   %_.var = alloca { { i32, i32 }, { i32, i32 } }, align 8, !dbg !113
+// CHECK:STDOUT:   %_.var = alloca { { i32, i32 }, { i32, i32 } }, align 4, !dbg !113
 // CHECK:STDOUT:   call void @llvm.lifetime.start.p0(ptr %_.var), !dbg !113
 // CHECK:STDOUT:   call void @"_COp.b1957bb3c5dab115:Copy.Main"(ptr %_.var, ptr %a), !dbg !114
 // CHECK:STDOUT:   call void @"_COp.b1957bb3c5dab115:Copy.Main"(ptr %return, ptr %a), !dbg !115
diff --git a/toolchain/lower/testdata/impl/impl.carbon b/toolchain/lower/testdata/impl/impl.carbon
index d8ba5f8469a2..d4eb1ae4d28f 100644
--- a/toolchain/lower/testdata/impl/impl.carbon
+++ b/toolchain/lower/testdata/impl/impl.carbon
@@ -147,8 +147,8 @@ impl C(B) as I {
 // CHECK:STDOUT: ; Function Attrs: nounwind
 // CHECK:STDOUT: define void @_CF1.Main(ptr %x, ptr %y) #0 !dbg !15 {
 // CHECK:STDOUT: entry:
-// CHECK:STDOUT:   %a.var = alloca {}, align 8, !dbg !21
-// CHECK:STDOUT:   %b.var = alloca {}, align 8, !dbg !22
+// CHECK:STDOUT:   %a.var = alloca {}, align 1, !dbg !21
+// CHECK:STDOUT:   %b.var = alloca {}, align 1, !dbg !22
 // CHECK:STDOUT:   call void @llvm.lifetime.start.p0(ptr %a.var), !dbg !21
 // CHECK:STDOUT:   call void @"_CF.C.Main:I.837256a62795a301.Main"(ptr %a.var, ptr %x), !dbg !23
 // CHECK:STDOUT:   call void @llvm.lifetime.start.p0(ptr %b.var), !dbg !22
diff --git a/toolchain/lower/testdata/impl/import_facet.carbon b/toolchain/lower/testdata/impl/import_facet.carbon
index 0445ac21f29d..ce05a6c23e51 100644
--- a/toolchain/lower/testdata/impl/import_facet.carbon
+++ b/toolchain/lower/testdata/impl/import_facet.carbon
@@ -90,7 +90,7 @@ fn F(d: D(i32)) -> i32* {
 // CHECK:STDOUT: ; Function Attrs: nounwind
 // CHECK:STDOUT: define ptr @_CF.Main(ptr %d) #0 !dbg !4 {
 // CHECK:STDOUT: entry:
-// CHECK:STDOUT:   %.loc5_21.1.temp = alloca {}, align 8, !dbg !10
+// CHECK:STDOUT:   %.loc5_21.1.temp = alloca {}, align 1, !dbg !10
 // CHECK:STDOUT:   call void @llvm.lifetime.start.p0(ptr %.loc5_21.1.temp), !dbg !10
 // CHECK:STDOUT:   call void @"_CGetI.D.eb057aa32837c84e.Main:I.Main.c8fd090a2e741f70"(ptr %.loc5_21.1.temp, ptr %d), !dbg !10
 // CHECK:STDOUT:   %C.GetC.call = call ptr @_CGetC.C.Main.305e140e9c2d2c5b(ptr %.loc5_21.1.temp), !dbg !10
diff --git a/toolchain/lower/testdata/impl/import_thunk.carbon b/toolchain/lower/testdata/impl/import_thunk.carbon
index 02f78ccea689..90aea36d62bb 100644
--- a/toolchain/lower/testdata/impl/import_thunk.carbon
+++ b/toolchain/lower/testdata/impl/import_thunk.carbon
@@ -102,8 +102,8 @@ fn Test(a: A) -> C {
 // CHECK:STDOUT: ; Function Attrs: alwaysinline nounwind
 // CHECK:STDOUT: define void @"_CF:thunk:I.01f5c37cad34e90b.Main:61ea2aba74ab3bf1:I.Main"(ptr sret({ i32 }) %return, ptr %a) #1 !dbg !25 {
 // CHECK:STDOUT: entry:
-// CHECK:STDOUT:   %.loc20_19.1.temp = alloca { i32 }, align 8, !dbg !28
-// CHECK:STDOUT:   %.loc16_9.1.temp = alloca { i32 }, align 8, !dbg !29
+// CHECK:STDOUT:   %.loc20_19.1.temp = alloca { i32 }, align 4, !dbg !28
+// CHECK:STDOUT:   %.loc16_9.1.temp = alloca { i32 }, align 4, !dbg !29
 // CHECK:STDOUT:   call void @llvm.lifetime.start.p0(ptr %.loc20_19.1.temp), !dbg !28
 // CHECK:STDOUT:   call void @llvm.lifetime.start.p0(ptr %.loc16_9.1.temp), !dbg !29
 // CHECK:STDOUT:   call void @"_CConvert.A.Main:ImplicitAs.8b79c6c1932e58f6.Core"(ptr %.loc16_9.1.temp, ptr %a), !dbg !29
@@ -199,9 +199,9 @@ fn Test(a: A) -> C {
 // CHECK:STDOUT: ; Function Attrs: nounwind
 // CHECK:STDOUT: define void @_CTest.Main(ptr sret({ i32 }) %return, ptr %a) #0 !dbg !4 {
 // CHECK:STDOUT: entry:
-// CHECK:STDOUT:   %.loc7_20.1.temp = alloca { i32 }, align 8, !dbg !10
-// CHECK:STDOUT:   %.loc7_20.2.temp = alloca { i32 }, align 8, !dbg !10
-// CHECK:STDOUT:   %.loc7_19.1.temp = alloca { i32 }, align 8, !dbg !11
+// CHECK:STDOUT:   %.loc7_20.1.temp = alloca { i32 }, align 4, !dbg !10
+// CHECK:STDOUT:   %.loc7_20.2.temp = alloca { i32 }, align 4, !dbg !10
+// CHECK:STDOUT:   %.loc7_19.1.temp = alloca { i32 }, align 4, !dbg !11
 // CHECK:STDOUT:   call void @llvm.lifetime.start.p0(ptr %.loc7_20.1.temp), !dbg !10
 // CHECK:STDOUT:   call void @llvm.lifetime.start.p0(ptr %.loc7_20.2.temp), !dbg !10
 // CHECK:STDOUT:   call void @llvm.lifetime.start.p0(ptr %.loc7_19.1.temp), !dbg !11
@@ -298,8 +298,8 @@ fn Test(a: A) -> C {
 // CHECK:STDOUT: ; Function Attrs: alwaysinline nounwind
 // CHECK:STDOUT: define void @"_CF:thunk:I.5df87795ec73cda9.Main:X.Main:I.Main"(ptr sret({ i32 }) %return, ptr %a) #1 !dbg !13 {
 // CHECK:STDOUT: entry:
-// CHECK:STDOUT:   %.loc9_19.1.temp = alloca { i32 }, align 8, !dbg !16
-// CHECK:STDOUT:   %.2.temp = alloca { i32 }, align 8
+// CHECK:STDOUT:   %.loc9_19.1.temp = alloca { i32 }, align 4, !dbg !16
+// CHECK:STDOUT:   %.2.temp = alloca { i32 }, align 4
 // CHECK:STDOUT:   call void @llvm.lifetime.start.p0(ptr %.loc9_19.1.temp), !dbg !16
 // CHECK:STDOUT:   call void @llvm.lifetime.start.p0(ptr %.2.temp)
 // CHECK:STDOUT:   call void @"_CConvert.A.Main:ImplicitAs.0b3b8a3403fe0e1d.Core"(ptr %.2.temp, ptr %a), !dbg !17
@@ -387,9 +387,9 @@ fn Test(a: A) -> C {
 // CHECK:STDOUT: ; Function Attrs: nounwind
 // CHECK:STDOUT: define void @_CTest.Main(ptr sret({ i32 }) %return, ptr %a) #0 !dbg !4 {
 // CHECK:STDOUT: entry:
-// CHECK:STDOUT:   %.loc8_19.1.temp = alloca { i32 }, align 8, !dbg !10
-// CHECK:STDOUT:   %.loc8_19.2.temp = alloca { i32 }, align 8, !dbg !10
-// CHECK:STDOUT:   %.loc8_18.1.temp = alloca { i32 }, align 8, !dbg !11
+// CHECK:STDOUT:   %.loc8_19.1.temp = alloca { i32 }, align 4, !dbg !10
+// CHECK:STDOUT:   %.loc8_19.2.temp = alloca { i32 }, align 4, !dbg !10
+// CHECK:STDOUT:   %.loc8_18.1.temp = alloca { i32 }, align 4, !dbg !11
 // CHECK:STDOUT:   call void @llvm.lifetime.start.p0(ptr %.loc8_19.1.temp), !dbg !10
 // CHECK:STDOUT:   call void @llvm.lifetime.start.p0(ptr %.loc8_19.2.temp), !dbg !10
 // CHECK:STDOUT:   call void @llvm.lifetime.start.p0(ptr %.loc8_18.1.temp), !dbg !11
diff --git a/toolchain/lower/testdata/impl/thunk.carbon b/toolchain/lower/testdata/impl/thunk.carbon
index 7e6dc937e769..1ef48ac96b2d 100644
--- a/toolchain/lower/testdata/impl/thunk.carbon
+++ b/toolchain/lower/testdata/impl/thunk.carbon
@@ -106,8 +106,8 @@ fn CallCallGeneric(c: C(()), b: B) -> A {
 // CHECK:STDOUT: ; Function Attrs: alwaysinline nounwind
 // CHECK:STDOUT: define void @"_CF:thunk:I.01f5c37cad34e90b.Main:61ea2aba74ab3bf1:I.Main"(ptr sret({ i32 }) %return, ptr %a) #1 !dbg !25 {
 // CHECK:STDOUT: entry:
-// CHECK:STDOUT:   %.loc20_19.1.temp = alloca { i32 }, align 8, !dbg !28
-// CHECK:STDOUT:   %.loc16_9.1.temp = alloca { i32 }, align 8, !dbg !29
+// CHECK:STDOUT:   %.loc20_19.1.temp = alloca { i32 }, align 4, !dbg !28
+// CHECK:STDOUT:   %.loc16_9.1.temp = alloca { i32 }, align 4, !dbg !29
 // CHECK:STDOUT:   call void @llvm.lifetime.start.p0(ptr %.loc20_19.1.temp), !dbg !28
 // CHECK:STDOUT:   call void @llvm.lifetime.start.p0(ptr %.loc16_9.1.temp), !dbg !29
 // CHECK:STDOUT:   call void @"_CConvert.A.Main:ImplicitAs.8b79c6c1932e58f6.Core"(ptr %.loc16_9.1.temp, ptr %a), !dbg !29
@@ -139,9 +139,9 @@ fn CallCallGeneric(c: C(()), b: B) -> A {
 // CHECK:STDOUT: ; Function Attrs: nounwind
 // CHECK:STDOUT: define void @_CTest.Main(ptr sret({ i32 }) %return, ptr %a) #0 !dbg !47 {
 // CHECK:STDOUT: entry:
-// CHECK:STDOUT:   %.loc24_20.1.temp = alloca { i32 }, align 8, !dbg !50
-// CHECK:STDOUT:   %.loc24_20.2.temp = alloca { i32 }, align 8, !dbg !50
-// CHECK:STDOUT:   %.loc24_19.1.temp = alloca { i32 }, align 8, !dbg !51
+// CHECK:STDOUT:   %.loc24_20.1.temp = alloca { i32 }, align 4, !dbg !50
+// CHECK:STDOUT:   %.loc24_20.2.temp = alloca { i32 }, align 4, !dbg !50
+// CHECK:STDOUT:   %.loc24_19.1.temp = alloca { i32 }, align 4, !dbg !51
 // CHECK:STDOUT:   call void @llvm.lifetime.start.p0(ptr %.loc24_20.1.temp), !dbg !50
 // CHECK:STDOUT:   call void @llvm.lifetime.start.p0(ptr %.loc24_20.2.temp), !dbg !50
 // CHECK:STDOUT:   call void @llvm.lifetime.start.p0(ptr %.loc24_19.1.temp), !dbg !51
@@ -248,9 +248,9 @@ fn CallCallGeneric(c: C(()), b: B) -> A {
 // CHECK:STDOUT: ; Function Attrs: nounwind
 // CHECK:STDOUT: define void @_CCall.Main(ptr sret({}) %return, ptr %c, ptr %b) #0 !dbg !21 {
 // CHECK:STDOUT: entry:
-// CHECK:STDOUT:   %.loc22_23.1.temp = alloca {}, align 8, !dbg !27
-// CHECK:STDOUT:   %.loc22_23.3.temp = alloca {}, align 8, !dbg !27
-// CHECK:STDOUT:   %.loc22_22.1.temp = alloca {}, align 8, !dbg !28
+// CHECK:STDOUT:   %.loc22_23.1.temp = alloca {}, align 1, !dbg !27
+// CHECK:STDOUT:   %.loc22_23.3.temp = alloca {}, align 1, !dbg !27
+// CHECK:STDOUT:   %.loc22_22.1.temp = alloca {}, align 1, !dbg !28
 // CHECK:STDOUT:   call void @llvm.lifetime.start.p0(ptr %.loc22_23.1.temp), !dbg !27
 // CHECK:STDOUT:   call void @llvm.lifetime.start.p0(ptr %.loc22_23.3.temp), !dbg !27
 // CHECK:STDOUT:   call void @llvm.lifetime.start.p0(ptr %.loc22_22.1.temp), !dbg !28
@@ -292,8 +292,8 @@ fn CallCallGeneric(c: C(()), b: B) -> A {
 // CHECK:STDOUT: ; Function Attrs: alwaysinline nounwind
 // CHECK:STDOUT: define linkonce_odr void @"_CF:thunk:I.a61d280f5ea4bfd8.Main:C.eb057aa32837c84e.Main:I.eb057aa32837c84e.Main.e43630e9a6c38c3f"(ptr sret({}) %return, ptr %self, ptr %x) #2 !dbg !47 {
 // CHECK:STDOUT: entry:
-// CHECK:STDOUT:   %.loc18_38.2.temp = alloca {}, align 8, !dbg !51
-// CHECK:STDOUT:   %.loc12_21.1.temp = alloca {}, align 8, !dbg !52
+// CHECK:STDOUT:   %.loc18_38.2.temp = alloca {}, align 1, !dbg !51
+// CHECK:STDOUT:   %.loc12_21.1.temp = alloca {}, align 1, !dbg !52
 // CHECK:STDOUT:   call void @llvm.lifetime.start.p0(ptr %.loc18_38.2.temp), !dbg !51
 // CHECK:STDOUT:   call void @llvm.lifetime.start.p0(ptr %.loc12_21.1.temp), !dbg !52
 // CHECK:STDOUT:   call void @"_CConvert.B.Main:ImplicitAs.46f7e99dd8f31ccb.Core"(ptr %.loc12_21.1.temp, ptr %x), !dbg !52
diff --git a/toolchain/lower/testdata/index/array_element_access.carbon b/toolchain/lower/testdata/index/array_element_access.carbon
index 33a7ecfa8eb6..ce697098555f 100644
--- a/toolchain/lower/testdata/index/array_element_access.carbon
+++ b/toolchain/lower/testdata/index/array_element_access.carbon
@@ -48,7 +48,7 @@ fn Run() {
 // CHECK:STDOUT: define i32 @main() #0 !dbg !13 {
 // CHECK:STDOUT: entry:
 // CHECK:STDOUT:   %a.var = alloca [2 x i32], align 4, !dbg !17
-// CHECK:STDOUT:   %.loc17_28.1.temp = alloca { i32, i32 }, align 8, !dbg !18
+// CHECK:STDOUT:   %.loc17_28.1.temp = alloca { i32, i32 }, align 4, !dbg !18
 // CHECK:STDOUT:   %b.var = alloca i32, align 4, !dbg !19
 // CHECK:STDOUT:   %_.var.loc19 = alloca i32, align 4, !dbg !20
 // CHECK:STDOUT:   %_.var.loc20 = alloca i32, align 4, !dbg !21
diff --git a/toolchain/lower/testdata/interop/cpp/class/import/alignment.carbon b/toolchain/lower/testdata/interop/cpp/class/import/alignment.carbon
new file mode 100644
index 000000000000..74b0a337a1dc
--- /dev/null
+++ b/toolchain/lower/testdata/interop/cpp/class/import/alignment.carbon
@@ -0,0 +1,248 @@
+// Part of the Carbon Language project, under the Apache License v2.0 with LLVM
+// Exceptions. See /LICENSE for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+// INCLUDE-FILE: toolchain/testing/testdata/min_prelude/primitives.carbon
+//
+// AUTOUPDATE
+// TIP: To test this file alone, run:
+// TIP:   bazel test //toolchain/testing:file_test --test_arg=--file_tests=toolchain/lower/testdata/interop/cpp/class/import/alignment.carbon
+// TIP: To dump output, run:
+// TIP:   bazel run //toolchain/testing:file_test -- --dump_output --file_tests=toolchain/lower/testdata/interop/cpp/class/import/alignment.carbon
+
+// --- alignment.carbon
+
+library "[[@TEST_NAME]]";
+
+import Cpp;
+
+inline Cpp '''
+struct NaturallyAligned {
+  int n;
+};
+
+struct alignas(16) ExtraAlignment {
+  int n;
+};
+
+struct __attribute__((packed)) Packed {
+  int n;
+};
+
+template<typename T>
+void Take(T&);
+''';
+
+fn NaturallyAligned(n: i32) {
+  var a: Cpp.NaturallyAligned;
+  a.n = n;
+  Cpp.Take(ref a);
+}
+
+fn ExtraAlignment(n: i32) {
+  var a: Cpp.ExtraAlignment;
+  // TODO: We only specify a 4-byte alignment here, although we know that `a.n`
+  // has more alignment.
