Author: Zahira Ammarguellat Date: 2023-09-19T09:13:02-04:00 New Revision: a292e7edf8b2fc51d3e86a96ff5dff45d16bd264
URL: https://github.com/llvm/llvm-project/commit/a292e7edf8b2fc51d3e86a96ff5dff45d16bd264 DIFF: https://github.com/llvm/llvm-project/commit/a292e7edf8b2fc51d3e86a96ff5dff45d16bd264.diff LOG: Fix math-errno issue (#66381) Update handling of math errno. This change updates the logic for generation of math intrinics in place of math library function calls. The previous logic https://reviews.llvm.org/D151834 was incorrectly using intrinsics when math errno handling was needed at optimization levels above -O0. This also fixes issue mentioned in https://reviews.llvm.org/D151834 by @uabelho This is joint work with @andykaylor Andy. Added: Modified: clang/lib/CodeGen/CGBuiltin.cpp clang/test/CodeGen/math-builtins.c clang/test/CodeGen/math-libcalls.c Removed: ################################################################################ diff --git a/clang/lib/CodeGen/CGBuiltin.cpp b/clang/lib/CodeGen/CGBuiltin.cpp index 52868ca260290b7..f727a0d5592effd 100644 --- a/clang/lib/CodeGen/CGBuiltin.cpp +++ b/clang/lib/CodeGen/CGBuiltin.cpp @@ -2312,8 +2312,8 @@ RValue CodeGenFunction::EmitBuiltinExpr(const GlobalDecl GD, unsigned BuiltinID, const unsigned BuiltinIDIfNoAsmLabel = FD->hasAttr<AsmLabelAttr>() ? 0 : BuiltinID; - bool ErrnoOverriden = false; - // True if math-errno is overriden via the + std::optional<bool> ErrnoOverriden; + // ErrnoOverriden is true if math-errno is overriden via the // '#pragma float_control(precise, on)'. This pragma disables fast-math, // which implies math-errno. if (E->hasStoredFPFeatures()) { @@ -2329,8 +2329,8 @@ RValue CodeGenFunction::EmitBuiltinExpr(const GlobalDecl GD, unsigned BuiltinID, // using the '#pragma float_control(precise, off)', and // attribute opt-none hasn't been seen. bool ErrnoOverridenToFalseWithOpt = - !ErrnoOverriden && !OptNone && - CGM.getCodeGenOpts().OptimizationLevel != 0; + ErrnoOverriden.has_value() && !ErrnoOverriden.value() && !OptNone && + CGM.getCodeGenOpts().OptimizationLevel != 0; // There are LLVM math intrinsics/instructions corresponding to math library // functions except the LLVM op will never set errno while the math library @@ -2339,6 +2339,30 @@ RValue CodeGenFunction::EmitBuiltinExpr(const GlobalDecl GD, unsigned BuiltinID, // LLVM counterparts if the call is marked 'const' (known to never set errno). // In case FP exceptions are enabled, the experimental versions of the // intrinsics model those. + bool ConstAlways = + getContext().BuiltinInfo.isConst(BuiltinID); + + // There's a special case with the fma builtins where they are always const + // if the target environment is GNU or the target is OS is Windows and we're + // targeting the MSVCRT.dll environment. + // FIXME: This list can be become outdated. Need to find a way to get it some + // other way. + switch (BuiltinID) { + case Builtin::BI__builtin_fma: + case Builtin::BI__builtin_fmaf: + case Builtin::BI__builtin_fmal: + case Builtin::BIfma: + case Builtin::BIfmaf: + case Builtin::BIfmal: { + auto &Trip = CGM.getTriple(); + if (Trip.isGNUEnvironment() || Trip.isOSMSVCRT()) + ConstAlways = true; + break; + } + default: + break; + } + bool ConstWithoutErrnoAndExceptions = getContext().BuiltinInfo.isConstWithoutErrnoAndExceptions(BuiltinID); bool ConstWithoutExceptions = @@ -2362,14 +2386,17 @@ RValue CodeGenFunction::EmitBuiltinExpr(const GlobalDecl GD, unsigned BuiltinID, bool ConstWithoutErrnoOrExceptions = ConstWithoutErrnoAndExceptions || ConstWithoutExceptions; bool GenerateIntrinsics = - FD->hasAttr<ConstAttr>() && !ErrnoOverriden && !OptNone; + (ConstAlways && !OptNone) || + (!getLangOpts().MathErrno && + !