Start doing more validation of intrinsics: assert, new, delete, rand (#2766)

This is adding more validation of intrinsics. It addresses a bug in rand where CHECK-fails would occur for bad range inputs, instead of a runtime error. I'm also addressing what I think was an int32 range issue in the handling by running the generator with int64.

explorer/interpreter/interpreter.cpp

@@ -7,6 +7,7 @@
 #include <llvm/Support/raw_ostream.h>
 
 #include <iterator>
+#include <limits>
 #include <map>
 #include <memory>
 #include <optional>
@@ -40,8 +41,6 @@ using llvm::isa;
 
 namespace Carbon {
 
-static std::mt19937 generator(12);
-
 // Constructs an ActionStack suitable for the specified phase.
 static auto MakeTodo(Phase phase, Nonnull<Heap*> heap) -> ActionStack {
   switch (phase) {
@@ -1593,12 +1592,24 @@ auto Interpreter::StepExp() -> ErrorOr<Success> {
         }
         case IntrinsicExpression::Intrinsic::Rand: {
           CARBON_CHECK(args.size() == 2);
-          const auto& low = cast<IntValue>(*args[0]).value();
-          const auto& high = cast<IntValue>(*args[1]).value();
-          CARBON_CHECK(high > low);
+          const int64_t low = cast<IntValue>(*args[0]).value();
+          const int64_t high = cast<IntValue>(*args[1]).value();
+          if (low >= high) {
+            return ProgramError(exp.source_loc())
+                   << "Rand inputs must be ordered for a non-empty range: "
+                   << low << " must be less than " << high;
+          }
+          // Use 64-bit to handle large ranges where `high - low` might exceed
+          // int32_t maximums.
+          static std::mt19937_64 generator(12);
+          const int64_t range = high - low;
           // We avoid using std::uniform_int_distribution because it's not
           // reproducible across builds/platforms.
-          int r = (generator() % (high - low)) + low;
+          int64_t r = (generator() % range) + low;
+          CARBON_CHECK(r >= std::numeric_limits<int32_t>::min() &&
+                       r <= std::numeric_limits<int32_t>::max())
+              << "Non-int32 result: " << r;
+          CARBON_CHECK(r >= low && r <= high) << "Out-of-range result: " << r;
           return todo_.FinishAction(arena_->New<IntValue>(r));
         }
         case IntrinsicExpression::Intrinsic::ImplicitAs: {

explorer/interpreter/type_checker.cpp

@@ -3666,7 +3666,7 @@ auto TypeChecker::TypeCheckExp(Nonnull<Expression*> e,
         case IntrinsicExpression::Intrinsic::Dealloc: {
           if (args.size() != 1) {
             return ProgramError(e->source_loc())
-                   << "__intrinsic_new takes 1 argument";
+                   << "__intrinsic_delete takes 1 argument";
           }
           const auto* arg_type = &args[0]->static_type();
           CARBON_RETURN_IF_ERROR(

explorer/testdata/assert/assert.carbon

@@ -0,0 +1,15 @@
+// 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
+//
+// AUTOUPDATE
+// RUN: %{explorer-run}
+// RUN: %{explorer-run-trace}
+// CHECK:STDOUT: result: 0
+
+package ExplorerTest api;
+
+fn Main() -> i32 {
+  Assert(true, "HALLO WELT");
+  return 0;
+}

explorer/testdata/assert/convert.carbon

@@ -0,0 +1,22 @@
+// 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
+//
+// AUTOUPDATE
+// RUN: %{explorer-run}
+// RUN: %{explorer-run-trace}
+// CHECK:STDOUT: result: 0
+
+package ExplorerTest api;
+
+class ConvertTo(T:! type) {
+  var v: T;
+  impl as ImplicitAs(T) {
+    fn Convert[self: Self]() -> T { return self.v; }
+  }
+}
+
+fn Main() -> i32 {
+  Assert({.v = true} as ConvertTo(bool), {.v = "Pass"} as ConvertTo(String));
+  return 0;
+}

explorer/testdata/assert/fail_assert.carbon

@@ -10,7 +10,6 @@
 package ExplorerTest api;
 
 fn Main() -> i32 {
-  Assert(true, "HALLO WELT");
   Assert(false, "HALLO WELT");
   return 0;
 }

explorer/testdata/assert/fail_convert.carbon

@@ -5,6 +5,7 @@
 // AUTOUPDATE
 // RUN: %{not} %{explorer-run}
 // RUN: %{not} %{explorer-run-trace}
+// CHECK:STDERR: RUNTIME ERROR: {{.*}}/explorer/data/prelude.carbon:{{.*}}: "Fail"
 
 package ExplorerTest api;
 