+  a.n = n;
+  Cpp.Take(ref a);
+}
+
+fn Packed(n: i32) {
+  var a: Cpp.Packed;
+  // TODO: We incorrectly specify a 4-byte alignment here. We may need to give
+  // underaligned fields a different type in order to prevent miscompiling code
+  // like this.
+  a.n = n;
+  Cpp.Take(ref a);
+}
+
+// CHECK:STDOUT: ; ModuleID = 'alignment.carbon'
+// CHECK:STDOUT: source_filename = "alignment.carbon"
+// CHECK:STDOUT: target datalayout = "e-m:e-p270:32:32-p271:32:32-p272:64:64-i64:64-i128:128-f80:128-n8:16:32:64-S128"
+// CHECK:STDOUT: target triple = "x86_64-unknown-linux-gnu"
+// CHECK:STDOUT:
+// CHECK:STDOUT: ; Function Attrs: nounwind
+// CHECK:STDOUT: define void @_CNaturallyAligned.Main(i32 %n) #0 !dbg !11 {
+// CHECK:STDOUT: entry:
+// CHECK:STDOUT:   %a.var = alloca [4 x i8], align 4, !dbg !17
+// CHECK:STDOUT:   call void @llvm.lifetime.start.p0(ptr %a.var), !dbg !17
+// CHECK:STDOUT:   call void @"_COp.cbe5dd53b28eb3d1:DefaultOrUnformed.Core.53704887462f6065"(ptr %a.var), !dbg !17
+// CHECK:STDOUT:   %.loc25.n = getelementptr inbounds nuw [4 x i8], ptr %a.var, i32 0, i32 0, !dbg !18
+// CHECK:STDOUT:   store i32 %n, ptr %.loc25.n, align 4, !dbg !18
+// CHECK:STDOUT:   call void @_Z4TakeI16NaturallyAlignedEvRT_(ptr %a.var), !dbg !19
+// CHECK:STDOUT:   ret void, !dbg !20
+// CHECK:STDOUT: }
+// CHECK:STDOUT:
+// CHECK:STDOUT: ; Function Attrs: alwaysinline mustprogress nounwind uwtable
+// CHECK:STDOUT: define internal void @_ZN16NaturallyAlignedC1Ev.carbon_thunk.(ptr noundef %return) #1 {
+// CHECK:STDOUT: entry:
+// CHECK:STDOUT:   %return.addr = alloca ptr, align 8
+// CHECK:STDOUT:   store ptr %return, ptr %return.addr, align 8, !tbaa !21
+// CHECK:STDOUT:   %0 = load ptr, ptr %return.addr, align 8, !tbaa !21
+// CHECK:STDOUT:   ret void
+// CHECK:STDOUT: }
+// CHECK:STDOUT:
+// CHECK:STDOUT: ; Function Attrs: alwaysinline nounwind
+// CHECK:STDOUT: define void @"_COp:thunk:Default.381601f5a2bd2e81.Core:NaturallyAligned.Cpp"(ptr sret([4 x i8]) %return) #2 !dbg !24 {
+// CHECK:STDOUT: entry:
+// CHECK:STDOUT:   call void @_ZN16NaturallyAlignedC1Ev.carbon_thunk.(ptr %return), !dbg !28
+// CHECK:STDOUT:   ret void, !dbg !28
+// CHECK:STDOUT: }
+// CHECK:STDOUT:
+// CHECK:STDOUT: declare void @_Z4TakeI16NaturallyAlignedEvRT_(ptr noundef nonnull align 4 dereferenceable(4)) #3
+// CHECK:STDOUT:
+// CHECK:STDOUT: ; Function Attrs: nounwind
+// CHECK:STDOUT: define void @_CExtraAlignment.Main(i32 %n) #0 !dbg !29 {
+// CHECK:STDOUT: entry:
+// CHECK:STDOUT:   %a.var = alloca [16 x i8], align 16, !dbg !32
+// CHECK:STDOUT:   call void @llvm.lifetime.start.p0(ptr %a.var), !dbg !32
+// CHECK:STDOUT:   call void @"_COp.cbe5dd53b28eb3d1:DefaultOrUnformed.Core.f529dae788690cbe"(ptr %a.var), !dbg !32
+// CHECK:STDOUT:   %.loc33.n = getelementptr inbounds nuw [16 x i8], ptr %a.var, i32 0, i32 0, !dbg !33
+// CHECK:STDOUT:   store i32 %n, ptr %.loc33.n, align 4, !dbg !33
+// CHECK:STDOUT:   call void @_Z4TakeI14ExtraAlignmentEvRT_(ptr %a.var), !dbg !34
+// CHECK:STDOUT:   ret void, !dbg !35
+// CHECK:STDOUT: }
+// CHECK:STDOUT:
+// CHECK:STDOUT: ; Function Attrs: alwaysinline mustprogress nounwind uwtable
+// CHECK:STDOUT: define internal void @_ZN14ExtraAlignmentC1Ev.carbon_thunk.(ptr noundef %return) #1 {
+// CHECK:STDOUT: entry:
+// CHECK:STDOUT:   %return.addr = alloca ptr, align 8
+// CHECK:STDOUT:   store ptr %return, ptr %return.addr, align 8, !tbaa !36
+// CHECK:STDOUT:   %0 = load ptr, ptr %return.addr, align 8, !tbaa !36
+// CHECK:STDOUT:   ret void
+// CHECK:STDOUT: }
+// CHECK:STDOUT:
+// CHECK:STDOUT: ; Function Attrs: alwaysinline nounwind
+// CHECK:STDOUT: define void @"_COp:thunk:Default.6ca50d719a15fa24.Core:ExtraAlignment.Cpp"(ptr sret([16 x i8]) %return) #2 !dbg !38 {
+// CHECK:STDOUT: entry:
+// CHECK:STDOUT:   call void @_ZN14ExtraAlignmentC1Ev.carbon_thunk.(ptr %return), !dbg !39
+// CHECK:STDOUT:   ret void, !dbg !39
+// CHECK:STDOUT: }
+// CHECK:STDOUT:
+// CHECK:STDOUT: declare void @_Z4TakeI14ExtraAlignmentEvRT_(ptr noundef nonnull align 16 dereferenceable(16)) #3
+// CHECK:STDOUT:
+// CHECK:STDOUT: ; Function Attrs: nounwind
+// CHECK:STDOUT: define void @_CPacked.Main(i32 %n) #0 !dbg !40 {
+// CHECK:STDOUT: entry:
+// CHECK:STDOUT:   %a.var = alloca [4 x i8], align 1, !dbg !43
+// CHECK:STDOUT:   call void @llvm.lifetime.start.p0(ptr %a.var), !dbg !43
+// CHECK:STDOUT:   call void @"_COp.cbe5dd53b28eb3d1:DefaultOrUnformed.Core.ee398c9a806dbb35"(ptr %a.var), !dbg !43
+// CHECK:STDOUT:   %.loc42.n = getelementptr inbounds nuw [4 x i8], ptr %a.var, i32 0, i32 0, !dbg !44
+// CHECK:STDOUT:   store i32 %n, ptr %.loc42.n, align 4, !dbg !44
+// CHECK:STDOUT:   call void @_Z4TakeI6PackedEvRT_(ptr %a.var), !dbg !45
+// CHECK:STDOUT:   ret void, !dbg !46
+// CHECK:STDOUT: }
+// CHECK:STDOUT:
+// CHECK:STDOUT: ; Function Attrs: alwaysinline mustprogress nounwind uwtable
+// CHECK:STDOUT: define internal void @_ZN6PackedC1Ev.carbon_thunk.(ptr noundef %return) #1 {
+// CHECK:STDOUT: entry:
+// CHECK:STDOUT:   %return.addr = alloca ptr, align 8
+// CHECK:STDOUT:   store ptr %return, ptr %return.addr, align 8, !tbaa !47
+// CHECK:STDOUT:   %0 = load ptr, ptr %return.addr, align 8, !tbaa !47
+// CHECK:STDOUT:   ret void
+// CHECK:STDOUT: }
+// CHECK:STDOUT:
+// CHECK:STDOUT: ; Function Attrs: alwaysinline nounwind
+// CHECK:STDOUT: define void @"_COp:thunk:Default.ba085c8bae0456bc.Core:Packed.Cpp"(ptr sret([4 x i8]) %return) #2 !dbg !49 {
+// CHECK:STDOUT: entry:
+// CHECK:STDOUT:   call void @_ZN6PackedC1Ev.carbon_thunk.(ptr %return), !dbg !50
+// CHECK:STDOUT:   ret void, !dbg !50
+// CHECK:STDOUT: }
+// CHECK:STDOUT:
+// CHECK:STDOUT: declare void @_Z4TakeI6PackedEvRT_(ptr noundef nonnull align 1 dereferenceable(4)) #3
+// CHECK:STDOUT:
+// CHECK:STDOUT: ; Function Attrs: nocallback nofree nosync nounwind willreturn memory(argmem: readwrite)
+// CHECK:STDOUT: declare void @llvm.lifetime.start.p0(ptr captures(none)) #4
+// CHECK:STDOUT:
+// CHECK:STDOUT: ; Function Attrs: nounwind
+// CHECK:STDOUT: define linkonce_odr void @"_COp.cbe5dd53b28eb3d1:DefaultOrUnformed.Core.53704887462f6065"(ptr sret([4 x i8]) %return) #0 !dbg !51 {
+// CHECK:STDOUT:   call void @"_COp:thunk:Default.381601f5a2bd2e81.Core:NaturallyAligned.Cpp"(ptr %return), !dbg !53
+// CHECK:STDOUT:   ret void, !dbg !54
+// CHECK:STDOUT: }
+// CHECK:STDOUT:
+// CHECK:STDOUT: ; Function Attrs: nounwind
+// CHECK:STDOUT: define linkonce_odr void @"_COp.cbe5dd53b28eb3d1:DefaultOrUnformed.Core.f529dae788690cbe"(ptr sret([16 x i8]) %return) #0 !dbg !55 {
+// CHECK:STDOUT:   call void @"_COp:thunk:Default.6ca50d719a15fa24.Core:ExtraAlignment.Cpp"(ptr %return), !dbg !56
+// CHECK:STDOUT:   ret void, !dbg !57
+// CHECK:STDOUT: }
+// CHECK:STDOUT:
+// CHECK:STDOUT: ; Function Attrs: nounwind
+// CHECK:STDOUT: define linkonce_odr void @"_COp.cbe5dd53b28eb3d1:DefaultOrUnformed.Core.ee398c9a806dbb35"(ptr sret([4 x i8]) %return) #0 !dbg !58 {
+// CHECK:STDOUT:   call void @"_COp:thunk:Default.ba085c8bae0456bc.Core:Packed.Cpp"(ptr %return), !dbg !59
+// CHECK:STDOUT:   ret void, !dbg !60
+// CHECK:STDOUT: }
+// CHECK:STDOUT:
+// CHECK:STDOUT: ; uselistorder directives
+// CHECK:STDOUT: uselistorder ptr @llvm.lifetime.start.p0, { 2, 1, 0 }
+// CHECK:STDOUT:
+// CHECK:STDOUT: attributes #0 = { nounwind }
+// CHECK:STDOUT: attributes #1 = { alwaysinline mustprogress nounwind uwtable "min-legal-vector-width"="0" "no-trapping-math"="true" "stack-protector-buffer-size"="8" "target-cpu"="x86-64" "target-features"="+cmov,+cx8,+fxsr,+mmx,+sse,+sse2,+x87" "tune-cpu"="generic" }
+// CHECK:STDOUT: attributes #2 = { alwaysinline nounwind }
+// CHECK:STDOUT: attributes #3 = { "no-trapping-math"="true" "stack-protector-buffer-size"="8" "target-cpu"="x86-64" "target-features"="+cmov,+cx8,+fxsr,+mmx,+sse,+sse2,+x87" "tune-cpu"="generic" }
+// CHECK:STDOUT: attributes #4 = { nocallback nofree nosync nounwind willreturn memory(argmem: readwrite) }
+// CHECK:STDOUT:
+// CHECK:STDOUT: !llvm.module.flags = !{!0, !1, !2, !3, !4}
+// CHECK:STDOUT: !llvm.dbg.cu = !{!5}
+// CHECK:STDOUT: !llvm.errno.tbaa = !{!7}
+// CHECK:STDOUT:
+// CHECK:STDOUT: !0 = !{i32 7, !"Dwarf Version", i32 5}
+// CHECK:STDOUT: !1 = !{i32 2, !"Debug Info Version", i32 3}
+// CHECK:STDOUT: !2 = !{i32 8, !"PIC Level", i32 2}
+// CHECK:STDOUT: !3 = !{i32 7, !"PIE Level", i32 2}
+// CHECK:STDOUT: !4 = !{i32 7, !"uwtable", i32 2}
+// CHECK:STDOUT: !5 = distinct !DICompileUnit(language: DW_LANG_C_plus_plus, file: !6, producer: "carbon", isOptimized: false, runtimeVersion: 0, emissionKind: FullDebug)
+// CHECK:STDOUT: !6 = !DIFile(filename: "alignment.carbon", directory: "")
+// CHECK:STDOUT: !7 = !{!8, !8, i64 0}
+// CHECK:STDOUT: !8 = !{!"int", !9, i64 0}
+// CHECK:STDOUT: !9 = !{!"omnipotent char", !10, i64 0}
+// CHECK:STDOUT: !10 = !{!"Simple C++ TBAA"}
+// CHECK:STDOUT: !11 = distinct !DISubprogram(name: "NaturallyAligned", linkageName: "_CNaturallyAligned.Main", scope: null, file: !6, line: 23, type: !12, spFlags: DISPFlagDefinition, unit: !5, retainedNodes: !15)
+// CHECK:STDOUT: !12 = !DISubroutineType(types: !13)
+// CHECK:STDOUT: !13 = !{null, !14}
+// CHECK:STDOUT: !14 = !DIBasicType(name: "int", size: 32, encoding: DW_ATE_signed)
+// CHECK:STDOUT: !15 = !{!16}
+// CHECK:STDOUT: !16 = !DILocalVariable(arg: 1, scope: !11, type: !14)
+// CHECK:STDOUT: !17 = !DILocation(line: 24, column: 3, scope: !11)
+// CHECK:STDOUT: !18 = !DILocation(line: 25, column: 3, scope: !11)
+// CHECK:STDOUT: !19 = !DILocation(line: 26, column: 3, scope: !11)
+// CHECK:STDOUT: !20 = !DILocation(line: 23, column: 1, scope: !11)