(ErrnoOverriden.has_value() && ErrnoOverriden.value()) && !OptNone); if (!GenerateIntrinsics) { GenerateIntrinsics = ConstWithoutErrnoOrExceptions && !ConstWithoutErrnoAndExceptions; if (!GenerateIntrinsics) GenerateIntrinsics = ConstWithoutErrnoOrExceptions && - (!getLangOpts().MathErrno && !ErrnoOverriden && !OptNone); + (!getLangOpts().MathErrno && + !(ErrnoOverriden.has_value() && ErrnoOverriden.value()) && !OptNone); if (!GenerateIntrinsics) GenerateIntrinsics = ConstWithoutErrnoOrExceptions && ErrnoOverridenToFalseWithOpt; diff --git a/clang/test/CodeGen/math-builtins.c b/clang/test/CodeGen/math-builtins.c index 962e311698f5755..554c604219957ca 100644 --- a/clang/test/CodeGen/math-builtins.c +++ b/clang/test/CodeGen/math-builtins.c @@ -1,5 +1,7 @@ // RUN: %clang_cc1 -triple x86_64-unknown-unknown -w -S -o - -emit-llvm %s | FileCheck %s -check-prefix=NO__ERRNO // RUN: %clang_cc1 -triple x86_64-unknown-unknown -w -S -o - -emit-llvm -fmath-errno %s | FileCheck %s -check-prefix=HAS_ERRNO +// RUN: %clang_cc1 -triple x86_64-unknown-unknown -w -S -o - -emit-llvm -disable-llvm-passes -O2 %s | FileCheck %s -check-prefix=NO__ERRNO +// RUN: %clang_cc1 -triple x86_64-unknown-unknown -w -S -o - -emit-llvm -disable-llvm-passes -O2 -fmath-errno %s | FileCheck %s -check-prefix=HAS_ERRNO // RUN: %clang_cc1 -triple x86_64-unknown-unknown-gnu -w -S -o - -emit-llvm -fmath-errno %s | FileCheck %s --check-prefix=HAS_ERRNO_GNU // RUN: %clang_cc1 -triple x86_64-unknown-windows-msvc -w -S -o - -emit-llvm -fmath-errno %s | FileCheck %s --check-prefix=HAS_ERRNO_WIN diff --git a/clang/test/CodeGen/math-libcalls.c b/clang/test/CodeGen/math-libcalls.c index fa8f49d8a2c9ff4..02df4fe5fea6018 100644 --- a/clang/test/CodeGen/math-libcalls.c +++ b/clang/test/CodeGen/math-libcalls.c @@ -1,5 +1,7 @@ // RUN: %clang_cc1 -triple x86_64-unknown-unknown -Wno-implicit-function-declaration -w -S -o - -emit-llvm %s | FileCheck %s --check-prefix=NO__ERRNO // RUN: %clang_cc1 -triple x86_64-unknown-unknown -Wno-implicit-function-declaration -w -S -o - -emit-llvm -fmath-errno %s | FileCheck %s --check-prefix=HAS_ERRNO +// RUN: %clang_cc1 -triple x86_64-unknown-unknown -Wno-implicit-function-declaration -w -S -o - -emit-llvm -disable-llvm-passes -O2 %s | FileCheck %s --check-prefix=NO__ERRNO +// RUN: %clang_cc1 -triple x86_64-unknown-unknown -Wno-implicit-function-declaration -w -S -o - -emit-llvm -disable-llvm-passes -O2 -fmath-errno %s | FileCheck %s --check-prefix=HAS_ERRNO // RUN: %clang_cc1 -triple x86_64-unknown-unknown -Wno-implicit-function-declaration -w -S -o - -emit-llvm -ffp-exception-behavior=maytrap %s | FileCheck %s --check-prefix=HAS_MAYTRAP // RUN: %clang_cc1 -triple x86_64-unknown-unknown-gnu -Wno-implicit-function-declaration -w -S -o - -emit-llvm -fmath-errno %s | FileCheck %s --check-prefix=HAS_ERRNO_GNU // RUN: %clang_cc1 -triple x86_64-unknown-windows-msvc -Wno-implicit-function-declaration -w -S -o - -emit-llvm -fmath-errno %s | FileCheck %s --check-prefix=HAS_ERRNO_WIN _______________________________________________ cfe-commits mailing list cfe-commits@lists.llvm.org https://lists.llvm.org/cgi-bin/mailman/listinfo/cfe-commits