@@ -16,10 +17,6 @@ class ConvertTo(T:! type) {
 }
 
 fn Main() -> i32 {
-  // CHECK:STDERR: COMPILATION ERROR: {{.*}}/explorer/testdata/assert/fail_convert.carbon:[[@LINE+3]]: type error in __intrinsic_assert argument 0
-  // CHECK:STDERR: expected: bool
-  // CHECK:STDERR: actual: class ConvertTo(T = bool)
-  __intrinsic_assert({.v = true} as ConvertTo(bool), {.v = "Pass"} as ConvertTo(String));
-  __intrinsic_assert({.v = false} as ConvertTo(bool), {.v = "Fail"} as ConvertTo(String));
+  Assert({.v = false} as ConvertTo(bool), {.v = "Fail"} as ConvertTo(String));
   return 0;
 }

explorer/testdata/assert/fail_intrinsic_bool_type.carbon

@@ -0,0 +1,22 @@
+// 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
+//
+// AUTOUPDATE
+// RUN: %{not} %{explorer-run}
+// RUN: %{not} %{explorer-run-trace}
+
+package ExplorerTest api;
+
+class ConvertTo(T:! type) {
+  var v: T;
+  impl as ImplicitAs(T) {
+    fn Convert[self: Self]() -> T { return self.v; }
+  }
+}
+
+fn Main() -> i32 {
+  // CHECK:STDERR: SYNTAX ERROR: {{.*}}/explorer/testdata/assert/fail_intrinsic_bool_type.carbon:[[@LINE+1]]: syntax error, unexpected COMMA
+  __intrinsic_assert(, "unused");
+  return 0;
+}

explorer/testdata/assert/fail_intrinsic_no_args.carbon

@@ -0,0 +1,22 @@
+// 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
+//
+// AUTOUPDATE
+// RUN: %{not} %{explorer-run}
+// RUN: %{not} %{explorer-run-trace}
+
+package ExplorerTest api;
+
+class ConvertTo(T:! type) {
+  var v: T;
+  impl as ImplicitAs(T) {
+    fn Convert[self: Self]() -> T { return self.v; }
+  }
+}
+
+fn Main() -> i32 {
+  // CHECK:STDERR: COMPILATION ERROR: {{.*}}/explorer/testdata/assert/fail_intrinsic_no_args.carbon:[[@LINE+1]]: __intrinsic_assert takes 2 arguments
+  __intrinsic_assert();
+  return 0;
+}

explorer/testdata/assert/fail_intrinsic_no_convert.carbon

@@ -0,0 +1,24 @@
+// 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
+//
+// AUTOUPDATE
+// RUN: %{not} %{explorer-run}
+// RUN: %{not} %{explorer-run-trace}
+
+package ExplorerTest api;
+
+class ConvertTo(T:! type) {
+  var v: T;
+  impl as ImplicitAs(T) {
+    fn Convert[self: Self]() -> T { return self.v; }
+  }
+}
+
+fn Main() -> i32 {
+  // CHECK:STDERR: COMPILATION ERROR: {{.*}}/explorer/testdata/assert/fail_intrinsic_no_convert.carbon:[[@LINE+3]]: type error in __intrinsic_assert argument 0
+  // CHECK:STDERR: expected: bool
+  // CHECK:STDERR: actual: class ConvertTo(T = bool)
+  __intrinsic_assert({.v = true} as ConvertTo(bool), {.v = "Pass"} as ConvertTo(String));
+  return 0;
+}

explorer/testdata/assert/fail_intrinsic_str_type.carbon

@@ -0,0 +1,24 @@
+// 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
+//
+// AUTOUPDATE
+// RUN: %{not} %{explorer-run}
+// RUN: %{not} %{explorer-run-trace}
+
+package ExplorerTest api;
+
+class ConvertTo(T:! type) {
+  var v: T;
+  impl as ImplicitAs(T) {
+    fn Convert[self: Self]() -> T { return self.v; }
+  }
+}
+
+fn Main() -> i32 {
+  // CHECK:STDERR: COMPILATION ERROR: {{.*}}/explorer/testdata/assert/fail_intrinsic_str_type.carbon:[[@LINE+3]]: type error in __intrinsic_assert argument 1
+  // CHECK:STDERR: expected: String
+  // CHECK:STDERR: actual: i32
+  __intrinsic_assert(true, 1);
+  return 0;
+}