+// CHECK:STDOUT: !21 = !{!22, !22, i64 0}
+// CHECK:STDOUT: !22 = !{!"p1 _ZTS16NaturallyAligned", !23, i64 0}
+// CHECK:STDOUT: !23 = !{!"any pointer", !9, i64 0}
+// CHECK:STDOUT: !24 = distinct !DISubprogram(name: "Op", linkageName: "_COp:thunk:Default.381601f5a2bd2e81.Core:NaturallyAligned.Cpp", scope: null, file: !6, line: 7, type: !25, spFlags: DISPFlagDefinition, unit: !5)
+// CHECK:STDOUT: !25 = !DISubroutineType(types: !26)
+// CHECK:STDOUT: !26 = !{!27}
+// CHECK:STDOUT: !27 = !DIDerivedType(tag: DW_TAG_pointer_type, baseType: null, size: 64)
+// CHECK:STDOUT: !28 = !DILocation(line: 7, column: 8, scope: !24)
+// CHECK:STDOUT: !29 = distinct !DISubprogram(name: "ExtraAlignment", linkageName: "_CExtraAlignment.Main", scope: null, file: !6, line: 29, type: !12, spFlags: DISPFlagDefinition, unit: !5, retainedNodes: !30)
+// CHECK:STDOUT: !30 = !{!31}
+// CHECK:STDOUT: !31 = !DILocalVariable(arg: 1, scope: !29, type: !14)
+// CHECK:STDOUT: !32 = !DILocation(line: 30, column: 3, scope: !29)
+// CHECK:STDOUT: !33 = !DILocation(line: 33, column: 3, scope: !29)
+// CHECK:STDOUT: !34 = !DILocation(line: 34, column: 3, scope: !29)
+// CHECK:STDOUT: !35 = !DILocation(line: 29, column: 1, scope: !29)
+// CHECK:STDOUT: !36 = !{!37, !37, i64 0}
+// CHECK:STDOUT: !37 = !{!"p1 _ZTS14ExtraAlignment", !23, i64 0}
+// CHECK:STDOUT: !38 = distinct !DISubprogram(name: "Op", linkageName: "_COp:thunk:Default.6ca50d719a15fa24.Core:ExtraAlignment.Cpp", scope: null, file: !6, line: 11, type: !25, spFlags: DISPFlagDefinition, unit: !5)
+// CHECK:STDOUT: !39 = !DILocation(line: 11, column: 20, scope: !38)
+// CHECK:STDOUT: !40 = distinct !DISubprogram(name: "Packed", linkageName: "_CPacked.Main", scope: null, file: !6, line: 37, type: !12, spFlags: DISPFlagDefinition, unit: !5, retainedNodes: !41)
+// CHECK:STDOUT: !41 = !{!42}
+// CHECK:STDOUT: !42 = !DILocalVariable(arg: 1, scope: !40, type: !14)
+// CHECK:STDOUT: !43 = !DILocation(line: 38, column: 3, scope: !40)
+// CHECK:STDOUT: !44 = !DILocation(line: 42, column: 3, scope: !40)
+// CHECK:STDOUT: !45 = !DILocation(line: 43, column: 3, scope: !40)
+// CHECK:STDOUT: !46 = !DILocation(line: 37, column: 1, scope: !40)
+// CHECK:STDOUT: !47 = !{!48, !48, i64 0}
+// CHECK:STDOUT: !48 = !{!"p1 _ZTS6Packed", !23, i64 0}
+// CHECK:STDOUT: !49 = distinct !DISubprogram(name: "Op", linkageName: "_COp:thunk:Default.ba085c8bae0456bc.Core:Packed.Cpp", scope: null, file: !6, line: 15, type: !25, spFlags: DISPFlagDefinition, unit: !5)
+// CHECK:STDOUT: !50 = !DILocation(line: 15, column: 32, scope: !49)
+// CHECK:STDOUT: !51 = distinct !DISubprogram(name: "Op", linkageName: "_COp.cbe5dd53b28eb3d1:DefaultOrUnformed.Core.53704887462f6065", scope: null, file: !52, line: 9, type: !25, spFlags: DISPFlagDefinition, unit: !5)
+// CHECK:STDOUT: !52 = !DIFile(filename: "min_prelude/parts/default.carbon", directory: "")
+// CHECK:STDOUT: !53 = !DILocation(line: 9, column: 28, scope: !51)
+// CHECK:STDOUT: !54 = !DILocation(line: 9, column: 21, scope: !51)
+// CHECK:STDOUT: !55 = distinct !DISubprogram(name: "Op", linkageName: "_COp.cbe5dd53b28eb3d1:DefaultOrUnformed.Core.f529dae788690cbe", scope: null, file: !52, line: 9, type: !25, spFlags: DISPFlagDefinition, unit: !5)
+// CHECK:STDOUT: !56 = !DILocation(line: 9, column: 28, scope: !55)
+// CHECK:STDOUT: !57 = !DILocation(line: 9, column: 21, scope: !55)
+// CHECK:STDOUT: !58 = distinct !DISubprogram(name: "Op", linkageName: "_COp.cbe5dd53b28eb3d1:DefaultOrUnformed.Core.ee398c9a806dbb35", scope: null, file: !52, line: 9, type: !25, spFlags: DISPFlagDefinition, unit: !5)
+// CHECK:STDOUT: !59 = !DILocation(line: 9, column: 28, scope: !58)
+// CHECK:STDOUT: !60 = !DILocation(line: 9, column: 21, scope: !58)
diff --git a/toolchain/lower/testdata/interop/cpp/constructor.carbon b/toolchain/lower/testdata/interop/cpp/constructor.carbon
index 9895e16b34d9..5de2c0d5e439 100644
--- a/toolchain/lower/testdata/interop/cpp/constructor.carbon
+++ b/toolchain/lower/testdata/interop/cpp/constructor.carbon
@@ -179,7 +179,7 @@ fn Four() {
 // CHECK:STDOUT: ; Function Attrs: nounwind
 // CHECK:STDOUT: define void @_CF.Main() #0 !dbg !11 {
 // CHECK:STDOUT: entry:
-// CHECK:STDOUT:   %.loc7_26.1.temp = alloca [8 x i8], align 1, !dbg !14
+// CHECK:STDOUT:   %.loc7_26.1.temp = alloca [8 x i8], align 4, !dbg !14
 // CHECK:STDOUT:   call void @llvm.lifetime.start.p0(ptr %.loc7_26.1.temp), !dbg !14
 // CHECK:STDOUT:   call void @_ZN1CC1Ev.carbon_thunk.(ptr %.loc7_26.1.temp), !dbg !14
 // CHECK:STDOUT:   ret void, !dbg !15
@@ -198,7 +198,7 @@ fn Four() {
 // CHECK:STDOUT: ; Function Attrs: nounwind
 // CHECK:STDOUT: define void @_CG.Main() #0 !dbg !19 {
 // CHECK:STDOUT: entry:
-// CHECK:STDOUT:   %.loc11_19.2.temp = alloca [8 x i8], align 1, !dbg !20
+// CHECK:STDOUT:   %.loc11_19.2.temp = alloca [8 x i8], align 4, !dbg !20
 // CHECK:STDOUT:   call void @llvm.lifetime.start.p0(ptr %.loc11_19.2.temp), !dbg !20
 // CHECK:STDOUT:   call void @_ZN1CC1Ev.carbon_thunk_tuple.(ptr %.loc11_19.2.temp), !dbg !20
 // CHECK:STDOUT:   ret void, !dbg !21
@@ -279,7 +279,7 @@ fn Four() {
 // CHECK:STDOUT: ; Function Attrs: nounwind
 // CHECK:STDOUT: define void @_CF.Main() #0 !dbg !11 {
 // CHECK:STDOUT: entry:
-// CHECK:STDOUT:   %_.var = alloca [8 x i8], align 1, !dbg !14
+// CHECK:STDOUT:   %_.var = alloca [8 x i8], align 4, !dbg !14
 // CHECK:STDOUT:   call void @llvm.lifetime.start.p0(ptr %_.var), !dbg !14
 // CHECK:STDOUT:   call void @"_COp.cbe5dd53b28eb3d1:DefaultOrUnformed.Core.4fdc745d4b6d0e3c"(ptr %_.var), !dbg !14
 // CHECK:STDOUT:   ret void, !dbg !15
@@ -381,10 +381,10 @@ fn Four() {
 // CHECK:STDOUT: ; Function Attrs: nounwind
 // CHECK:STDOUT: define void @_CF.Main() #0 !dbg !11 {
 // CHECK:STDOUT: entry:
-// CHECK:STDOUT:   %.loc8_65.1.temp = alloca [4 x i8], align 1, !dbg !14
-// CHECK:STDOUT:   %_.var.loc9 = alloca [4 x i8], align 1, !dbg !15
-// CHECK:STDOUT:   %.loc12_65.1.temp = alloca [4 x i8], align 1, !dbg !16
-// CHECK:STDOUT:   %_.var.loc13 = alloca [4 x i8], align 1, !dbg !17
+// CHECK:STDOUT:   %.loc8_65.1.temp = alloca [4 x i8], align 4, !dbg !14
+// CHECK:STDOUT:   %_.var.loc9 = alloca [4 x i8], align 4, !dbg !15
+// CHECK:STDOUT:   %.loc12_65.1.temp = alloca [4 x i8], align 4, !dbg !16
+// CHECK:STDOUT:   %_.var.loc13 = alloca [4 x i8], align 4, !dbg !17
 // CHECK:STDOUT:   call void @llvm.lifetime.start.p0(ptr %.loc8_65.1.temp), !dbg !14
 // CHECK:STDOUT:   call void @_ZN26ImplicitlyDefaultedDefaultC1Ev.carbon_thunk.(ptr %.loc8_65.1.temp), !dbg !14
 // CHECK:STDOUT:   call void @llvm.lifetime.start.p0(ptr %_.var.loc9), !dbg !15
@@ -532,7 +532,7 @@ fn Four() {
 // CHECK:STDOUT: ; Function Attrs: nounwind
 // CHECK:STDOUT: define void @_CCopy.Main(ptr sret([4 x i8]) %return, ptr %c) #0 !dbg !11 {
 // CHECK:STDOUT: entry:
-// CHECK:STDOUT:   %.loc7_10.1.temp = alloca [4 x i8], align 1, !dbg !17
+// CHECK:STDOUT:   %.loc7_10.1.temp = alloca [4 x i8], align 4, !dbg !17
 // CHECK:STDOUT:   call void @llvm.lifetime.start.p0(ptr %.loc7_10.1.temp), !dbg !17
 // CHECK:STDOUT:   call void @_ZN4CopyC1ERKS_.carbon_thunk._(ptr %c, ptr %return), !dbg !17
 // CHECK:STDOUT:   ret void, !dbg !18
@@ -631,7 +631,7 @@ fn Four() {
 // CHECK:STDOUT: ; Function Attrs: nounwind
 // CHECK:STDOUT: define void @_CF.Main() #0 !dbg !11 {
 // CHECK:STDOUT: entry:
-// CHECK:STDOUT:   %.loc7_44.1.temp = alloca [8 x i8], align 1, !dbg !14
+// CHECK:STDOUT:   %.loc7_44.1.temp = alloca [8 x i8], align 8, !dbg !14
 // CHECK:STDOUT:   call void @llvm.lifetime.start.p0(ptr %.loc7_44.1.temp), !dbg !14
 // CHECK:STDOUT:   call void @_ZN7DerivedC1Ev.carbon_thunk.(ptr %.loc7_44.1.temp), !dbg !14
 // CHECK:STDOUT:   ret void, !dbg !15
diff --git a/toolchain/lower/testdata/interop/cpp/parameters.carbon b/toolchain/lower/testdata/interop/cpp/parameters.carbon
index 500b891eb701..67b05b6ac1e0 100644
--- a/toolchain/lower/testdata/interop/cpp/parameters.carbon
+++ b/toolchain/lower/testdata/interop/cpp/parameters.carbon
@@ -365,7 +365,7 @@ fn PassValueExpr(y: Cpp.Y) {
 // CHECK:STDOUT: ; Function Attrs: nounwind
 // CHECK:STDOUT: define void @_CTest.Main() #0 !dbg !11 {
 // CHECK:STDOUT: entry:
-// CHECK:STDOUT:   %x.var = alloca [12 x i8], align 1, !dbg !14
+// CHECK:STDOUT:   %x.var = alloca [12 x i8], align 4, !dbg !14
 // CHECK:STDOUT:   call void @llvm.lifetime.start.p0(ptr %x.var), !dbg !14
 // CHECK:STDOUT:   call void @"_COp.cbe5dd53b28eb3d1:DefaultOrUnformed.Core.1cc04ab0b0144e39"(ptr %x.var), !dbg !14
 // CHECK:STDOUT:   %.loc8_4.a = getelementptr inbounds nuw [12 x i8], ptr %x.var, i32 0, i32 0, !dbg !15
@@ -484,7 +484,7 @@ fn PassValueExpr(y: Cpp.Y) {
 // CHECK:STDOUT: ; Function Attrs: nounwind
 // CHECK:STDOUT: define void @_CPassRefExpr.Main() #0 !dbg !11 {
 // CHECK:STDOUT: entry:
-// CHECK:STDOUT:   %y.var = alloca [12 x i8], align 1, !dbg !14
+// CHECK:STDOUT:   %y.var = alloca [12 x i8], align 4, !dbg !14
 // CHECK:STDOUT:   call void @llvm.lifetime.start.p0(ptr %y.var), !dbg !14
 // CHECK:STDOUT:   %.loc8_4.a = getelementptr inbounds nuw [12 x i8], ptr %y.var, i32 0, i32 0, !dbg !15
 // CHECK:STDOUT:   store i32 1, ptr %.loc8_4.a, align 4, !dbg !15
@@ -513,7 +513,7 @@ fn PassValueExpr(y: Cpp.Y) {
 // CHECK:STDOUT: ; Function Attrs: nounwind
 // CHECK:STDOUT: define void @_CPassInitExpr.Main() #0 !dbg !23 {
 // CHECK:STDOUT: entry:
-// CHECK:STDOUT:   %.loc17_24.1.temp = alloca [12 x i8], align 1, !dbg !24
+// CHECK:STDOUT:   %.loc17_24.1.temp = alloca [12 x i8], align 4, !dbg !24
 // CHECK:STDOUT:   call void @llvm.lifetime.start.p0(ptr %.loc17_24.1.temp), !dbg !24
