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Switch CARBON_CHECK to a format string API (#4285)

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This switches `DCHECK` and `FATAL` as well.

The goal is to reduce the code size impact of these assertions so that
we can keep more of them enabled. Currently, the largest cost I see from
`CHECK` is not the actual check or the cold code itself, but actually
the failure to inline trivial functions due to the presence of the cold
code. This means that our goal isn't to reduce apparent code size in the
final binary but the LLVM IR cost assessed for these routines in the
inliner, which closely correlates with code size but is a bit different.

As discussed in #4283, experimentation shows that a single function call
with a minimal number of arguments is the lowest cost model for these.
This is easily achieved with a format-string API that internally uses
`llvm::formatv`. This PR is essentially the `CHECK` version of #4283.

However, the check macros are substantially harder to make work with
both format strings and streaming because they also take a condition.
Also, unexpectedly, I was very successful at devising a regular
expression based automated rewrite from the streaming to the format
string form with only low 10s of manual fixes. This includes compacting
strings broken up across lines, etc. Given how well that went, I've
prepared this PR which just directly switches to the format string API
and migrate everything to use it.

One nice side-effect is that the format string approach ends up greatly
simplifying the implementation here as well.

This is ... *shockingly* effective. Parsing speeds up by more than 3%
with just this change. And checking speeds up by **8%** with this change
alone:
```
BM_CompileAPIFileDenseDecls<Phase::Parse>/256      86.3µs ± 1%  82.9µs ± 1%  -3.94%  (p=0.000 n=17+19)
BM_CompileAPIFileDenseDecls<Phase::Parse>/1024      431µs ± 1%   415µs ± 1%  -3.76%  (p=0.000 n=18+19)
BM_CompileAPIFileDenseDecls<Phase::Parse>/4096     1.77ms ± 1%  1.71ms ± 1%  -3.18%  (p=0.000 n=18+19)
BM_CompileAPIFileDenseDecls<Phase::Parse>/16384    7.44ms ± 1%  7.17ms ± 2%  -3.56%  (p=0.000 n=18+20)
BM_CompileAPIFileDenseDecls<Phase::Parse>/65536    30.7ms ± 1%  29.7ms ± 1%  -3.15%  (p=0.000 n=18+20)
BM_CompileAPIFileDenseDecls<Phase::Parse>/262144    131ms ± 1%   127ms ± 1%  -2.81%  (p=0.000 n=18+18)
BM_CompileAPIFileDenseDecls<Phase::Check>/256       878µs ± 2%   800µs ± 1%  -8.91%  (p=0.000 n=19+20)
BM_CompileAPIFileDenseDecls<Phase::Check>/1024     1.88ms ± 2%  1.72ms ± 1%  -8.56%  (p=0.000 n=19+20)
BM_CompileAPIFileDenseDecls<Phase::Check>/4096     5.78ms ± 2%  5.28ms ± 1%  -8.70%  (p=0.000 n=20+18)
BM_CompileAPIFileDenseDecls<Phase::Check>/16384    21.9ms ± 1%  20.1ms ± 1%  -8.02%  (p=0.000 n=18+20)
BM_CompileAPIFileDenseDecls<Phase::Check>/65536    90.4ms ± 2%  83.1ms ± 1%  -8.04%  (p=0.000 n=19+20)
BM_CompileAPIFileDenseDecls<Phase::Check>/262144    381ms ± 2%   352ms ± 1%  -7.79%  (p=0.000 n=19+19)
```