explorer/testdata/pointer/fail_delete_uninit.carbon

@@ -0,0 +1,16 @@
+// 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
+//
+// AUTOUPDATE
+// RUN: %{not} %{explorer-run}
+// RUN: %{not} %{explorer-run-trace}
+
+package ExplorerTest api;
+
+fn Main() -> i32 {
+  var p: i32*;
+  // CHECK:STDERR: RUNTIME ERROR: {{.*}}/explorer/testdata/pointer/fail_delete_uninit.carbon:[[@LINE+1]]: undefined behavior: access to uninitialized value Uninit<Placeholder<p>>
+  heap.Delete(p);
+  return 0;
+}

explorer/testdata/pointer/fail_intrinsic_delete_no_args.carbon

@@ -0,0 +1,15 @@
+// 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
+//
+// AUTOUPDATE
+// RUN: %{not} %{explorer-run}
+// RUN: %{not} %{explorer-run-trace}
+
+package ExplorerTest api;
+
+fn Main() -> i32 {
+  // CHECK:STDERR: COMPILATION ERROR: {{.*}}/explorer/testdata/pointer/fail_intrinsic_delete_no_args.carbon:[[@LINE+1]]: __intrinsic_delete takes 1 argument
+  __intrinsic_delete();
+  return 0;
+}

explorer/testdata/pointer/fail_intrinsic_delete_type.carbon

@@ -0,0 +1,18 @@
+// 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
+//
+// AUTOUPDATE
+// RUN: %{not} %{explorer-run}
+// RUN: %{not} %{explorer-run-trace}
+
+package ExplorerTest api;
+
+fn Main() -> i32 {
+  var x: i32;
+  // CHECK:STDERR: COMPILATION ERROR: {{.*}}/explorer/testdata/pointer/fail_intrinsic_delete_type.carbon:[[@LINE+3]]: type error in *
+  // CHECK:STDERR: expected a pointer type
+  // CHECK:STDERR: actual: i32
+  __intrinsic_delete(x);
+  return 0;
+}

explorer/testdata/pointer/fail_intrinsic_new_no_args.carbon

@@ -0,0 +1,15 @@
+// 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
+//
+// AUTOUPDATE
+// RUN: %{not} %{explorer-run}
+// RUN: %{not} %{explorer-run-trace}
+
+package ExplorerTest api;
+
+fn Main() -> i32 {
+  // CHECK:STDERR: COMPILATION ERROR: {{.*}}/explorer/testdata/pointer/fail_intrinsic_new_no_args.carbon:[[@LINE+1]]: __intrinsic_new takes 1 argument
+  __intrinsic_new();
+  return 0;
+}

explorer/testdata/pointer/new_and_delete_class.carbon

@@ -0,0 +1,23 @@
+// 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
+//
+// AUTOUPDATE
+// RUN: %{explorer-run}
+// RUN: %{explorer-run-trace}
+// CHECK:STDOUT: result: 0
+
+package ExplorerTest api;
+
+class C {
+  fn DoPrint() { Print("test"); }
+}
+
+fn Main() -> i32 {
+  var p: auto = heap.New(C);
+  var y: auto = *p;
+  // The following line would fail with: "could not find `y: auto`"
+  // y.DoPrint();
+  heap.Delete(p);
+  return 0;
+}

explorer/testdata/pointer/new_and_delete_fn.carbon

@@ -0,0 +1,21 @@
+// 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
+//
+// AUTOUPDATE
+// RUN: %{explorer-run}
+// RUN: %{explorer-run-trace}
+// CHECK:STDOUT: test
+// CHECK:STDOUT: result: 0
+
+package ExplorerTest api;
+
+fn F() { Print("test"); }
+
+fn Main() -> i32 {
+  var p: auto = heap.New(F);
+  var y: auto = *p;
+  y();
+  heap.Delete(p);
+  return 0;
+}