 // CHECK:STDOUT:   call void @_CMake.Main(ptr %.loc17_24.1.temp), !dbg !24
 // CHECK:STDOUT:   call void @_Z11pass_struct1Y.carbon_thunk._(ptr %.loc17_24.1.temp), !dbg !25
diff --git a/toolchain/lower/testdata/interop/cpp/reference.carbon b/toolchain/lower/testdata/interop/cpp/reference.carbon
index 678c27d3edf9..e05eb52526e8 100644
--- a/toolchain/lower/testdata/interop/cpp/reference.carbon
+++ b/toolchain/lower/testdata/interop/cpp/reference.carbon
@@ -138,8 +138,8 @@ fn GetRefs() {
 // CHECK:STDOUT: ; Function Attrs: nounwind
 // CHECK:STDOUT: define void @_CPassRefs.Main() #0 !dbg !11 {
 // CHECK:STDOUT: entry:
-// CHECK:STDOUT:   %c.var = alloca {}, align 8, !dbg !14
-// CHECK:STDOUT:   %_.var.1 = alloca {}, align 8, !dbg !15
+// CHECK:STDOUT:   %c.var = alloca {}, align 1, !dbg !14
+// CHECK:STDOUT:   %_.var.1 = alloca {}, align 1, !dbg !15
 // CHECK:STDOUT:   %n.var = alloca i32, align 4, !dbg !16
 // CHECK:STDOUT:   %_.var.2 = alloca i32, align 4, !dbg !17
 // CHECK:STDOUT:   %.loc25_23.2.temp = alloca i32, align 4, !dbg !18
@@ -327,8 +327,8 @@ fn GetRefs() {
 // CHECK:STDOUT: ; Function Attrs: nounwind
 // CHECK:STDOUT: define void @_CPassRefs.Main() #0 !dbg !11 {
 // CHECK:STDOUT: entry:
-// CHECK:STDOUT:   %c.var = alloca {}, align 8, !dbg !14
-// CHECK:STDOUT:   %.loc20_18.2.temp = alloca {}, align 8, !dbg !15
+// CHECK:STDOUT:   %c.var = alloca {}, align 1, !dbg !14
+// CHECK:STDOUT:   %.loc20_18.2.temp = alloca {}, align 1, !dbg !15
 // CHECK:STDOUT:   %n.var = alloca i32, align 4, !dbg !16
 // CHECK:STDOUT:   %_.var = alloca i32, align 4, !dbg !17
 // CHECK:STDOUT:   %.loc26_23.2.temp = alloca i32, align 4, !dbg !18
diff --git a/toolchain/lower/testdata/interop/cpp/return.carbon b/toolchain/lower/testdata/interop/cpp/return.carbon
index cafb57c85d93..5ebf930db7ae 100644
--- a/toolchain/lower/testdata/interop/cpp/return.carbon
+++ b/toolchain/lower/testdata/interop/cpp/return.carbon
@@ -574,7 +574,7 @@ fn Call(x: Cpp.D) -> Cpp.C {
 // CHECK:STDOUT: ; Function Attrs: nounwind
 // CHECK:STDOUT: define void @_CLet.Main() #0 !dbg !20 {
 // CHECK:STDOUT: entry:
-// CHECK:STDOUT:   %.loc9_27.1.temp = alloca [16 x i8], align 1, !dbg !23
+// CHECK:STDOUT:   %.loc9_27.1.temp = alloca [16 x i8], align 8, !dbg !23
 // CHECK:STDOUT:   call void @llvm.lifetime.start.p0(ptr %.loc9_27.1.temp), !dbg !23
 // CHECK:STDOUT:   call void @_Z4Makev.carbon_thunk.(ptr %.loc9_27.1.temp), !dbg !23
 // CHECK:STDOUT:   call void @_ZN1XD1Ev(ptr %.loc9_27.1.temp), !dbg !23
@@ -587,7 +587,7 @@ fn Call(x: Cpp.D) -> Cpp.C {
 // CHECK:STDOUT: ; Function Attrs: nounwind
 // CHECK:STDOUT: define void @_CVar.Main() #0 !dbg !25 {
 // CHECK:STDOUT: entry:
-// CHECK:STDOUT:   %_.var = alloca [16 x i8], align 1, !dbg !26
+// CHECK:STDOUT:   %_.var = alloca [16 x i8], align 8, !dbg !26
 // CHECK:STDOUT:   call void @llvm.lifetime.start.p0(ptr %_.var), !dbg !26
 // CHECK:STDOUT:   call void @_Z4Makev.carbon_thunk.(ptr %_.var), !dbg !27
 // CHECK:STDOUT:   call void @_ZN1XD1Ev(ptr %_.var), !dbg !26
diff --git a/toolchain/lower/testdata/interop/cpp/reverse/class.carbon b/toolchain/lower/testdata/interop/cpp/reverse/class.carbon
index f6b05f333b1e..c2549fa5ff22 100644
--- a/toolchain/lower/testdata/interop/cpp/reverse/class.carbon
+++ b/toolchain/lower/testdata/interop/cpp/reverse/class.carbon
@@ -497,7 +497,7 @@ fn G() {
 // CHECK:STDOUT: ; Function Attrs: nounwind
 // CHECK:STDOUT: define void @_CG.Main() #2 !dbg !41 {
 // CHECK:STDOUT: entry:
-// CHECK:STDOUT:   %c.var = alloca { i32, i32 }, align 8, !dbg !44
+// CHECK:STDOUT:   %c.var = alloca { i32, i32 }, align 4, !dbg !44
 // CHECK:STDOUT:   call void @llvm.lifetime.start.p0(ptr %c.var), !dbg !44
 // CHECK:STDOUT:   %.loc19_29.3.a = getelementptr inbounds nuw { i32, i32 }, ptr %c.var, i32 0, i32 0, !dbg !45
 // CHECK:STDOUT:   %.loc19_29.6.b = getelementptr inbounds nuw { i32, i32 }, ptr %c.var, i32 0, i32 1, !dbg !45
diff --git a/toolchain/lower/testdata/interop/cpp/std_initializer_list.carbon b/toolchain/lower/testdata/interop/cpp/std_initializer_list.carbon
index 6dd456ac36e1..1b94f1166a10 100644
--- a/toolchain/lower/testdata/interop/cpp/std_initializer_list.carbon
+++ b/toolchain/lower/testdata/interop/cpp/std_initializer_list.carbon
@@ -134,7 +134,7 @@ fn InitNontrivialDtor() {
 // CHECK:STDOUT: ; Function Attrs: nounwind
 // CHECK:STDOUT: define void @_CInitDirectly.Main() #0 !dbg !11 {
 // CHECK:STDOUT: entry:
-// CHECK:STDOUT:   %_.var = alloca [16 x i8], align 1, !dbg !14
+// CHECK:STDOUT:   %_.var = alloca [16 x i8], align 8, !dbg !14
 // CHECK:STDOUT:   %.loc13_50.3.temp = alloca [3 x i32], align 4, !dbg !15
 // CHECK:STDOUT:   call void @llvm.lifetime.start.p0(ptr %_.var), !dbg !14
 // CHECK:STDOUT:   call void @llvm.lifetime.start.p0(ptr %.loc13_50.3.temp), !dbg !15
@@ -166,7 +166,7 @@ fn InitNontrivialDtor() {
 // CHECK:STDOUT: define void @_CInitVectorLike.Main() #0 !dbg !32 {
 // CHECK:STDOUT: entry:
 // CHECK:STDOUT:   %_.var = alloca [1 x i8], align 1, !dbg !33
-// CHECK:STDOUT:   %.loc18_36.2.temp = alloca [16 x i8], align 1, !dbg !34
+// CHECK:STDOUT:   %.loc18_36.2.temp = alloca [16 x i8], align 8, !dbg !34
 // CHECK:STDOUT:   %.loc18_36.4.temp = alloca [3 x i32], align 4, !dbg !34
 // CHECK:STDOUT:   call void @llvm.lifetime.start.p0(ptr %_.var), !dbg !33
 // CHECK:STDOUT:   call void @llvm.lifetime.start.p0(ptr %.loc18_36.2.temp), !dbg !34
@@ -216,7 +216,7 @@ fn InitNontrivialDtor() {
 // CHECK:STDOUT: ; Function Attrs: nounwind
 // CHECK:STDOUT: define void @_CInitNontrivialDtor.Main() #0 !dbg !45 {
 // CHECK:STDOUT: entry:
-// CHECK:STDOUT:   %_.var = alloca [16 x i8], align 1, !dbg !46
+// CHECK:STDOUT:   %_.var = alloca [16 x i8], align 8, !dbg !46
 // CHECK:STDOUT:   %.loc23_69.17.temp = alloca [3 x [1 x i8]], align 1, !dbg !47
 // CHECK:STDOUT:   call void @llvm.lifetime.start.p0(ptr %_.var), !dbg !46
 // CHECK:STDOUT:   call void @llvm.lifetime.start.p0(ptr %.loc23_69.17.temp), !dbg !47
@@ -382,7 +382,7 @@ fn InitNontrivialDtor() {
 // CHECK:STDOUT: ; Function Attrs: nounwind
 // CHECK:STDOUT: define void @_CInitDirectly.Main() #0 !dbg !11 {
 // CHECK:STDOUT: entry:
-// CHECK:STDOUT:   %_.var = alloca [16 x i8], align 1, !dbg !14
+// CHECK:STDOUT:   %_.var = alloca [16 x i8], align 8, !dbg !14
 // CHECK:STDOUT:   %.loc13_50.3.temp = alloca [3 x i32], align 4, !dbg !15
 // CHECK:STDOUT:   call void @llvm.lifetime.start.p0(ptr %_.var), !dbg !14
 // CHECK:STDOUT:   call void @llvm.lifetime.start.p0(ptr %.loc13_50.3.temp), !dbg !15
@@ -414,7 +414,7 @@ fn InitNontrivialDtor() {
 // CHECK:STDOUT: define void @_CInitVectorLike.Main() #0 !dbg !32 {
 // CHECK:STDOUT: entry:
 // CHECK:STDOUT:   %_.var = alloca [1 x i8], align 1, !dbg !33
-// CHECK:STDOUT:   %.loc18_36.2.temp = alloca [16 x i8], align 1, !dbg !34
+// CHECK:STDOUT:   %.loc18_36.2.temp = alloca [16 x i8], align 8, !dbg !34
 // CHECK:STDOUT:   %.loc18_36.4.temp = alloca [3 x i32], align 4, !dbg !34
 // CHECK:STDOUT:   call void @llvm.lifetime.start.p0(ptr %_.var), !dbg !33
 // CHECK:STDOUT:   call void @llvm.lifetime.start.p0(ptr %.loc18_36.2.temp), !dbg !34
@@ -464,7 +464,7 @@ fn InitNontrivialDtor() {
 // CHECK:STDOUT: ; Function Attrs: nounwind
 // CHECK:STDOUT: define void @_CInitNontrivialDtor.Main() #0 !dbg !47 {
 // CHECK:STDOUT: entry:
-// CHECK:STDOUT:   %_.var = alloca [16 x i8], align 1, !dbg !48
+// CHECK:STDOUT:   %_.var = alloca [16 x i8], align 8, !dbg !48
 // CHECK:STDOUT:   %.loc23_69.17.temp = alloca [3 x [1 x i8]], align 1, !dbg !49
 // CHECK:STDOUT:   call void @llvm.lifetime.start.p0(ptr %_.var), !dbg !48
 // CHECK:STDOUT:   call void @llvm.lifetime.start.p0(ptr %.loc23_69.17.temp), !dbg !49
diff --git a/toolchain/lower/testdata/interop/cpp/template.carbon b/toolchain/lower/testdata/interop/cpp/template.carbon
index da13de41b9ad..8804fadc0871 100644
--- a/toolchain/lower/testdata/interop/cpp/template.carbon
+++ b/toolchain/lower/testdata/interop/cpp/template.carbon
@@ -269,7 +269,7 @@ fn Call3() {
 // CHECK:STDOUT: ; Function Attrs: nounwind
 // CHECK:STDOUT: define void @_CCall1.Main() #0 !dbg !11 {
 // CHECK:STDOUT: entry:
-// CHECK:STDOUT:   %.loc12_12.2.temp = alloca {}, align 8, !dbg !14
+// CHECK:STDOUT:   %.loc12_12.2.temp = alloca {}, align 1, !dbg !14
 // CHECK:STDOUT:   call void @llvm.lifetime.start.p0(ptr %.loc12_12.2.temp), !dbg !14
 // CHECK:STDOUT:   call void @_Z3fooIJEEv1XDpT_.carbon_thunk._(ptr @X.val.loc12_14.3), !dbg !15
 // CHECK:STDOUT:   ret void, !dbg !16
@@ -289,7 +289,7 @@ fn Call3() {
 // CHECK:STDOUT: ; Function Attrs: nounwind
 // CHECK:STDOUT: define void @_CCall2.Main() #0 !dbg !20 {
 // CHECK:STDOUT: entry:
-// CHECK:STDOUT:   %.loc18_12.2.temp = alloca {}, align 8, !dbg !21
+// CHECK:STDOUT:   %.loc18_12.2.temp = alloca {}, align 1, !dbg !21
 // CHECK:STDOUT:   call void @llvm.lifetime.start.p0(ptr %.loc18_12.2.temp), !dbg !21
 // CHECK:STDOUT:   call void @_Z3fooIJiEEv1XDpT_.carbon_thunk.__(ptr @X.val.loc12_14.3, i32 2), !dbg !22
 // CHECK:STDOUT:   ret void, !dbg !23
@@ -312,7 +312,7 @@ fn Call3() {
 // CHECK:STDOUT: ; Function Attrs: nounwind
 // CHECK:STDOUT: define void @_CCall3.Main() #0 !dbg !24 {
 // CHECK:STDOUT: entry:
-// CHECK:STDOUT:   %.loc24_12.2.temp = alloca {}, align 8, !dbg !25
+// CHECK:STDOUT:   %.loc24_12.2.temp = alloca {}, align 1, !dbg !25
 // CHECK:STDOUT:   call void @llvm.lifetime.start.p0(ptr %.loc24_12.2.temp), !dbg !25
 // CHECK:STDOUT:   call void @_Z3fooIJiiEEv1XDpT_.carbon_thunk.___(ptr @X.val.loc12_14.3, i32 2, i32 3), !dbg !26
 // CHECK:STDOUT:   ret void, !dbg !27
diff --git a/toolchain/lower/testdata/interop/cpp/virtual_base.carbon b/toolchain/lower/testdata/interop/cpp/virtual_base.carbon
