commit 42c15c7edf174fc7a45131a1b89ee816fada7633
author Phoebe Wang <pengfei.wang@intel.com> Tue Nov 30 13:19:20 2021 +0800
committer Phoebe Wang <pengfei.wang@intel.com> Tue Nov 30 14:08:10 2021 +0800
tree 109e69d0f85e79e82cec6d42c5032ed31d45ed83
parent a88bb5b9fee5aee8c25cabad44a257175e384f52

[X86][clang] Enable floating-point type for -mno-x87 option on 32-bits

We should match GCC's behavior which allows floating-point type for -mno-x87 option on 32-bits. https://godbolt.org/z/KrbhfWc9o

The previous block issues have partially been fixed by D112143.

Reviewed By: asavonic, nickdesaulniers

Differential Revision: https://reviews.llvm.org/D114162

clang/lib/Basic/Targets/X86.cpp

diff --git a/clang/lib/Basic/Targets/X86.cpp b/clang/lib/Basic/Targets/X86.cpp
index 454a774..5c4bd36 100644
--- a/clang/lib/Basic/Targets/X86.cpp
+++ b/clang/lib/Basic/Targets/X86.cpp
@@ -382,12 +382,10 @@
   SimdDefaultAlign =
       hasFeature("avx512f") ? 512 : hasFeature("avx") ? 256 : 128;
 
-  if (!HasX87) {
-    if (LongDoubleFormat == &llvm::APFloat::x87DoubleExtended())
-      HasLongDouble = false;
-    if (getTriple().getArch() == llvm::Triple::x86)
-      HasFPReturn = false;
-  }
+  // FIXME: We should allow long double type on 32-bits to match with GCC.
+  // This requires backend to be able to lower f80 without x87 first.
+  if (!HasX87 && LongDoubleFormat == &llvm::APFloat::x87DoubleExtended())
+    HasLongDouble = false;
 
   return true;
 }

clang/test/Sema/x86-no-x87.cpp

diff --git a/clang/test/Sema/x86-no-x87.cpp b/clang/test/Sema/x86-no-x87.cpp
index 112f6bf..2421ea1 100644
--- a/clang/test/Sema/x86-no-x87.cpp
+++ b/clang/test/Sema/x86-no-x87.cpp
@@ -1,4 +1,4 @@
-// RUN: %clang_cc1 -fsyntax-only -verify %s -triple i686-linux-gnu -target-feature -x87 -DRET_ERROR
+// RUN: %clang_cc1 -fsyntax-only -verify %s -triple i686-linux-gnu -target-feature -x87
 // RUN: %clang_cc1 -fsyntax-only -verify %s -triple i686-linux-gnu -DNOERROR
 
 #ifdef NOERROR
@@ -123,42 +123,22 @@
   long_double ld = 0.42;
 }
 
-#ifndef NOERROR
-// expected-note@+3{{'d_ret1' defined here}}
-// expected-error@+2{{'d_ret1' requires  'double' return type support, but target 'i686-unknown-linux-gnu' does not support it}}
-#endif
 double d_ret1(float x) {
   return 0.0;
 }
 
-#ifndef NOERROR
-// expected-note@+2{{'d_ret2' defined here}}
-#endif
 double d_ret2(float x);
 
 int d_ret3(float x) {
-#ifndef NOERROR
-  // expected-error@+2{{'d_ret2' requires  'double' return type support, but target 'i686-unknown-linux-gnu' does not support it}}
-#endif
   return (int)d_ret2(x);
 }
 
-#ifndef NOERROR
-// expected-note@+3{{'f_ret1' defined here}}
-// expected-error@+2{{'f_ret1' requires  'float' return type support, but target 'i686-unknown-linux-gnu' does not support it}}
-#endif
 float f_ret1(float x) {
   return 0.0f;
 }
 
-#ifndef NOERROR
-// expected-note@+2{{'f_ret2' defined here}}
-#endif
 float f_ret2(float x);
 
 int f_ret3(float x) {
-#ifndef NOERROR
-  // expected-error@+2{{'f_ret2' requires  'float' return type support, but target 'i686-unknown-linux-gnu' does not support it}}
-#endif
   return (int)f_ret2(x);
 }