explorer/testdata/random/fail_empty_range.carbon

@@ -0,0 +1,15 @@
+// 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
+//
+// AUTOUPDATE
+// RUN: %{not} %{explorer-run}
+// RUN: %{not} %{explorer-run-trace}
+// CHECK:STDERR: RUNTIME ERROR: {{.*}}/explorer/data/prelude.carbon:{{.*}}: Rand inputs must be ordered for a non-empty range: 0 must be less than 0
+
+package ExplorerTest api;
+
+fn Main() -> i32 {
+  Rand(0, 0);
+  return 0;
+}

explorer/testdata/random/fail_intrinsic_no_args.carbon

@@ -0,0 +1,15 @@
+// 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
+//
+// AUTOUPDATE
+// RUN: %{not} %{explorer-run}
+// RUN: %{not} %{explorer-run-trace}
+
+package ExplorerTest api;
+
+fn Main() -> i32 {
+  // CHECK:STDERR: COMPILATION ERROR: {{.*}}/explorer/testdata/random/fail_intrinsic_no_args.carbon:[[@LINE+1]]: Rand takes 2 arguments, received 0
+  __intrinsic_rand();
+  return 0;
+}

explorer/testdata/random/fail_intrinsic_type0.carbon

@@ -0,0 +1,17 @@
+// 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
+//
+// AUTOUPDATE
+// RUN: %{not} %{explorer-run}
+// RUN: %{not} %{explorer-run-trace}
+
+package ExplorerTest api;
+
+fn Main() -> i32 {
+  // CHECK:STDERR: COMPILATION ERROR: {{.*}}/explorer/testdata/random/fail_intrinsic_type0.carbon:[[@LINE+3]]: type error in Rand argument 0
+  // CHECK:STDERR: expected: i32
+  // CHECK:STDERR: actual: String
+  __intrinsic_rand("a", 1);
+  return 0;
+}

explorer/testdata/random/fail_intrinsic_type1.carbon

@@ -0,0 +1,17 @@
+// 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
+//
+// AUTOUPDATE
+// RUN: %{not} %{explorer-run}
+// RUN: %{not} %{explorer-run-trace}
+
+package ExplorerTest api;
+
+fn Main() -> i32 {
+  // CHECK:STDERR: COMPILATION ERROR: {{.*}}/explorer/testdata/random/fail_intrinsic_type1.carbon:[[@LINE+3]]: type error in Rand argument 1
+  // CHECK:STDERR: expected: i32
+  // CHECK:STDERR: actual: String
+  __intrinsic_rand(1, "a");
+  return 0;
+}

explorer/testdata/random/fail_reverse_range.carbon

@@ -0,0 +1,15 @@
+// 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
+//
+// AUTOUPDATE
+// RUN: %{not} %{explorer-run}
+// RUN: %{not} %{explorer-run-trace}
+// CHECK:STDERR: RUNTIME ERROR: {{.*}}/explorer/data/prelude.carbon:{{.*}}: Rand inputs must be ordered for a non-empty range: 1 must be less than -1
+
+package ExplorerTest api;
+
+fn Main() -> i32 {
+  Rand(1, -1);
+  return 0;
+}

explorer/testdata/random/max_range.carbon

@@ -0,0 +1,19 @@
+// 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
+//
+// AUTOUPDATE
+// RUN: %{explorer-run}
+// RUN: %{explorer-run-trace}
+// CHECK:STDOUT: result: 0
+
+package ExplorerTest api;
+
+fn Main() -> i32 {
+  // -2147483648 is unsupported as a literal, but we can do it with a decrement.
+  var low: i32 = -2147483647;
+  low -= 1;
+  var high: i32 = 2147483647;
+  Rand(low, high);
+  return 0;
+}

explorer/testdata/random/random.carbon

@@ -9,15 +9,13 @@
 // CHECK:STDOUT: result: 0
 
 package ExplorerTest api;
-fn test(para: i32)->bool{
-  return true;
-}
+
 fn Main() -> i32 {
-  var i : i32 = Rand(0,100);
-  var j : i32 = Rand(0,100);
-  if(i == j){
+  var i: i32 = Rand(0, 100);
+  var j: i32 = Rand(0, 100);
+  if (i == j) {
     Print("HALLO WELT");
-  }else{
+  } else {
     Print("Nice!");
   }
   return 0;