index 8543a080f5cc..9727b60bae60 100644
--- a/toolchain/lower/testdata/interop/cpp/virtual_base.carbon
+++ b/toolchain/lower/testdata/interop/cpp/virtual_base.carbon
@@ -111,7 +111,7 @@ fn AccessD(d: Cpp.D) -> i32 {
 // CHECK:STDOUT: ; Function Attrs: nounwind
 // CHECK:STDOUT: define void @_CMake.Main() #0 !dbg !11 {
 // CHECK:STDOUT: entry:
-// CHECK:STDOUT:   %_.var = alloca [40 x i8], align 1, !dbg !14
+// CHECK:STDOUT:   %_.var = alloca [40 x i8], align 8, !dbg !14
 // CHECK:STDOUT:   call void @llvm.lifetime.start.p0(ptr %_.var), !dbg !14
 // CHECK:STDOUT:   call void @_ZN1DC1Ev.carbon_thunk.(ptr %_.var), !dbg !15
 // CHECK:STDOUT:   ret void, !dbg !16
diff --git a/toolchain/lower/testdata/let/copy_value_rep.carbon b/toolchain/lower/testdata/let/copy_value_rep.carbon
index df7666bc2c99..d8696f028831 100644
--- a/toolchain/lower/testdata/let/copy_value_rep.carbon
+++ b/toolchain/lower/testdata/let/copy_value_rep.carbon
@@ -30,7 +30,7 @@ fn Run() -> i32 {
 // CHECK:STDOUT: ; Function Attrs: nounwind
 // CHECK:STDOUT: define i32 @main() #0 !dbg !4 {
 // CHECK:STDOUT: entry:
-// CHECK:STDOUT:   %x.var = alloca { i32 }, align 8, !dbg !8
+// CHECK:STDOUT:   %x.var = alloca { i32 }, align 4, !dbg !8
 // CHECK:STDOUT:   call void @llvm.lifetime.start.p0(ptr %x.var), !dbg !8
 // CHECK:STDOUT:   %.loc18_21.3.a = getelementptr inbounds nuw { i32 }, ptr %x.var, i32 0, i32 0, !dbg !9
 // CHECK:STDOUT:   call void @llvm.memcpy.p0.p0.i64(ptr align 4 %x.var, ptr align 4 @X.val.loc18_3, i64 4, i1 false), !dbg !8
diff --git a/toolchain/lower/testdata/let/tuple.carbon b/toolchain/lower/testdata/let/tuple.carbon
index f1c243dd7b4c..6163b0db6f75 100644
--- a/toolchain/lower/testdata/let/tuple.carbon
+++ b/toolchain/lower/testdata/let/tuple.carbon
@@ -26,44 +26,47 @@ fn F() -> i32 {
 // CHECK:STDOUT: ; Function Attrs: nounwind
 // CHECK:STDOUT: define i32 @_CF.Main() #0 !dbg !4 {
 // CHECK:STDOUT: entry:
-// CHECK:STDOUT:   %a.var = alloca { i32, i32, i32 }, align 8, !dbg !8
-// CHECK:STDOUT:   %b.var = alloca { i32, i32 }, align 8, !dbg !9
+// CHECK:STDOUT:   %a.var = alloca { i32, i32, i32 }, align 4, !dbg !8
+// CHECK:STDOUT:   %b.var = alloca { i32, i32 }, align 4, !dbg !9
+// CHECK:STDOUT:   %tuple.loc16_43 = alloca { i32, i32, i32 }, align 4, !dbg !10
+// CHECK:STDOUT:   %tuple.loc16_46 = alloca { i32, i32 }, align 4, !dbg !11
+// CHECK:STDOUT:   %tuple.loc16_47 = alloca { ptr, ptr }, align 8, !dbg !12
 // CHECK:STDOUT:   call void @llvm.lifetime.start.p0(ptr %a.var), !dbg !8
-// CHECK:STDOUT:   %tuple.elem0.loc14.tuple.elem = getelementptr inbounds nuw { i32, i32, i32 }, ptr %a.var, i32 0, i32 0, !dbg !10
-// CHECK:STDOUT:   %tuple.elem1.loc14.tuple.elem = getelementptr inbounds nuw { i32, i32, i32 }, ptr %a.var, i32 0, i32 1, !dbg !10
-// CHECK:STDOUT:   %tuple.elem2.loc14.tuple.elem = getelementptr inbounds nuw { i32, i32, i32 }, ptr %a.var, i32 0, i32 2, !dbg !10
+// CHECK:STDOUT:   %tuple.elem0.loc14.tuple.elem = getelementptr inbounds nuw { i32, i32, i32 }, ptr %a.var, i32 0, i32 0, !dbg !13
+// CHECK:STDOUT:   %tuple.elem1.loc14.tuple.elem = getelementptr inbounds nuw { i32, i32, i32 }, ptr %a.var, i32 0, i32 1, !dbg !13
+// CHECK:STDOUT:   %tuple.elem2.loc14.tuple.elem = getelementptr inbounds nuw { i32, i32, i32 }, ptr %a.var, i32 0, i32 2, !dbg !13
 // CHECK:STDOUT:   call void @llvm.memcpy.p0.p0.i64(ptr align 4 %a.var, ptr align 4 @tuple.8d2.loc14_3, i64 12, i1 false), !dbg !8
 // CHECK:STDOUT:   call void @llvm.lifetime.start.p0(ptr %b.var), !dbg !9
-// CHECK:STDOUT:   %tuple.elem0.loc15.tuple.elem = getelementptr inbounds nuw { i32, i32 }, ptr %b.var, i32 0, i32 0, !dbg !11
-// CHECK:STDOUT:   %tuple.elem1.loc15.tuple.elem = getelementptr inbounds nuw { i32, i32 }, ptr %b.var, i32 0, i32 1, !dbg !11
+// CHECK:STDOUT:   %tuple.elem0.loc15.tuple.elem = getelementptr inbounds nuw { i32, i32 }, ptr %b.var, i32 0, i32 0, !dbg !14
+// CHECK:STDOUT:   %tuple.elem1.loc15.tuple.elem = getelementptr inbounds nuw { i32, i32 }, ptr %b.var, i32 0, i32 1, !dbg !14
 // CHECK:STDOUT:   call void @llvm.memcpy.p0.p0.i64(ptr align 4 %b.var, ptr align 4 @tuple.57b.loc15_3, i64 8, i1 false), !dbg !9
-// CHECK:STDOUT:   %tuple.elem0.loc16_43.tuple.elem = getelementptr inbounds nuw { i32, i32, i32 }, ptr %a.var, i32 0, i32 0, !dbg !12
-// CHECK:STDOUT:   %.loc16_43.1 = load i32, ptr %tuple.elem0.loc16_43.tuple.elem, align 4, !dbg !12
-// CHECK:STDOUT:   %tuple.elem1.loc16_43.tuple.elem = getelementptr inbounds nuw { i32, i32, i32 }, ptr %a.var, i32 0, i32 1, !dbg !12
-// CHECK:STDOUT:   %.loc16_43.2 = load i32, ptr %tuple.elem1.loc16_43.tuple.elem, align 4, !dbg !12
-// CHECK:STDOUT:   %tuple.elem2.loc16.tuple.elem = getelementptr inbounds nuw { i32, i32, i32 }, ptr %a.var, i32 0, i32 2, !dbg !12
-// CHECK:STDOUT:   %.loc16_43.3 = load i32, ptr %tuple.elem2.loc16.tuple.elem, align 4, !dbg !12
-// CHECK:STDOUT:   %tuple.loc16_43 = alloca { i32, i32, i32 }, align 8, !dbg !12
-// CHECK:STDOUT:   %tuple.loc16_431 = getelementptr inbounds nuw { i32, i32, i32 }, ptr %tuple.loc16_43, i32 0, i32 0, !dbg !12
-// CHECK:STDOUT:   store i32 %.loc16_43.1, ptr %tuple.loc16_431, align 4, !dbg !12
-// CHECK:STDOUT:   %tuple.loc16_432 = getelementptr inbounds nuw { i32, i32, i32 }, ptr %tuple.loc16_43, i32 0, i32 1, !dbg !12
-// CHECK:STDOUT:   store i32 %.loc16_43.2, ptr %tuple.loc16_432, align 4, !dbg !12
-// CHECK:STDOUT:   %tuple.loc16_433 = getelementptr inbounds nuw { i32, i32, i32 }, ptr %tuple.loc16_43, i32 0, i32 2, !dbg !12
-// CHECK:STDOUT:   store i32 %.loc16_43.3, ptr %tuple.loc16_433, align 4, !dbg !12
-// CHECK:STDOUT:   %tuple.elem0.loc16_46.tuple.elem = getelementptr inbounds nuw { i32, i32 }, ptr %b.var, i32 0, i32 0, !dbg !13
-// CHECK:STDOUT:   %.loc16_46.1 = load i32, ptr %tuple.elem0.loc16_46.tuple.elem, align 4, !dbg !13
-// CHECK:STDOUT:   %tuple.elem1.loc16_46.tuple.elem = getelementptr inbounds nuw { i32, i32 }, ptr %b.var, i32 0, i32 1, !dbg !13
-// CHECK:STDOUT:   %.loc16_46.2 = load i32, ptr %tuple.elem1.loc16_46.tuple.elem, align 4, !dbg !13
-// CHECK:STDOUT:   %tuple.loc16_46 = alloca { i32, i32 }, align 8, !dbg !13
-// CHECK:STDOUT:   %tuple.loc16_464 = getelementptr inbounds nuw { i32, i32 }, ptr %tuple.loc16_46, i32 0, i32 0, !dbg !13
-// CHECK:STDOUT:   store i32 %.loc16_46.1, ptr %tuple.loc16_464, align 4, !dbg !13
-// CHECK:STDOUT:   %tuple.loc16_465 = getelementptr inbounds nuw { i32, i32 }, ptr %tuple.loc16_46, i32 0, i32 1, !dbg !13
-// CHECK:STDOUT:   store i32 %.loc16_46.2, ptr %tuple.loc16_465, align 4, !dbg !13
-// CHECK:STDOUT:   %tuple.loc16_47 = alloca { ptr, ptr }, align 8, !dbg !14
-// CHECK:STDOUT:   %tuple.loc16_476 = getelementptr inbounds nuw { ptr, ptr }, ptr %tuple.loc16_47, i32 0, i32 0, !dbg !14
-// CHECK:STDOUT:   store ptr %tuple.loc16_43, ptr %tuple.loc16_476, align 8, !dbg !14
-// CHECK:STDOUT:   %tuple.loc16_477 = getelementptr inbounds nuw { ptr, ptr }, ptr %tuple.loc16_47, i32 0, i32 1, !dbg !14
-// CHECK:STDOUT:   store ptr %tuple.loc16_46, ptr %tuple.loc16_477, align 8, !dbg !14
+// CHECK:STDOUT:   %tuple.elem0.loc16_43.tuple.elem = getelementptr inbounds nuw { i32, i32, i32 }, ptr %a.var, i32 0, i32 0, !dbg !10
+// CHECK:STDOUT:   %.loc16_43.1 = load i32, ptr %tuple.elem0.loc16_43.tuple.elem, align 4, !dbg !10
+// CHECK:STDOUT:   %tuple.elem1.loc16_43.tuple.elem = getelementptr inbounds nuw { i32, i32, i32 }, ptr %a.var, i32 0, i32 1, !dbg !10
+// CHECK:STDOUT:   %.loc16_43.2 = load i32, ptr %tuple.elem1.loc16_43.tuple.elem, align 4, !dbg !10
+// CHECK:STDOUT:   %tuple.elem2.loc16.tuple.elem = getelementptr inbounds nuw { i32, i32, i32 }, ptr %a.var, i32 0, i32 2, !dbg !10
+// CHECK:STDOUT:   %.loc16_43.3 = load i32, ptr %tuple.elem2.loc16.tuple.elem, align 4, !dbg !10
+// CHECK:STDOUT:   call void @llvm.lifetime.start.p0(ptr %tuple.loc16_43), !dbg !10
+// CHECK:STDOUT:   %tuple.loc16_431 = getelementptr inbounds nuw { i32, i32, i32 }, ptr %tuple.loc16_43, i32 0, i32 0, !dbg !10
+// CHECK:STDOUT:   store i32 %.loc16_43.1, ptr %tuple.loc16_431, align 4, !dbg !10
+// CHECK:STDOUT:   %tuple.loc16_432 = getelementptr inbounds nuw { i32, i32, i32 }, ptr %tuple.loc16_43, i32 0, i32 1, !dbg !10
+// CHECK:STDOUT:   store i32 %.loc16_43.2, ptr %tuple.loc16_432, align 4, !dbg !10
+// CHECK:STDOUT:   %tuple.loc16_433 = getelementptr inbounds nuw { i32, i32, i32 }, ptr %tuple.loc16_43, i32 0, i32 2, !dbg !10
+// CHECK:STDOUT:   store i32 %.loc16_43.3, ptr %tuple.loc16_433, align 4, !dbg !10
+// CHECK:STDOUT:   %tuple.elem0.loc16_46.tuple.elem = getelementptr inbounds nuw { i32, i32 }, ptr %b.var, i32 0, i32 0, !dbg !11
+// CHECK:STDOUT:   %.loc16_46.1 = load i32, ptr %tuple.elem0.loc16_46.tuple.elem, align 4, !dbg !11
+// CHECK:STDOUT:   %tuple.elem1.loc16_46.tuple.elem = getelementptr inbounds nuw { i32, i32 }, ptr %b.var, i32 0, i32 1, !dbg !11
+// CHECK:STDOUT:   %.loc16_46.2 = load i32, ptr %tuple.elem1.loc16_46.tuple.elem, align 4, !dbg !11
+// CHECK:STDOUT:   call void @llvm.lifetime.start.p0(ptr %tuple.loc16_46), !dbg !11
+// CHECK:STDOUT:   %tuple.loc16_464 = getelementptr inbounds nuw { i32, i32 }, ptr %tuple.loc16_46, i32 0, i32 0, !dbg !11
+// CHECK:STDOUT:   store i32 %.loc16_46.1, ptr %tuple.loc16_464, align 4, !dbg !11
+// CHECK:STDOUT:   %tuple.loc16_465 = getelementptr inbounds nuw { i32, i32 }, ptr %tuple.loc16_46, i32 0, i32 1, !dbg !11
+// CHECK:STDOUT:   store i32 %.loc16_46.2, ptr %tuple.loc16_465, align 4, !dbg !11
+// CHECK:STDOUT:   call void @llvm.lifetime.start.p0(ptr %tuple.loc16_47), !dbg !12
