[PATCH] D88121: [X86] Add a memory clobber to the bittest intrinsic inline asm. Get default clobbers from the target

[Craig Topper via Phabricator via cfe-commits]

craig.topper created this revision.
craig.topper added reviewers: RKSimon, spatel, rnk, echristo.
craig.topper requested review of this revision.

I believe the inline asm emitted here should have a memory clobber since it writes to memory.

It was also missing the dirflag clobber that we use by default along with flags and fpsr. To avoid missing defaults in the future, get the default list from the target


https://reviews.llvm.org/D88121

Files:
  clang/lib/CodeGen/CGBuiltin.cpp
  clang/test/CodeGen/bittest-intrin.c


Index: clang/test/CodeGen/bittest-intrin.c
===================================================================
--- clang/test/CodeGen/bittest-intrin.c
+++ clang/test/CodeGen/bittest-intrin.c
@@ -34,12 +34,12 @@
 #endif
 
 // X64-LABEL: define dso_local void @test32(i32* %base, i32 %idx)
-// X64: call i8 asm sideeffect "btl $2, ($1)\0A\09setc ${0:b}", "=r,r,r,~{{.*}}"(i32* %{{.*}}, i32 {{.*}})
-// X64: call i8 asm sideeffect "btcl $2, ($1)\0A\09setc ${0:b}", "=r,r,r,~{{.*}}"(i32* %{{.*}}, i32 {{.*}})
-// X64: call i8 asm sideeffect "btrl $2, ($1)\0A\09setc ${0:b}", "=r,r,r,~{{.*}}"(i32* %{{.*}}, i32 {{.*}})
-// X64: call i8 asm sideeffect "btsl $2, ($1)\0A\09setc ${0:b}", "=r,r,r,~{{.*}}"(i32* %{{.*}}, i32 {{.*}})
-// X64: call i8 asm sideeffect "lock btrl $2, ($1)\0A\09setc ${0:b}", "=r,r,r,~{{.*}}"(i32* %{{.*}}, i32 {{.*}})
-// X64: call i8 asm sideeffect "lock btsl $2, ($1)\0A\09setc ${0:b}", "=r,r,r,~{{.*}}"(i32* %{{.*}}, i32 {{.*}})
+// X64: call i8 asm sideeffect "btl $2, ($1)\0A\09setc ${0:b}", "=r,r,r,~{cc},~{memory},~{dirflag},~{fpsr},~{flags}"(i32* %{{.*}}, i32 {{.*}})
+// X64: call i8 asm sideeffect "btcl $2, ($1)\0A\09setc ${0:b}", "=r,r,r,~{cc},~{memory},~{dirflag},~{fpsr},~{flags}"(i32* %{{.*}}, i32 {{.*}})
+// X64: call i8 asm sideeffect "btrl $2, ($1)\0A\09setc ${0:b}", "=r,r,r,~{cc},~{memory},~{dirflag},~{fpsr},~{flags}"(i32* %{{.*}}, i32 {{.*}})
+// X64: call i8 asm sideeffect "btsl $2, ($1)\0A\09setc ${0:b}", "=r,r,r,~{cc},~{memory},~{dirflag},~{fpsr},~{flags}"(i32* %{{.*}}, i32 {{.*}})
+// X64: call i8 asm sideeffect "lock btrl $2, ($1)\0A\09setc ${0:b}", "=r,r,r,~{cc},~{memory},~{dirflag},~{fpsr},~{flags}"(i32* %{{.*}}, i32 {{.*}})
+// X64: call i8 asm sideeffect "lock btsl $2, ($1)\0A\09setc ${0:b}", "=r,r,r,~{cc},~{memory},~{dirflag},~{fpsr},~{flags}"(i32* %{{.*}}, i32 {{.*}})
 
 // X64-LABEL: define dso_local void @test64(i64* %base, i64 %idx)
 // X64: call i8 asm sideeffect "btq $2, ($1)\0A\09setc ${0:b}", "=r,r,r,~{{.*}}"(i64* %{{.*}}, i64 {{.*}})
Index: clang/lib/CodeGen/CGBuiltin.cpp
===================================================================
--- clang/lib/CodeGen/CGBuiltin.cpp
+++ clang/lib/CodeGen/CGBuiltin.cpp
@@ -808,8 +808,12 @@
   AsmOS << SizeSuffix << " $2, ($1)\n\tsetc ${0:b}";
 
   // Build the constraints. FIXME: We should support immediates when possible.
-  std::string Constraints =
-      "=r,r,r,~{cc},~{memory},~{fpsr},~{dirflag},~{flags}";
+  std::string Constraints = "=r,r,r,~{cc},~{memory}";
+  std::string MachineClobbers = CGF.getTarget().getClobbers();
+  if (!MachineClobbers.empty()) {
+    Constraints += ',';
+    Constraints += MachineClobbers;
+  }
   llvm::IntegerType *IntType = llvm::IntegerType::get(
       CGF.getLLVMContext(),
       CGF.getContext().getTypeSize(E->getArg(1)->getType()));


-------------- next part --------------
A non-text attachment was scrubbed...
Name: D88121.293586.patch
Type: text/x-patch
Size: 2802 bytes
Desc: not available
URL: <http://lists.llvm.org/pipermail/cfe-commits/attachments/20200922/1ea080ec/attachment.bin>