Author: Jeroen Dobbelaere Date: 2021-02-18T17:29:46+01:00 New Revision: 46757ccb49ab88da54ca8ddd43665d5255ee80f7
URL: https://github.com/llvm/llvm-project/commit/46757ccb49ab88da54ca8ddd43665d5255ee80f7 DIFF: https://github.com/llvm/llvm-project/commit/46757ccb49ab88da54ca8ddd43665d5255ee80f7.diff LOG: [clang] functions with the 'const' or 'pure' attribute must always return. As described in * https://gcc.gnu.org/onlinedocs/gcc/Common-Function-Attributes.html#index-pure-function-attribute * https://gcc.gnu.org/onlinedocs/gcc/Common-Function-Attributes.html#index-const-function-attribute An `__attribute__((pure))` function must always return, as well as an `__attribute__((const))` function. Reviewed By: jdoerfert Differential Revision: https://reviews.llvm.org/D96960 Added: Modified: clang/lib/CodeGen/CGCall.cpp clang/test/CodeGen/complex-builtins.c clang/test/CodeGen/complex-libcalls.c clang/test/CodeGen/function-attributes.c clang/test/CodeGenCXX/2009-05-04-PureConstNounwind.cpp clang/test/Sema/libbuiltins-ctype-powerpc64.c clang/test/Sema/libbuiltins-ctype-x86_64.c Removed: ################################################################################ diff --git a/clang/lib/CodeGen/CGCall.cpp b/clang/lib/CodeGen/CGCall.cpp index 405b4d2e1980..992e87319943 100644 --- a/clang/lib/CodeGen/CGCall.cpp +++ b/clang/lib/CodeGen/CGCall.cpp @@ -1994,9 +1994,14 @@ void CodeGenModule::ConstructAttributeList( if (TargetDecl->hasAttr<ConstAttr>()) { FuncAttrs.addAttribute(llvm::Attribute::ReadNone); FuncAttrs.addAttribute(llvm::Attribute::NoUnwind); + // gcc specifies that 'const' functions have greater restrictions than + // 'pure' functions, so they also cannot have infinite loops. + FuncAttrs.addAttribute(llvm::Attribute::WillReturn); } else if (TargetDecl->hasAttr<PureAttr>()) { FuncAttrs.addAttribute(llvm::Attribute::ReadOnly); FuncAttrs.addAttribute(llvm::Attribute::NoUnwind); + // gcc specifies that 'pure' functions cannot have infinite loops. + FuncAttrs.addAttribute(llvm::Attribute::WillReturn); } else if (TargetDecl->hasAttr<NoAliasAttr>()) { FuncAttrs.addAttribute(llvm::Attribute::ArgMemOnly); FuncAttrs.addAttribute(llvm::Attribute::NoUnwind); diff --git a/clang/test/CodeGen/complex-builtins.c b/clang/test/CodeGen/complex-builtins.c index 96c0e7117016..6fea8a9f028c 100644 --- a/clang/test/CodeGen/complex-builtins.c +++ b/clang/test/CodeGen/complex-builtins.c @@ -133,7 +133,7 @@ void foo(float f) { // NO__ERRNO: declare { x86_fp80, x86_fp80 } @cprojl({ x86_fp80, x86_fp80 }* byval({ x86_fp80, x86_fp80 }) align 16) [[NOT_READNONE]] // HAS_ERRNO: declare { double, double } @cproj(double, double) [[READNONE:#[0-9]+]] // HAS_ERRNO: declare <2 x float> @cprojf(<2 x float>) [[READNONE]] -// HAS_ERRNO: declare { x86_fp80, x86_fp80 } @cprojl({ x86_fp80, x86_fp80 }* byval({ x86_fp80, x86_fp80 }) align 16) [[NOT_READNONE]] +// HAS_ERRNO: declare { x86_fp80, x86_fp80 } @cprojl({ x86_fp80, x86_fp80 }* byval({ x86_fp80, x86_fp80 }) align 16) [[WILLRETURN_NOT_READNONE:#[0-9]+]] __builtin_cpow(f,f); __builtin_cpowf(f,f); __builtin_cpowl(f,f); @@ -202,3 +202,4 @@ void foo(float f) { // HAS_ERRNO: attributes [[NOT_READNONE]] = { nounwind {{.*}} } // HAS_ERRNO: attributes [[READNONE]] = { {{.*}}readnone{{.*}} } +// HAS_ERRNO: attributes [[WILLRETURN_NOT_READNONE]] = { nounwind willreturn {{.