Author: rnk Date: Tue Nov 6 12:45:26 2018 New Revision: 346265 URL: http://llvm.org/viewvc/llvm-project?rev=346265&view=rev Log: [MS] Zero out ECX in __cpuid in intrin.h
Summary: Some CPUID leafs depend on the value of ECX as well as EAX, but we left it uninitialized. Originally reported as https://crbug.com/901547 Reviewers: craig.topper, hans Subscribers: cfe-commits Differential Revision: https://reviews.llvm.org/D54171 Added: cfe/trunk/test/CodeGen/ms-intrinsics-cpuid.c Modified: cfe/trunk/lib/Headers/intrin.h Modified: cfe/trunk/lib/Headers/intrin.h URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/lib/Headers/intrin.h?rev=346265&r1=346264&r2=346265&view=diff ============================================================================== --- cfe/trunk/lib/Headers/intrin.h (original) +++ cfe/trunk/lib/Headers/intrin.h Tue Nov 6 12:45:26 2018 @@ -535,7 +535,7 @@ __stosq(unsigned __int64 *__dst, unsigne static __inline__ void __DEFAULT_FN_ATTRS __cpuid(int __info[4], int __level) { __asm__ ("cpuid" : "=a"(__info[0]), "=b" (__info[1]), "=c"(__info[2]), "=d"(__info[3]) - : "a"(__level)); + : "a"(__level), "c"(0)); } static __inline__ void __DEFAULT_FN_ATTRS __cpuidex(int __info[4], int __level, int __ecx) { Added: cfe/trunk/test/CodeGen/ms-intrinsics-cpuid.c URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/test/CodeGen/ms-intrinsics-cpuid.c?rev=346265&view=auto ============================================================================== --- cfe/trunk/test/CodeGen/ms-intrinsics-cpuid.c (added) +++ cfe/trunk/test/CodeGen/ms-intrinsics-cpuid.c Tue Nov 6 12:45:26 2018 @@ -0,0 +1,18 @@ +// RUN: %clang_cc1 -ffreestanding -fms-extensions -fms-compatibility -fms-compatibility-version=17.00 \ +// RUN: -triple i686-windows-msvc -emit-llvm %s -o - | FileCheck %s +// RUN: %clang_cc1 -ffreestanding -fms-extensions -fms-compatibility -fms-compatibility-version=17.00 \ +// RUN: -triple x86_64-windows-msvc -emit-llvm %s -o - | FileCheck %s + +// intrin.h needs size_t, but -ffreestanding prevents us from getting it from +// stddef.h. Work around it with this typedef. +typedef __SIZE_TYPE__ size_t; + +#include <intrin.h> + +void test__cpuid(int *info, int level) { + __cpuid(info, level); +} +// CHECK-LABEL: define {{.*}} @test__cpuid(i32* %{{.*}}, i32 %{{.*}}) +// CHECK: call { i32, i32, i32, i32 } asm "cpuid", +// CHECK-SAME: "={ax},={bx},={cx},={dx},{ax},{cx},~{dirflag},~{fpsr},~{flags}" +// CHECK-SAME: (i32 %{{.*}}, i32 0) _______________________________________________ cfe-commits mailing list cfe-commits@lists.llvm.org http://lists.llvm.org/cgi-bin/mailman/listinfo/cfe-commits