+// CHECK:STDOUT:   %tuple.loc16_476 = getelementptr inbounds nuw { ptr, ptr }, ptr %tuple.loc16_47, i32 0, i32 0, !dbg !12
+// CHECK:STDOUT:   store ptr %tuple.loc16_43, ptr %tuple.loc16_476, align 8, !dbg !12
+// CHECK:STDOUT:   %tuple.loc16_477 = getelementptr inbounds nuw { ptr, ptr }, ptr %tuple.loc16_47, i32 0, i32 1, !dbg !12
+// CHECK:STDOUT:   store ptr %tuple.loc16_46, ptr %tuple.loc16_477, align 8, !dbg !12
 // CHECK:STDOUT:   %tuple.elem1.loc17_11.tuple.elem = getelementptr inbounds nuw { ptr, ptr }, ptr %tuple.loc16_47, i32 0, i32 1, !dbg !15
 // CHECK:STDOUT:   %tuple.elem1.loc17_11.tuple.elem.load = load ptr, ptr %tuple.elem1.loc17_11.tuple.elem, align 8, !dbg !15
 // CHECK:STDOUT:   %tuple.elem1.loc17_13.tuple.elem = getelementptr inbounds nuw { i32, i32 }, ptr %tuple.elem1.loc17_11.tuple.elem.load, i32 0, i32 1, !dbg !15
@@ -98,7 +101,7 @@ fn F() -> i32 {
 // CHECK:STDOUT: declare void @llvm.memcpy.p0.p0.i64(ptr noalias writeonly captures(none), ptr noalias readonly captures(none), i64, i1 immarg) #1
 // CHECK:STDOUT:
 // CHECK:STDOUT: ; uselistorder directives
-// CHECK:STDOUT: uselistorder ptr @llvm.lifetime.start.p0, { 1, 0 }
+// CHECK:STDOUT: uselistorder ptr @llvm.lifetime.start.p0, { 4, 3, 2, 1, 0 }
 // CHECK:STDOUT: uselistorder ptr @llvm.memcpy.p0.p0.i64, { 1, 0 }
 // CHECK:STDOUT:
 // CHECK:STDOUT: attributes #0 = { nounwind }
@@ -117,11 +120,11 @@ fn F() -> i32 {
 // CHECK:STDOUT: !7 = !DIBasicType(name: "int", size: 32, encoding: DW_ATE_signed)
 // CHECK:STDOUT: !8 = !DILocation(line: 14, column: 3, scope: !4)
 // CHECK:STDOUT: !9 = !DILocation(line: 15, column: 3, scope: !4)
-// CHECK:STDOUT: !10 = !DILocation(line: 14, column: 28, scope: !4)
-// CHECK:STDOUT: !11 = !DILocation(line: 15, column: 23, scope: !4)
-// CHECK:STDOUT: !12 = !DILocation(line: 16, column: 43, scope: !4)
-// CHECK:STDOUT: !13 = !DILocation(line: 16, column: 46, scope: !4)
-// CHECK:STDOUT: !14 = !DILocation(line: 16, column: 42, scope: !4)
+// CHECK:STDOUT: !10 = !DILocation(line: 16, column: 43, scope: !4)
+// CHECK:STDOUT: !11 = !DILocation(line: 16, column: 46, scope: !4)
+// CHECK:STDOUT: !12 = !DILocation(line: 16, column: 42, scope: !4)
+// CHECK:STDOUT: !13 = !DILocation(line: 14, column: 28, scope: !4)
+// CHECK:STDOUT: !14 = !DILocation(line: 15, column: 23, scope: !4)
 // CHECK:STDOUT: !15 = !DILocation(line: 17, column: 10, scope: !4)
 // CHECK:STDOUT: !16 = !DILocation(line: 17, column: 3, scope: !4)
 // CHECK:STDOUT: !17 = distinct !DISubprogram(name: "Op", linkageName: "_COp.94e3ca86614aba5d:core.Destroy.Core", scope: null, file: !3, line: 15, type: !18, spFlags: DISPFlagDefinition, unit: !2, retainedNodes: !20)
diff --git a/toolchain/lower/testdata/operators/assignment.carbon b/toolchain/lower/testdata/operators/assignment.carbon
index e83816b9f765..ddebb8eb048d 100644
--- a/toolchain/lower/testdata/operators/assignment.carbon
+++ b/toolchain/lower/testdata/operators/assignment.carbon
@@ -48,7 +48,7 @@ fn G() -> (i32, i32) {
 // CHECK:STDOUT: ; Function Attrs: nounwind
 // CHECK:STDOUT: define void @_CG.Main(ptr sret({ i32, i32 }) %return) #0 !dbg !18 {
 // CHECK:STDOUT: entry:
-// CHECK:STDOUT:   %b.var = alloca { i32, i32 }, align 8, !dbg !22
+// CHECK:STDOUT:   %b.var = alloca { i32, i32 }, align 4, !dbg !22
 // CHECK:STDOUT:   call void @llvm.lifetime.start.p0(ptr %b.var), !dbg !22
 // CHECK:STDOUT:   %tuple.elem0.loc21.tuple.elem = getelementptr inbounds nuw { i32, i32 }, ptr %b.var, i32 0, i32 0, !dbg !23
 // CHECK:STDOUT:   %tuple.elem1.loc21.tuple.elem = getelementptr inbounds nuw { i32, i32 }, ptr %b.var, i32 0, i32 1, !dbg !23
diff --git a/toolchain/lower/testdata/operators/overloaded.carbon b/toolchain/lower/testdata/operators/overloaded.carbon
index d9919ae0aa78..2470c6ac4616 100644
--- a/toolchain/lower/testdata/operators/overloaded.carbon
+++ b/toolchain/lower/testdata/operators/overloaded.carbon
@@ -94,7 +94,7 @@ fn Calculate(a: Number, b: Number) -> Number {
 // CHECK:STDOUT: ; Function Attrs: nounwind
 // CHECK:STDOUT: define void @_CCalculate.Main(ptr sret({ i1 }) %return, ptr %a, ptr %b) #0 !dbg !29 {
 // CHECK:STDOUT: entry:
-// CHECK:STDOUT:   %.loc30_10.1.temp = alloca { i1 }, align 8, !dbg !33
+// CHECK:STDOUT:   %.loc30_10.1.temp = alloca { i1 }, align 1, !dbg !33
 // CHECK:STDOUT:   call void @llvm.lifetime.start.p0(ptr %.loc30_10.1.temp), !dbg !33
 // CHECK:STDOUT:   call void @"_COp.Number.Main:Negate.Core"(ptr %.loc30_10.1.temp, ptr %a), !dbg !33
 // CHECK:STDOUT:   call void @"_COp.Number.Main:MulWith.3dbfed2bcb44ac1d.Core"(ptr %return, ptr %.loc30_10.1.temp, ptr %b), !dbg !33
diff --git a/toolchain/lower/testdata/packages/imported_type_completeness.carbon b/toolchain/lower/testdata/packages/imported_type_completeness.carbon
index 3f8f17bded09..31b52753fb48 100644
--- a/toolchain/lower/testdata/packages/imported_type_completeness.carbon
+++ b/toolchain/lower/testdata/packages/imported_type_completeness.carbon
@@ -122,8 +122,8 @@ fn CallF() {
 // CHECK:STDOUT:
 // CHECK:STDOUT: ; Function Attrs: nounwind
 // CHECK:STDOUT: define linkonce_odr void @_CG.Main.e43630e9a6c38c3f() #0 !dbg !17 {
-// CHECK:STDOUT:   %temp = alloca {}, align 8, !dbg !18
-// CHECK:STDOUT:   %temp1 = alloca {}, align 8, !dbg !19
+// CHECK:STDOUT:   %temp = alloca {}, align 1, !dbg !18
+// CHECK:STDOUT:   %temp1 = alloca {}, align 1, !dbg !19
 // CHECK:STDOUT:   call void @llvm.lifetime.start.p0(ptr %temp), !dbg !18
 // CHECK:STDOUT:   %1 = call i123 @_CF.C.Main.e43630e9a6c38c3f(), !dbg !20
 // CHECK:STDOUT:   call void @llvm.lifetime.start.p0(ptr %temp1), !dbg !19
@@ -267,7 +267,7 @@ fn CallF() {
 // CHECK:STDOUT: ; Function Attrs: nounwind
 // CHECK:STDOUT: define void @_CCallF.Main() #0 !dbg !4 {
 // CHECK:STDOUT: entry:
-// CHECK:STDOUT:   %.loc9_9.2.temp = alloca {}, align 8, !dbg !7
+// CHECK:STDOUT:   %.loc9_9.2.temp = alloca {}, align 1, !dbg !7
 // CHECK:STDOUT:   call void @llvm.lifetime.start.p0(ptr %.loc9_9.2.temp), !dbg !7
 // CHECK:STDOUT:   call void @_CF.Main.48caacd0cd7b6e0f(ptr @C.val.a51.loc9_11.3), !dbg !8
 // CHECK:STDOUT:   call void @"_COp.a2f46f9b7e36af17:core.Destroy.Core"(ptr @C.val.a51), !dbg !7
diff --git a/toolchain/lower/testdata/pointer/address_of_field.carbon b/toolchain/lower/testdata/pointer/address_of_field.carbon
index 6876f19d342b..6a8f6e0d72e6 100644
--- a/toolchain/lower/testdata/pointer/address_of_field.carbon
+++ b/toolchain/lower/testdata/pointer/address_of_field.carbon
@@ -27,7 +27,7 @@ fn F() {
 // CHECK:STDOUT: ; Function Attrs: nounwind
 // CHECK:STDOUT: define void @_CF.Main() #0 !dbg !4 {
 // CHECK:STDOUT: entry:
-// CHECK:STDOUT:   %s.var = alloca { i32, i32 }, align 8, !dbg !7
+// CHECK:STDOUT:   %s.var = alloca { i32, i32 }, align 4, !dbg !7
 // CHECK:STDOUT:   call void @llvm.lifetime.start.p0(ptr %s.var), !dbg !7
 // CHECK:STDOUT:   %.loc16_46.3.a = getelementptr inbounds nuw { i32, i32 }, ptr %s.var, i32 0, i32 0, !dbg !8
 // CHECK:STDOUT:   %.loc16_46.6.b = getelementptr inbounds nuw { i32, i32 }, ptr %s.var, i32 0, i32 1, !dbg !8
diff --git a/toolchain/lower/testdata/primitives/optional.carbon b/toolchain/lower/testdata/primitives/optional.carbon
index 72ec4dcbacc9..5168ed3d31b0 100644
--- a/toolchain/lower/testdata/primitives/optional.carbon
+++ b/toolchain/lower/testdata/primitives/optional.carbon
@@ -86,14 +86,14 @@ fn F(c: Core.Optional(C*)) -> Core.Optional(C*) {
 // CHECK:STDOUT: ; Function Attrs: nounwind
 // CHECK:STDOUT: define void @_CAddOrRemoveConst.Main(i32 %a, i32 %b) #0 !dbg !24 {
 // CHECK:STDOUT: entry:
-// CHECK:STDOUT:   %_.var.loc11 = alloca <{ i32, i1 }>, align 8, !dbg !30
-// CHECK:STDOUT:   %_.var.loc12 = alloca <{ i32, i1 }>, align 8, !dbg !31
-// CHECK:STDOUT:   %_.var.loc13 = alloca <{ i32, i1 }>, align 8, !dbg !32
-// CHECK:STDOUT:   %_.var.loc14 = alloca <{ i32, i1 }>, align 8, !dbg !33
-// CHECK:STDOUT:   %_.var.loc15 = alloca <{ i32, i1 }>, align 8, !dbg !34
-// CHECK:STDOUT:   %_.var.loc16 = alloca <{ i32, i1 }>, align 8, !dbg !35
-// CHECK:STDOUT:   %_.var.loc17 = alloca <{ i32, i1 }>, align 8, !dbg !36
-// CHECK:STDOUT:   %_.var.loc18 = alloca <{ i32, i1 }>, align 8, !dbg !37
+// CHECK:STDOUT:   %_.var.loc11 = alloca <{ i32, i1 }>, align 4, !dbg !30
+// CHECK:STDOUT:   %_.var.loc12 = alloca <{ i32, i1 }>, align 4, !dbg !31
+// CHECK:STDOUT:   %_.var.loc13 = alloca <{ i32, i1 }>, align 4, !dbg !32
+// CHECK:STDOUT:   %_.var.loc14 = alloca <{ i32, i1 }>, align 4, !dbg !33
+// CHECK:STDOUT:   %_.var.loc15 = alloca <{ i32, i1 }>, align 4, !dbg !34
+// CHECK:STDOUT:   %_.var.loc16 = alloca <{ i32, i1 }>, align 4, !dbg !35
+// CHECK:STDOUT:   %_.var.loc17 = alloca <{ i32, i1 }>, align 4, !dbg !36
+// CHECK:STDOUT:   %_.var.loc18 = alloca <{ i32, i1 }>, align 4, !dbg !37
 // CHECK:STDOUT:   call void @llvm.lifetime.start.p0(ptr %_.var.loc11), !dbg !30
 // CHECK:STDOUT:   call void @"_CConvert.6391a65a70757668:ImplicitAs.116c0b3f4fb552e2.Core.406c55ecaefc4691"(ptr %_.var.loc11, i32 %a), !dbg !30
 // CHECK:STDOUT:   call void @llvm.lifetime.start.p0(ptr %_.var.loc12), !dbg !31
diff --git a/toolchain/lower/testdata/struct/empty.carbon b/toolchain/lower/testdata/struct/empty.carbon
index 879a31c8daa7..9b0e85cc47c8 100644
--- a/toolchain/lower/testdata/struct/empty.carbon
+++ b/toolchain/lower/testdata/struct/empty.carbon
@@ -22,8 +22,8 @@ fn Run() -> i32 {
 // CHECK:STDOUT: ; Function Attrs: nounwind
 // CHECK:STDOUT: define i32 @main() #0 !dbg !4 {
 // CHECK:STDOUT: entry:
-// CHECK:STDOUT:   %x.var = alloca {}, align 8, !dbg !8
-// CHECK:STDOUT:   %_.var = alloca {}, align 8, !dbg !9
+// CHECK:STDOUT:   %x.var = alloca {}, align 1, !dbg !8
