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Always honor fp-contract pragmas on PlayStation #162549

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6 changes: 5 additions & 1 deletion clang/lib/CodeGen/BackendUtil.cpp
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Original file line number Diff line number Diff line change
Expand Up @@ -406,7 +406,11 @@ static bool initTargetOptions(const CompilerInstance &CI,
Options.AllowFPOpFusion = llvm::FPOpFusion::Standard;
break;
case LangOptions::FPM_Fast:
Options.AllowFPOpFusion = llvm::FPOpFusion::Fast;
// We always honor fp-contract pragmas for PlayStation.
if (CI.getASTContext().getTargetInfo().getTriple().isPS())
Options.AllowFPOpFusion = llvm::FPOpFusion::Standard;
else
Options.AllowFPOpFusion = llvm::FPOpFusion::Fast;
break;
}

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53 changes: 53 additions & 0 deletions clang/test/CodeGen/X86/fma-fast-pragma.cpp
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@@ -0,0 +1,53 @@
// REQUIRES: x86-registered-target

// With the pragma in place, generic targets leave FMA enabled unless the
// switch '-ffp-contract=fast-honor-pragmas' is used to disable it; whereas
// for PlayStation, the pragma is always honored, so FMA is disabled even in
// plain 'fast' mode:
// RUN: %clang_cc1 -S -triple x86_64-unknown-unknown -target-feature +fma \
// RUN: -O2 -ffp-contract=fast -o - %s | \
// RUN: FileCheck --check-prefix=CHECK-YES-FMA %s
// RUN: %clang_cc1 -S -triple x86_64-unknown-unknown -target-feature +fma \
// RUN: -O2 -ffp-contract=fast-honor-pragmas -o - %s | \
// RUN: FileCheck --check-prefix=CHECK-NO-FMA %s
// RUN: %clang_cc1 -S -triple x86_64-unknown-unknown -target-feature +fma \
// RUN: -O2 -ffp-contract=fast -ffp-contract=fast-honor-pragmas -o - %s | \
// RUN: FileCheck --check-prefix=CHECK-NO-FMA %s
// RUN: %clang_cc1 -S -triple x86_64-sie-ps5 -target-feature +fma \
// RUN: -O2 -ffp-contract=fast -o - %s | \
// RUN: FileCheck --check-prefix=CHECK-NO-FMA %s
// RUN: %clang_cc1 -S -triple x86_64-sie-ps5 -target-feature +fma \
// RUN: -O2 -ffp-contract=fast-honor-pragmas -o - %s | \
// RUN: FileCheck --check-prefix=CHECK-NO-FMA %s
//
// With the pragma suppressed, FMA happens in 'fast' or 'fast-honor-pragmas'
// modes (for generic targets and for PlayStation):
// RUN: %clang_cc1 -S -DSUPPRESS_PRAGMA \
// RUN: -triple x86_64-unknown-unknown -target-feature +fma \
// RUN: -O2 -ffp-contract=fast -o - %s | \
// RUN: FileCheck --check-prefix=CHECK-YES-FMA %s
// RUN: %clang_cc1 -S -DSUPPRESS_PRAGMA \
// RUN: -triple x86_64-unknown-unknown -target-feature +fma \
// RUN: -O2 -ffp-contract=fast-honor-pragmas -o - %s | \
// RUN: FileCheck --check-prefix=CHECK-YES-FMA %s
// RUN: %clang_cc1 -S -DSUPPRESS_PRAGMA \
// RUN: -triple x86_64-sie-ps5 -target-feature +fma \
// RUN: -O2 -ffp-contract=fast -o - %s | \
// RUN: FileCheck --check-prefix=CHECK-YES-FMA %s
// RUN: %clang_cc1 -S -DSUPPRESS_PRAGMA \
// RUN: -triple x86_64-sie-ps5 -target-feature +fma \
// RUN: -O2 -ffp-contract=fast-honor-pragmas -o - %s | \
// RUN: FileCheck --check-prefix=CHECK-YES-FMA %s
//
float compute(float a, float b, float c) {
#if !defined(SUPPRESS_PRAGMA)
#pragma clang fp contract (off)
#endif
float product = a * b;
return product + c;
}

// CHECK-NO-FMA: vmulss
// CHECK-NO-FMA-NEXT: vaddss

// CHECK-YES-FMA: vfmadd213ss