llvmbot wrote:
<!--LLVM PR SUMMARY COMMENT--> @llvm/pr-subscribers-clang-codegen Author: Zahira Ammarguellat (zahiraam) <details> <summary>Changes</summary> In https://github.com/llvm/llvm-project/pull/100302, `int` TBAA information was added to math function calls to indicate the type of non-argument memory a function might modify. The purpose of this change was to avoid that some math functions (math functions modify errno) be a barrier to various code motion. Complex functions have pointer arguments. The `int` TBAA attached to the function is interpreted as describing those arguments instead of the type that arguments are pointing to. This small example: ``` double b; void a() { __builtin_cargl(b); } ``` compiled with `-fmath-errno -O3` will generate this call: `%call = tail call x86_fp80 @<!-- -->cargl(ptr noundef nonnull byval({ x86_fp80, x86_fp80 }) align 16 %byval-temp) #<!-- -->3, !tbaa !9 ` ``` 9 = !{!10, !10, i64 0} !10 = !{!"int", !7, i64 0} ``` The TBBA attached to the argument of `__builtin_cargl` is `int`, but that’s not correct. This patch fixes this issue: calls of functions that have pointer arguments or calls functions that return a pointer are restricted from the TBBA information. --- Full diff: https://github.com/llvm/llvm-project/pull/107598.diff 2 Files Affected: - (modified) clang/lib/CodeGen/CGBuiltin.cpp (+13-2) - (added) clang/test/CodeGen/complex-math-libcalls-tbaa.c (+31) ``````````diff diff --git a/clang/lib/CodeGen/CGBuiltin.cpp b/clang/lib/CodeGen/CGBuiltin.cpp index e4d169d2ad6030..ed8a977c8088ab 100644 --- a/clang/lib/CodeGen/CGBuiltin.cpp +++ b/clang/lib/CodeGen/CGBuiltin.cpp @@ -699,9 +699,20 @@ static RValue emitLibraryCall(CodeGenFunction &CGF, const FunctionDecl *FD, bool ConstWithoutErrnoAndExceptions = Context.BuiltinInfo.isConstWithoutErrnoAndExceptions(BuiltinID); // Restrict to target with errno, for example, MacOS doesn't set errno. - // TODO: Support builtin function with complex type returned, eg: cacosh + bool CallWithPointerArgsOrPointerReturnType = false; + if (Call.isScalar() && Call.getScalarVal()) { + if (CallBase *CB = dyn_cast<CallBase>(Call.getScalarVal())) { + for (Value *A : CB->args()) + if (A->getType()->isPointerTy()) + CallWithPointerArgsOrPointerReturnType = true; + CallWithPointerArgsOrPointerReturnType = + CallWithPointerArgsOrPointerReturnType || + CB->getFunctionType()->getReturnType()->isPointerTy(); + } + } if (ConstWithoutErrnoAndExceptions && CGF.CGM.getLangOpts().MathErrno && - !CGF.Builder.getIsFPConstrained() && Call.isScalar()) { + !CGF.Builder.getIsFPConstrained() && Call.isScalar() && + !CallWithPointerArgsOrPointerReturnType) { // Emit "int" TBAA metadata on FP math libcalls. clang::QualType IntTy = Context.IntTy; TBAAAccessInfo TBAAInfo = CGF.CGM.getTBAAAccessInfo(IntTy); diff --git a/clang/test/CodeGen/complex-math-libcalls-tbaa.c b/clang/test/CodeGen/complex-math-libcalls-tbaa.c new file mode 100644 index 00000000000000..957dae6361b6f6 --- /dev/null +++ b/clang/test/CodeGen/complex-math-libcalls-tbaa.c @@ -0,0 +1,31 @@ +// RUN: %clang_cc1 %s -O3 -fmath-errno -emit-llvm -triple x86_64-unknown-unknown -o - %s | FileCheck %s -check-prefixes=CHECK +// RUN: %clang_cc1 %s -O3 -fmath-errno -emit-llvm -triple x86_64-pc-win64 -o - %s | FileCheck %s -check-prefixes=CHECK +// RUN: %clang_cc1 %s -O3 -fmath-errno -emit-llvm -triple i686-unknown-unknown -o - %s | FileCheck %s -check-prefixes=CHECK +// RUN: %clang_cc1 %s -O3 -fmath-errno -emit-llvm -triple powerpc-unknown-unknown -o - %s | FileCheck %s -check-prefixes=CHECK-PPC +// RUN: %clang_cc1 %s -O3 -fmath-errno -emit-llvm -triple armv7-none-linux-gnueabi -o - %s | FileCheck %s -check-prefixes=CHECK-TBAA,TBAA +// RUN: %clang_cc1 %s -O3 -fmath-errno -emit-llvm -triple armv7-none-linux-gnueabihf -o - %s | FileCheck %s -check-prefixes=CHECK-ARM,TBAA +// RUN: %clang_cc1 %s -O3 -fmath-errno -emit-llvm -triple thumbv7k-apple-watchos2.0 -o - -target-abi aapcs16 %s | FileCheck %s -check-prefixes=CHECK-THUMB,TBAA +// RUN: %clang_cc1 %s -O3 -fmath-errno -emit-llvm -triple aarch64-unknown-unknown -o - %s | FileCheck %s -check-prefixes=CHECK-AARCH,TBAA +// RUN: %clang_cc1 %s -O3 -fmath-errno -emit-llvm -triple spir -o - %s | FileCheck %s -check-prefixes=CHECK-SPIR + +_Complex long double foo() { + _Complex long double cld; + long double v2 = __builtin_cargl(cld); + _Complex long double tmp = v2 * cld; + return tmp; +} +// CHECK: tail call x86_fp80 @cargl(ptr noundef nonnull byval({ {{.*}}, {{.*}} }) +// CHECK-PPC: tail call ppc_fp128 @cargl(ptr noundef nonnull byval({ ppc_fp128, ppc_fp128 }) +// CHECK-TBAA: tail call double @cargl([2 x i64] noundef undef) #[[ATTR1:[0-9]+]], !tbaa [[TBAA3:![0-9]+]] + +// CHECK-ARM: tail call double @cargl({ double, double } noundef undef) #[[ATTR1:[0-9]+]], !tbaa [[TBAA3:![0-9]+]] + +// CHECK-THUMB: tail call double @cargl([2 x double] noundef undef) #[[ATTR1:[0-9]+]], !tbaa [[TBAA3:![0-9]+]] + +// CHECK-AARCH: tail call fp128 @cargl([2 x fp128] noundef alignstack(16) undef) #[[ATTR1:[0-9]+]], !tbaa [[TBAA3:![0-9]+]] + +// CHECK-SPIR: tail call spir_func double @cargl(ptr noundef nonnull byval({ {{.*}}, {{.*}} }) + +// TBAA: [[TBAA3]] = !{[[META4:![0-9]+]], [[META4]], i64 0} +// TBAA: [[META4]] = !{!"int", [[META5:![0-9]+]], i64 0} +// TBAA: [[META5]] = !{!"omnipotent char", [[META6:![0-9]+]], i64 0} `````````` </details> https://github.com/llvm/llvm-project/pull/107598 _______________________________________________ cfe-commits mailing list cfe-commits@lists.llvm.org https://lists.llvm.org/cgi-bin/mailman/listinfo/cfe-commits