+// CHECK:STDOUT:   %_.var = alloca {}, align 1, !dbg !9
 // CHECK:STDOUT:   call void @llvm.lifetime.start.p0(ptr %x.var), !dbg !8
 // CHECK:STDOUT:   call void @llvm.lifetime.start.p0(ptr %_.var), !dbg !9
 // CHECK:STDOUT:   ret i32 0, !dbg !10
diff --git a/toolchain/lower/testdata/struct/layout.carbon b/toolchain/lower/testdata/struct/layout.carbon
index 519df79d392e..690825be9c4c 100644
--- a/toolchain/lower/testdata/struct/layout.carbon
+++ b/toolchain/lower/testdata/struct/layout.carbon
@@ -81,7 +81,7 @@ fn F() {
 // CHECK:STDOUT: ; Function Attrs: nounwind
 // CHECK:STDOUT: define void @_CF.Main() #0 !dbg !4 {
 // CHECK:STDOUT: entry:
-// CHECK:STDOUT:   %no_padding.var = alloca { i32, i32, i32 }, align 8, !dbg !7
+// CHECK:STDOUT:   %no_padding.var = alloca { i32, i32, i32 }, align 4, !dbg !7
 // CHECK:STDOUT:   call void @llvm.lifetime.start.p0(ptr %no_padding.var), !dbg !7
 // CHECK:STDOUT:   %.loc8.x = getelementptr inbounds nuw { i32, i32, i32 }, ptr %no_padding.var, i32 0, i32 0, !dbg !8
 // CHECK:STDOUT:   call void @_CG.Main(ptr %.loc8.x), !dbg !9
diff --git a/toolchain/lower/testdata/struct/member_access.carbon b/toolchain/lower/testdata/struct/member_access.carbon
index 05e06a9a886f..a8449f6838d9 100644
--- a/toolchain/lower/testdata/struct/member_access.carbon
+++ b/toolchain/lower/testdata/struct/member_access.carbon
@@ -31,7 +31,7 @@ fn Run() -> i32 {
 // CHECK:STDOUT:   call void @llvm.lifetime.start.p0(ptr %x.var), !dbg !8
 // CHECK:STDOUT:   %.loc14_48.3.a = getelementptr inbounds nuw <{ double, i32 }>, ptr %x.var, i32 0, i32 0, !dbg !11
 // CHECK:STDOUT:   %.loc14_48.6.b = getelementptr inbounds nuw <{ double, i32 }>, ptr %x.var, i32 0, i32 1, !dbg !11
-// CHECK:STDOUT:   call void @llvm.memcpy.p0.p0.i64(ptr align 1 %x.var, ptr align 1 @struct.084.loc14_3, i64 12, i1 false), !dbg !8
+// CHECK:STDOUT:   call void @llvm.memcpy.p0.p0.i64(ptr align 8 %x.var, ptr align 8 @struct.084.loc14_3, i64 12, i1 false), !dbg !8
 // CHECK:STDOUT:   call void @llvm.lifetime.start.p0(ptr %y.var), !dbg !9
 // CHECK:STDOUT:   %.loc15_17.1.b = getelementptr inbounds nuw <{ double, i32 }>, ptr %x.var, i32 0, i32 1, !dbg !12
 // CHECK:STDOUT:   %.loc15_17.2 = load i32, ptr %.loc15_17.1.b, align 4, !dbg !12
diff --git a/toolchain/lower/testdata/struct/nested_struct_in_place.carbon b/toolchain/lower/testdata/struct/nested_struct_in_place.carbon
index 01a190fe6541..5efbcdcc2039 100644
--- a/toolchain/lower/testdata/struct/nested_struct_in_place.carbon
+++ b/toolchain/lower/testdata/struct/nested_struct_in_place.carbon
@@ -24,7 +24,7 @@ fn G() {
 // CHECK:STDOUT: ; Function Attrs: nounwind
 // CHECK:STDOUT: define void @_CG.Main() #0 !dbg !4 {
 // CHECK:STDOUT: entry:
-// CHECK:STDOUT:   %_.var = alloca { { i32, i32, i32 }, { i32, i32, i32 } }, align 8, !dbg !7
+// CHECK:STDOUT:   %_.var = alloca { { i32, i32, i32 }, { i32, i32, i32 } }, align 4, !dbg !7
 // CHECK:STDOUT:   call void @llvm.lifetime.start.p0(ptr %_.var), !dbg !7
 // CHECK:STDOUT:   %.loc16_74.1.a = getelementptr inbounds nuw { { i32, i32, i32 }, { i32, i32, i32 } }, ptr %_.var, i32 0, i32 0, !dbg !8
 // CHECK:STDOUT:   call void @_CF.Main(ptr %.loc16_74.1.a), !dbg !9
diff --git a/toolchain/lower/testdata/struct/one_entry.carbon b/toolchain/lower/testdata/struct/one_entry.carbon
index e66fe8cafd3f..344373c97449 100644
--- a/toolchain/lower/testdata/struct/one_entry.carbon
+++ b/toolchain/lower/testdata/struct/one_entry.carbon
@@ -22,8 +22,8 @@ fn Run() -> i32 {
 // CHECK:STDOUT: ; Function Attrs: nounwind
 // CHECK:STDOUT: define i32 @main() #0 !dbg !4 {
 // CHECK:STDOUT: entry:
-// CHECK:STDOUT:   %x.var = alloca { i32 }, align 8, !dbg !8
-// CHECK:STDOUT:   %_.var = alloca { i32 }, align 8, !dbg !9
+// CHECK:STDOUT:   %x.var = alloca { i32 }, align 4, !dbg !8
+// CHECK:STDOUT:   %_.var = alloca { i32 }, align 4, !dbg !9
 // CHECK:STDOUT:   call void @llvm.lifetime.start.p0(ptr %x.var), !dbg !8
 // CHECK:STDOUT:   store { i32 } { i32 4 }, ptr %x.var, align 4, !dbg !8
 // CHECK:STDOUT:   call void @llvm.lifetime.start.p0(ptr %_.var), !dbg !9
diff --git a/toolchain/lower/testdata/struct/two_entries.carbon b/toolchain/lower/testdata/struct/two_entries.carbon
index 94fdcb05a6c3..1a5cc6708fa1 100644
--- a/toolchain/lower/testdata/struct/two_entries.carbon
+++ b/toolchain/lower/testdata/struct/two_entries.carbon
@@ -24,8 +24,8 @@ fn Run() -> i32 {
 // CHECK:STDOUT: ; Function Attrs: nounwind
 // CHECK:STDOUT: define i32 @main() #0 !dbg !4 {
 // CHECK:STDOUT: entry:
-// CHECK:STDOUT:   %x.var = alloca { i32, i32 }, align 8, !dbg !8
-// CHECK:STDOUT:   %_.var = alloca { i32, i32 }, align 8, !dbg !9
+// CHECK:STDOUT:   %x.var = alloca { i32, i32 }, align 4, !dbg !8
+// CHECK:STDOUT:   %_.var = alloca { i32, i32 }, align 4, !dbg !9
 // CHECK:STDOUT:   call void @llvm.lifetime.start.p0(ptr %x.var), !dbg !8
 // CHECK:STDOUT:   %.loc14_46.3.a = getelementptr inbounds nuw { i32, i32 }, ptr %x.var, i32 0, i32 0, !dbg !10
 // CHECK:STDOUT:   %.loc14_46.6.b = getelementptr inbounds nuw { i32, i32 }, ptr %x.var, i32 0, i32 1, !dbg !10
diff --git a/toolchain/lower/testdata/tuple/access/element_access.carbon b/toolchain/lower/testdata/tuple/access/element_access.carbon
index ab2faa7cc45c..11c3a3977615 100644
--- a/toolchain/lower/testdata/tuple/access/element_access.carbon
+++ b/toolchain/lower/testdata/tuple/access/element_access.carbon
@@ -25,7 +25,7 @@ fn Run() -> i32 {
 // CHECK:STDOUT: ; Function Attrs: nounwind
 // CHECK:STDOUT: define i32 @main() #0 !dbg !4 {
 // CHECK:STDOUT: entry:
-// CHECK:STDOUT:   %a.var = alloca { i32, i32, i32 }, align 8, !dbg !8
+// CHECK:STDOUT:   %a.var = alloca { i32, i32, i32 }, align 4, !dbg !8
 // CHECK:STDOUT:   %_.var.loc15 = alloca i32, align 4, !dbg !9
 // CHECK:STDOUT:   %_.var.loc16 = alloca i32, align 4, !dbg !10
 // CHECK:STDOUT:   call void @llvm.lifetime.start.p0(ptr %a.var), !dbg !8
diff --git a/toolchain/lower/testdata/tuple/access/return_value_access.carbon b/toolchain/lower/testdata/tuple/access/return_value_access.carbon
index 813f2ff824af..0cab69b6c67a 100644
--- a/toolchain/lower/testdata/tuple/access/return_value_access.carbon
+++ b/toolchain/lower/testdata/tuple/access/return_value_access.carbon
@@ -34,7 +34,7 @@ fn Run() {
 // CHECK:STDOUT: define i32 @main() #0 !dbg !10 {
 // CHECK:STDOUT: entry:
 // CHECK:STDOUT:   %_.var = alloca i32, align 4, !dbg !14
-// CHECK:STDOUT:   %.loc16_18.1.temp = alloca { i32, i32 }, align 8, !dbg !15
+// CHECK:STDOUT:   %.loc16_18.1.temp = alloca { i32, i32 }, align 4, !dbg !15
 // CHECK:STDOUT:   call void @llvm.lifetime.start.p0(ptr %_.var), !dbg !14
 // CHECK:STDOUT:   call void @llvm.lifetime.start.p0(ptr %.loc16_18.1.temp), !dbg !15
 // CHECK:STDOUT:   call void @_CF.Main(ptr %.loc16_18.1.temp), !dbg !15
diff --git a/toolchain/lower/testdata/tuple/empty.carbon b/toolchain/lower/testdata/tuple/empty.carbon
index 63dc8db0903d..ad44c7bf7206 100644
--- a/toolchain/lower/testdata/tuple/empty.carbon
+++ b/toolchain/lower/testdata/tuple/empty.carbon
@@ -22,8 +22,8 @@ fn Run() -> i32 {
 // CHECK:STDOUT: ; Function Attrs: nounwind
 // CHECK:STDOUT: define i32 @main() #0 !dbg !4 {
 // CHECK:STDOUT: entry:
-// CHECK:STDOUT:   %x.var = alloca {}, align 8, !dbg !8
-// CHECK:STDOUT:   %_.var = alloca {}, align 8, !dbg !9
+// CHECK:STDOUT:   %x.var = alloca {}, align 1, !dbg !8
+// CHECK:STDOUT:   %_.var = alloca {}, align 1, !dbg !9
 // CHECK:STDOUT:   call void @llvm.lifetime.start.p0(ptr %x.var), !dbg !8
 // CHECK:STDOUT:   call void @llvm.lifetime.start.p0(ptr %_.var), !dbg !9
 // CHECK:STDOUT:   ret i32 0, !dbg !10
diff --git a/toolchain/lower/testdata/tuple/nested_tuple_in_place.carbon b/toolchain/lower/testdata/tuple/nested_tuple_in_place.carbon
index c98e04654b13..aabff3aa9112 100644
--- a/toolchain/lower/testdata/tuple/nested_tuple_in_place.carbon
+++ b/toolchain/lower/testdata/tuple/nested_tuple_in_place.carbon
@@ -24,7 +24,7 @@ fn G() {
 // CHECK:STDOUT: ; Function Attrs: nounwind
 // CHECK:STDOUT: define void @_CG.Main() #0 !dbg !4 {
 // CHECK:STDOUT: entry:
-// CHECK:STDOUT:   %_.var = alloca { { i32, i32, i32 }, { i32, i32, i32 } }, align 8, !dbg !7
+// CHECK:STDOUT:   %_.var = alloca { { i32, i32, i32 }, { i32, i32, i32 } }, align 4, !dbg !7
 // CHECK:STDOUT:   call void @llvm.lifetime.start.p0(ptr %_.var), !dbg !7
 // CHECK:STDOUT:   %tuple.elem0.tuple.elem = getelementptr inbounds nuw { { i32, i32, i32 }, { i32, i32, i32 } }, ptr %_.var, i32 0, i32 0, !dbg !8
 // CHECK:STDOUT:   call void @_CF.Main(ptr %tuple.elem0.tuple.elem), !dbg !9
diff --git a/toolchain/lower/testdata/tuple/one_entry.carbon b/toolchain/lower/testdata/tuple/one_entry.carbon
index aeada9660703..2bf8397cc9f1 100644
--- a/toolchain/lower/testdata/tuple/one_entry.carbon
+++ b/toolchain/lower/testdata/tuple/one_entry.carbon
@@ -22,8 +22,8 @@ fn Run() -> i32 {
 // CHECK:STDOUT: ; Function Attrs: nounwind
 // CHECK:STDOUT: define i32 @main() #0 !dbg !4 {
 // CHECK:STDOUT: entry:
-// CHECK:STDOUT:   %x.var = alloca { i32 }, align 8, !dbg !8
-// CHECK:STDOUT:   %_.var = alloca { i32 }, align 8, !dbg !9
+// CHECK:STDOUT:   %x.var = alloca { i32 }, align 4, !dbg !8
+// CHECK:STDOUT:   %_.var = alloca { i32 }, align 4, !dbg !9
 // CHECK:STDOUT:   call void @llvm.lifetime.start.p0(ptr %x.var), !dbg !8
 // CHECK:STDOUT:   store { i32 } { i32 1 }, ptr %x.var, align 4, !dbg !8
 // CHECK:STDOUT:   call void @llvm.lifetime.start.p0(ptr %_.var), !dbg !9
diff --git a/toolchain/lower/testdata/tuple/two_entries.carbon b/toolchain/lower/testdata/tuple/two_entries.carbon
index a0ec9aa74ce0..08f518f223fb 100644