*}} } diff --git a/clang/test/CodeGen/complex-libcalls.c b/clang/test/CodeGen/complex-libcalls.c index 9bd419a83821..44d6849c0a71 100644 --- a/clang/test/CodeGen/complex-libcalls.c +++ b/clang/test/CodeGen/complex-libcalls.c @@ -133,7 +133,7 @@ void foo(float f) { // NO__ERRNO: declare { x86_fp80, x86_fp80 } @cprojl({ x86_fp80, x86_fp80 }* byval({ x86_fp80, x86_fp80 }) align 16) [[NOT_READNONE]] // HAS_ERRNO: declare { double, double } @cproj(double, double) [[READNONE:#[0-9]+]] // HAS_ERRNO: declare <2 x float> @cprojf(<2 x float>) [[READNONE]] -// HAS_ERRNO: declare { x86_fp80, x86_fp80 } @cprojl({ x86_fp80, x86_fp80 }* byval({ x86_fp80, x86_fp80 }) align 16) [[NOT_READNONE]] +// HAS_ERRNO: declare { x86_fp80, x86_fp80 } @cprojl({ x86_fp80, x86_fp80 }* byval({ x86_fp80, x86_fp80 }) align 16) [[WILLRETURN_NOT_READNONE:#[0-9]+]] cpow(f,f); cpowf(f,f); cpowl(f,f); @@ -202,3 +202,4 @@ void foo(float f) { // HAS_ERRNO: attributes [[NOT_READNONE]] = { nounwind {{.*}} } // HAS_ERRNO: attributes [[READNONE]] = { {{.*}}readnone{{.*}} } +// HAS_ERRNO: attributes [[WILLRETURN_NOT_READNONE]] = { nounwind willreturn {{.*}} } diff --git a/clang/test/CodeGen/function-attributes.c b/clang/test/CodeGen/function-attributes.c index ffb86a6cd272..f14f24801006 100644 --- a/clang/test/CodeGen/function-attributes.c +++ b/clang/test/CodeGen/function-attributes.c @@ -115,5 +115,5 @@ void f20(void) { // CHECK: attributes [[SR]] = { nounwind optsize{{.*}} "stackrealign"{{.*}} } // CHECK: attributes [[RT]] = { nounwind optsize returns_twice{{.*}} } // CHECK: attributes [[NR]] = { noreturn optsize } -// CHECK: attributes [[NUW_RN]] = { nounwind optsize readnone } +// CHECK: attributes [[NUW_RN]] = { nounwind optsize readnone willreturn } // CHECK: attributes [[RT_CALL]] = { optsize returns_twice } diff --git a/clang/test/CodeGenCXX/2009-05-04-PureConstNounwind.cpp b/clang/test/CodeGenCXX/2009-05-04-PureConstNounwind.cpp index 25400a552e5d..e1d539608fcc 100644 --- a/clang/test/CodeGenCXX/2009-05-04-PureConstNounwind.cpp +++ b/clang/test/CodeGenCXX/2009-05-04-PureConstNounwind.cpp @@ -15,8 +15,8 @@ int f(void) { // CHECK: declare i32 @_Z1tv() [[TF2:#[0-9]+]] // CHECK: attributes [[TF]] = { {{.*}} } -// CHECK: attributes [[NUW_RN]] = { nounwind readnone{{.*}} } -// CHECK: attributes [[NUW_RO]] = { nounwind readonly{{.*}} } +// CHECK: attributes [[NUW_RN]] = { nounwind readnone willreturn{{.*}} } +// CHECK: attributes [[NUW_RO]] = { nounwind readonly willreturn{{.*}} } // CHECK: attributes [[TF2]] = { {{.*}} } -// CHECK: attributes [[NUW_RN_CALL]] = { nounwind readnone } -// CHECK: attributes [[NUW_RO_CALL]] = { nounwind readonly } +// CHECK: attributes [[NUW_RN_CALL]] = { nounwind readnone willreturn } +// CHECK: attributes [[NUW_RO_CALL]] = { nounwind readonly willreturn } diff --git a/clang/test/Sema/libbuiltins-ctype-powerpc64.c b/clang/test/Sema/libbuiltins-ctype-powerpc64.c index bfd79acb0ab0..ba0efb205944 100644 --- a/clang/test/Sema/libbuiltins-ctype-powerpc64.c +++ b/clang/test/Sema/libbuiltins-ctype-powerpc64.c @@ -62,4 +62,4 @@ void test(int x) { // CHECK: declare signext i32 @toupper(i32 signext) [[NUW_RO:#[0-9]+]] // CHECK: attributes [[NUW_RO]] = { nounwind readonly{{.*}} } -// CHECK: attributes [[NUW_RO_CALL]] = { nounwind readonly } +// CHECK: attributes [[NUW_RO_CALL]] = { nounwind readonly willreturn } diff --git a/clang/test/Sema/libbuiltins-ctype-x86_64.c b/clang/test/Sema/libbuiltins-ctype-x86_64.c index 4934e6f16752..b8a2c7e81584 100644 --- a/clang/test/Sema/libbuiltins-ctype-x86_64.c +++ b/clang/test/Sema/libbuiltins-ctype-x86_64.c @@ -62,4 +62,4 @@ void test(int x) { // CHECK: declare i32 @toupper(i32) [[NUW_RO:#[0-9]+]] // CHECK: attributes [[NUW_RO]] = { nounwind readonly{{.*}} } -// CHECK: attributes [[NUW_RO_CALL]] = { nounwind readonly } +// CHECK: attributes [[NUW_RO_CALL]] = { nounwind readonly willreturn } _______________________________________________ cfe-commits mailing list cfe-commits@lists.llvm.org https://lists.llvm.org/cgi-bin/mailman/listinfo/cfe-commits