---------

Co-authored-by: Richard Smith <richard@metafoo.co.uk>
Co-authored-by: josh11b <15258583+josh11b@users.noreply.github.com>
This commit is contained in:
Chandler Carruth
2024-09-12 16:42:08 +00:00
committed by GitHub
co-authored by Richard Smith josh11b
parent 35dfa5f03c
commit 4845f40dff
140 changed files with 1234 additions and 1161 deletions
Download Patch File Download Diff File Expand all files Collapse all files
toolchain/check/eval.cpp
+22 -21
View File
@@ -77,9 +77,10 @@ class EvalContext {
specifics().Get(specific_id_).generic_id &&
symbolic_info.index.region() == specific_eval_info_->region) {
auto inst_id = specific_eval_info_->values[symbolic_info.index.index()];
CARBON_CHECK(inst_id.is_valid())
<< "Forward reference in eval block: index "
<< symbolic_info.index.index() << " referenced before evaluation";
CARBON_CHECK(inst_id.is_valid(),
"Forward reference in eval block: index {0} referenced "
"before evaluation",
symbolic_info.index.index());
return constant_values().Get(inst_id);
}
}
@@ -464,14 +465,14 @@ static auto PerformAggregateAccess(EvalContext& eval_context, SemIR::Inst inst)
aggregate_id)) {
auto elements = eval_context.inst_blocks().Get(aggregate->elements_id);
auto index = static_cast<size_t>(access_inst.index.index);
CARBON_CHECK(index < elements.size()) << "Access out of bounds.";
CARBON_CHECK(index < elements.size(), "Access out of bounds.");
// `Phase` is not used here. If this element is a template constant, then
// so is the result of indexing, even if the aggregate also contains a
// symbolic context.
return eval_context.GetConstantValue(elements[index]);
} else {
CARBON_CHECK(phase != Phase::Template)
<< "Failed to evaluate template constant " << inst;
CARBON_CHECK(phase != Phase::Template,
"Failed to evaluate template constant {0}", inst);
}
}
return MakeNonConstantResult(phase);
@@ -490,8 +491,8 @@ static auto PerformAggregateIndex(EvalContext& eval_context, SemIR::Inst inst)
}
auto index = eval_context.insts().TryGetAs<SemIR::IntLiteral>(index_id);
if (!index) {
CARBON_CHECK(phase != Phase::Template)
<< "Template constant integer should be a literal";
CARBON_CHECK(phase != Phase::Template,
"Template constant integer should be a literal");
return MakeNonConstantResult(phase);
}
@@ -529,15 +530,15 @@ static auto PerformAggregateIndex(EvalContext& eval_context, SemIR::Inst inst)
auto aggregate =
eval_context.insts().TryGetAs<SemIR::AnyAggregateValue>(aggregate_id);
if (!aggregate) {
CARBON_CHECK(phase != Phase::Template)
<< "Unexpected representation for template constant aggregate";
CARBON_CHECK(phase != Phase::Template,
"Unexpected representation for template constant aggregate");
return MakeNonConstantResult(phase);
}
auto elements = eval_context.inst_blocks().Get(aggregate->elements_id);
// We checked this for the array case above.
CARBON_CHECK(index_val.ult(elements.size()))
<< "Index out of bounds in tuple indexing";
CARBON_CHECK(index_val.ult(elements.size()),
"Index out of bounds in tuple indexing");
return eval_context.GetConstantValue(elements[index_val.getZExtValue()]);
}
@@ -649,7 +650,7 @@ static auto PerformBuiltinUnaryIntOp(Context& context, SemIRLoc loc,
op_val.flipAllBits();
break;
default:
CARBON_FATAL() << "Unexpected builtin kind";
CARBON_FATAL("Unexpected builtin kind");
}
return MakeIntResult(context, op.type_id, std::move(op_val));
@@ -774,7 +775,7 @@ static auto PerformBuiltinBinaryIntOp(Context& context, SemIRLoc loc,
break;
default:
CARBON_FATAL() << "Unexpected operation kind.";
CARBON_FATAL("Unexpected operation kind.");
}
if (overflow) {
@@ -823,7 +824,7 @@ static auto PerformBuiltinIntComparison(Context& context,
result = is_signed ? lhs_val.sge(rhs_val) : lhs_val.sge(rhs_val);
break;
default:
CARBON_FATAL() << "Unexpected operation kind.";
CARBON_FATAL("Unexpected operation kind.");
}
return MakeBoolResult(context, bool_type_id, result);
@@ -842,7 +843,7 @@ static auto PerformBuiltinUnaryFloatOp(Context& context,
op_val.changeSign();
break;
default:
CARBON_FATAL() << "Unexpected builtin kind";
CARBON_FATAL("Unexpected builtin kind");
}
return MakeFloatResult(context, op.type_id, std::move(op_val));
@@ -875,7 +876,7 @@ static auto PerformBuiltinBinaryFloatOp(Context& context,
result_val = lhs_val / rhs_val;
break;
default:
CARBON_FATAL() << "Unexpected operation kind.";
CARBON_FATAL("Unexpected operation kind.");
}
return MakeFloatResult(context, lhs.type_id, std::move(result_val));
@@ -912,7 +913,7 @@ static auto PerformBuiltinFloatComparison(
result = lhs_val >= rhs_val;
break;
default:
CARBON_FATAL() << "Unexpected operation kind.";
CARBON_FATAL("Unexpected operation kind.");
}
return MakeBoolResult(context, bool_type_id, result);
@@ -926,7 +927,7 @@ static auto MakeConstantForBuiltinCall(Context& context, SemIRLoc loc,
Phase phase) -> SemIR::ConstantId {
switch (builtin_kind) {
case SemIR::BuiltinFunctionKind::None:
CARBON_FATAL() << "Not a builtin function.";
CARBON_FATAL("Not a builtin function.");
case SemIR::BuiltinFunctionKind::PrintInt: {
// Providing a constant result would allow eliding the function call.
@@ -1483,8 +1484,8 @@ auto TryEvalInstInContext(EvalContext& eval_context, SemIR::InstId inst_id,
break;
case SemIR::ImportRefUnloaded::Kind:
CARBON_FATAL()
<< "ImportRefUnloaded should be loaded before TryEvalInst: " << inst;
CARBON_FATAL("ImportRefUnloaded should be loaded before TryEvalInst: {0}",
inst);
}
return SemIR::ConstantId::NotConstant;
}