--- a/toolchain/lower/testdata/tuple/two_entries.carbon
+++ b/toolchain/lower/testdata/tuple/two_entries.carbon
@@ -24,8 +24,8 @@ fn Run() -> i32 {
 // CHECK:STDOUT: ; Function Attrs: nounwind
 // CHECK:STDOUT: define i32 @main() #0 !dbg !4 {
 // CHECK:STDOUT: entry:
-// CHECK:STDOUT:   %x.var = alloca { i32, i32 }, align 8, !dbg !8
-// CHECK:STDOUT:   %_.var = alloca { i32, i32 }, align 8, !dbg !9
+// CHECK:STDOUT:   %x.var = alloca { i32, i32 }, align 4, !dbg !8
+// CHECK:STDOUT:   %_.var = alloca { i32, i32 }, align 4, !dbg !9
 // CHECK:STDOUT:   call void @llvm.lifetime.start.p0(ptr %x.var), !dbg !8
 // CHECK:STDOUT:   %tuple.elem0.loc14.tuple.elem = getelementptr inbounds nuw { i32, i32 }, ptr %x.var, i32 0, i32 0, !dbg !10
 // CHECK:STDOUT:   %tuple.elem1.loc14.tuple.elem = getelementptr inbounds nuw { i32, i32 }, ptr %x.var, i32 0, i32 1, !dbg !10
diff --git a/toolchain/lower/testdata/tuple/value_formation.carbon b/toolchain/lower/testdata/tuple/value_formation.carbon
index 9b29aa98bbdc..997776e1ad9d 100644
--- a/toolchain/lower/testdata/tuple/value_formation.carbon
+++ b/toolchain/lower/testdata/tuple/value_formation.carbon
@@ -26,8 +26,11 @@ fn F() {
 // CHECK:STDOUT: ; Function Attrs: nounwind
 // CHECK:STDOUT: define void @_CF.Main() #0 !dbg !4 {
 // CHECK:STDOUT: entry:
-// CHECK:STDOUT:   %a.var = alloca { i32, i32, i32 }, align 8, !dbg !7
-// CHECK:STDOUT:   %b.var = alloca { i32, i32, i32 }, align 8, !dbg !8
+// CHECK:STDOUT:   %a.var = alloca { i32, i32, i32 }, align 4, !dbg !7
+// CHECK:STDOUT:   %b.var = alloca { i32, i32, i32 }, align 4, !dbg !8
+// CHECK:STDOUT:   %tuple.loc18_6 = alloca { i32, i32, i32 }, align 4, !dbg !9
+// CHECK:STDOUT:   %tuple.loc18_9 = alloca { i32, i32, i32 }, align 4, !dbg !10
+// CHECK:STDOUT:   %tuple.loc18_10 = alloca { ptr, ptr }, align 8, !dbg !11
 // CHECK:STDOUT:   call void @llvm.lifetime.start.p0(ptr %a.var), !dbg !7
 // CHECK:STDOUT:   call void @llvm.lifetime.start.p0(ptr %b.var), !dbg !8
 // CHECK:STDOUT:   %tuple.elem0.loc18_6.tuple.elem = getelementptr inbounds nuw { i32, i32, i32 }, ptr %a.var, i32 0, i32 0, !dbg !9
@@ -36,7 +39,7 @@ fn F() {
 // CHECK:STDOUT:   %.loc18_6.2 = load i32, ptr %tuple.elem1.loc18_6.tuple.elem, align 4, !dbg !9
 // CHECK:STDOUT:   %tuple.elem2.loc18_6.tuple.elem = getelementptr inbounds nuw { i32, i32, i32 }, ptr %a.var, i32 0, i32 2, !dbg !9
 // CHECK:STDOUT:   %.loc18_6.3 = load i32, ptr %tuple.elem2.loc18_6.tuple.elem, align 4, !dbg !9
-// CHECK:STDOUT:   %tuple.loc18_6 = alloca { i32, i32, i32 }, align 8, !dbg !9
+// CHECK:STDOUT:   call void @llvm.lifetime.start.p0(ptr %tuple.loc18_6), !dbg !9
 // CHECK:STDOUT:   %tuple.loc18_61 = getelementptr inbounds nuw { i32, i32, i32 }, ptr %tuple.loc18_6, i32 0, i32 0, !dbg !9
 // CHECK:STDOUT:   store i32 %.loc18_6.1, ptr %tuple.loc18_61, align 4, !dbg !9
 // CHECK:STDOUT:   %tuple.loc18_62 = getelementptr inbounds nuw { i32, i32, i32 }, ptr %tuple.loc18_6, i32 0, i32 1, !dbg !9
@@ -49,14 +52,14 @@ fn F() {
 // CHECK:STDOUT:   %.loc18_9.2 = load i32, ptr %tuple.elem1.loc18_9.tuple.elem, align 4, !dbg !10
 // CHECK:STDOUT:   %tuple.elem2.loc18_9.tuple.elem = getelementptr inbounds nuw { i32, i32, i32 }, ptr %b.var, i32 0, i32 2, !dbg !10
 // CHECK:STDOUT:   %.loc18_9.3 = load i32, ptr %tuple.elem2.loc18_9.tuple.elem, align 4, !dbg !10
-// CHECK:STDOUT:   %tuple.loc18_9 = alloca { i32, i32, i32 }, align 8, !dbg !10
+// CHECK:STDOUT:   call void @llvm.lifetime.start.p0(ptr %tuple.loc18_9), !dbg !10
 // CHECK:STDOUT:   %tuple.loc18_94 = getelementptr inbounds nuw { i32, i32, i32 }, ptr %tuple.loc18_9, i32 0, i32 0, !dbg !10
 // CHECK:STDOUT:   store i32 %.loc18_9.1, ptr %tuple.loc18_94, align 4, !dbg !10
 // CHECK:STDOUT:   %tuple.loc18_95 = getelementptr inbounds nuw { i32, i32, i32 }, ptr %tuple.loc18_9, i32 0, i32 1, !dbg !10
 // CHECK:STDOUT:   store i32 %.loc18_9.2, ptr %tuple.loc18_95, align 4, !dbg !10
 // CHECK:STDOUT:   %tuple.loc18_96 = getelementptr inbounds nuw { i32, i32, i32 }, ptr %tuple.loc18_9, i32 0, i32 2, !dbg !10
 // CHECK:STDOUT:   store i32 %.loc18_9.3, ptr %tuple.loc18_96, align 4, !dbg !10
-// CHECK:STDOUT:   %tuple.loc18_10 = alloca { ptr, ptr }, align 8, !dbg !11
+// CHECK:STDOUT:   call void @llvm.lifetime.start.p0(ptr %tuple.loc18_10), !dbg !11
 // CHECK:STDOUT:   %tuple.loc18_107 = getelementptr inbounds nuw { ptr, ptr }, ptr %tuple.loc18_10, i32 0, i32 0, !dbg !11
 // CHECK:STDOUT:   store ptr %tuple.loc18_6, ptr %tuple.loc18_107, align 8, !dbg !11
 // CHECK:STDOUT:   %tuple.loc18_108 = getelementptr inbounds nuw { ptr, ptr }, ptr %tuple.loc18_10, i32 0, i32 1, !dbg !11
@@ -84,7 +87,7 @@ fn F() {
 // CHECK:STDOUT:
 // CHECK:STDOUT: ; uselistorder directives
 // CHECK:STDOUT: uselistorder ptr @"_COp.9eed32d146d768a4:core.Destroy.Core", { 1, 0 }
-// CHECK:STDOUT: uselistorder ptr @llvm.lifetime.start.p0, { 1, 0 }
+// CHECK:STDOUT: uselistorder ptr @llvm.lifetime.start.p0, { 4, 3, 2, 1, 0 }
 // CHECK:STDOUT:
 // CHECK:STDOUT: attributes #0 = { nounwind }
 // CHECK:STDOUT: attributes #1 = { nocallback nofree nosync nounwind willreturn memory(argmem: readwrite) }
diff --git a/toolchain/lower/testdata/tuple/value_forwarding.carbon b/toolchain/lower/testdata/tuple/value_forwarding.carbon
index 2b90d533bd51..d4bab89ab3f0 100644
--- a/toolchain/lower/testdata/tuple/value_forwarding.carbon
+++ b/toolchain/lower/testdata/tuple/value_forwarding.carbon
@@ -25,6 +25,7 @@ fn F(a: (i32, i32, i32), b: (i32, i32, i32)) {
 // CHECK:STDOUT: define void @_CF.Main(ptr %a, ptr %b) #0 !dbg !4 {
 // CHECK:STDOUT: entry:
 // CHECK:STDOUT:   %tuple = alloca { ptr, ptr }, align 8, !dbg !11
+// CHECK:STDOUT:   call void @llvm.lifetime.start.p0(ptr %tuple), !dbg !11
 // CHECK:STDOUT:   %tuple1 = getelementptr inbounds nuw { ptr, ptr }, ptr %tuple, i32 0, i32 0, !dbg !11
 // CHECK:STDOUT:   store ptr %a, ptr %tuple1, align 8, !dbg !11
 // CHECK:STDOUT:   %tuple2 = getelementptr inbounds nuw { ptr, ptr }, ptr %tuple, i32 0, i32 1, !dbg !11
@@ -33,7 +34,11 @@ fn F(a: (i32, i32, i32), b: (i32, i32, i32)) {
 // CHECK:STDOUT:   ret void, !dbg !13
 // CHECK:STDOUT: }
 // CHECK:STDOUT:
+// CHECK:STDOUT: ; Function Attrs: nocallback nofree nosync nounwind willreturn memory(argmem: readwrite)
+// CHECK:STDOUT: declare void @llvm.lifetime.start.p0(ptr captures(none)) #1
+// CHECK:STDOUT:
 // CHECK:STDOUT: attributes #0 = { nounwind }
+// CHECK:STDOUT: attributes #1 = { nocallback nofree nosync nounwind willreturn memory(argmem: readwrite) }
 // CHECK:STDOUT:
 // CHECK:STDOUT: !llvm.module.flags = !{!0, !1}
 // CHECK:STDOUT: !llvm.dbg.cu = !{!2}
diff --git a/toolchain/lower/testdata/var/local.carbon b/toolchain/lower/testdata/var/local.carbon
index c9cfd620e711..28d42f0cf191 100644
--- a/toolchain/lower/testdata/var/local.carbon
+++ b/toolchain/lower/testdata/var/local.carbon
@@ -94,7 +94,7 @@ fn G() -> (i32, i32, i32) {
 // CHECK:STDOUT: ; Function Attrs: nounwind
 // CHECK:STDOUT: define void @_CG.Main(ptr sret({ i32, i32, i32 }) %return) #0 !dbg !10 {
 // CHECK:STDOUT: entry:
-// CHECK:STDOUT:   %a.var = alloca { i32, i32, i32 }, align 8, !dbg !11
+// CHECK:STDOUT:   %a.var = alloca { i32, i32, i32 }, align 4, !dbg !11
 // CHECK:STDOUT:   call void @llvm.lifetime.start.p0(ptr %a.var), !dbg !11
 // CHECK:STDOUT:   call void @llvm.memcpy.p0.p0.i64(ptr align 4 %a.var, ptr align 4 @tuple.8d2.loc4_50, i64 12, i1 false), !dbg !11
 // CHECK:STDOUT:   %tuple.elem0.loc8_10.1.tuple.elem = getelementptr inbounds nuw { i32, i32, i32 }, ptr %a.var, i32 0, i32 0, !dbg !12
diff --git a/toolchain/lower/testdata/var/param.carbon b/toolchain/lower/testdata/var/param.carbon
index 706904b1545c..0c992ee9398b 100644
--- a/toolchain/lower/testdata/var/param.carbon
+++ b/toolchain/lower/testdata/var/param.carbon
@@ -58,7 +58,7 @@ fn G() {
 // CHECK:STDOUT: ; Function Attrs: nounwind
 // CHECK:STDOUT: define void @_CG.Main() #0 !dbg !4 {
 // CHECK:STDOUT: entry:
-// CHECK:STDOUT:   %c.var = alloca {}, align 8, !dbg !7
+// CHECK:STDOUT:   %c.var = alloca {}, align 1, !dbg !7
 // CHECK:STDOUT:   call void @llvm.lifetime.start.p0(ptr %c.var), !dbg !7
 // CHECK:STDOUT:   call void @_CMake.C.Main(ptr %c.var), !dbg !8
 // CHECK:STDOUT:   call void @_CF.Main(ptr %c.var), !dbg !9
@@ -111,7 +111,7 @@ fn G() {
 // CHECK:STDOUT: ; Function Attrs: nounwind
 // CHECK:STDOUT: define void @_CG.Main() #0 !dbg !4 {
 // CHECK:STDOUT: entry:
-// CHECK:STDOUT:   %c.var = alloca {}, align 8, !dbg !7
+// CHECK:STDOUT:   %c.var = alloca {}, align 1, !dbg !7
 // CHECK:STDOUT:   call void @llvm.lifetime.start.p0(ptr %c.var), !dbg !7
 // CHECK:STDOUT:   call void @llvm.memcpy.p0.p0.i64(ptr align 1 %c.var, ptr align 1 @C.val.loc11, i64 0, i1 false), !dbg !7
 // CHECK:STDOUT:   call void @_CF.Main(ptr %c.var), !dbg !8
diff --git a/toolchain/lower/testdata/var/uninitialized.carbon b/toolchain/lower/testdata/var/uninitialized.carbon
index 355f894929d7..79271b4b4a39 100644
--- a/toolchain/lower/testdata/var/uninitialized.carbon
+++ b/toolchain/lower/testdata/var/uninitialized.carbon
@@ -27,8 +27,8 @@ fn Run() {
 // CHECK:STDOUT: entry:
 // CHECK:STDOUT:   %a.var = alloca i32, align 4, !dbg !8
 // CHECK:STDOUT:   %b.var = alloca double, align 8, !dbg !9
-// CHECK:STDOUT:   %c.var = alloca {}, align 8, !dbg !10
-// CHECK:STDOUT:   %d.var = alloca {}, align 8, !dbg !11
+// CHECK:STDOUT:   %c.var = alloca {}, align 1, !dbg !10
+// CHECK:STDOUT:   %d.var = alloca {}, align 1, !dbg !11
 // CHECK:STDOUT:   %e.var = alloca i1, align 1, !dbg !12
 // CHECK:STDOUT:   %f.var = alloca ptr, align 8, !dbg !13
 // CHECK:STDOUT:   call void @llvm.lifetime.start.p0(ptr %a.var), !dbg !8