[clang] d9717d8 - [X86] Add a memory clobber to the bittest intrinsic inline asm. Get default clobbers from the target

[Craig Topper via cfe-commits]

Author: Craig Topper
Date: 2020-09-23T14:54:39-07:00
New Revision: d9717d8ee7143f4f5b768dfb5e8629ecfa067e39

URL: https://github.com/llvm/llvm-project/commit/d9717d8ee7143f4f5b768dfb5e8629ecfa067e39
DIFF: https://github.com/llvm/llvm-project/commit/d9717d8ee7143f4f5b768dfb5e8629ecfa067e39.diff

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

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

Differential Revision: https://reviews.llvm.org/D88121

Added: 
    

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

Removed: 
    


################################################################################
diff  --git a/clang/lib/CodeGen/CGBuiltin.cpp b/clang/lib/CodeGen/CGBuiltin.cpp
index 92c537f32b59..9bdb21e0c05b 100644
--- a/clang/lib/CodeGen/CGBuiltin.cpp
+++ b/clang/lib/CodeGen/CGBuiltin.cpp
@@ -808,7 +808,12 @@ static llvm::Value *EmitX86BitTestIntrinsic(CodeGenFunction &CGF,
   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},~{flags},~{fpsr}";
+  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()));

diff  --git a/clang/test/CodeGen/bittest-intrin.c b/clang/test/CodeGen/bittest-intrin.c
index edbae4ab9172..ddc2af5454d7 100644
--- a/clang/test/CodeGen/bittest-intrin.c
+++ b/clang/test/CodeGen/bittest-intrin.c
@@ -34,20 +34,20 @@ void test_arm(long *base, long idx) {
 #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 {{.*}})
-// X64: call i8 asm sideeffect "btcq $2, ($1)\0A\09setc ${0:b}", "=r,r,r,~{{.*}}"(i64* %{{.*}}, i64 {{.*}})
-// X64: call i8 asm sideeffect "btrq $2, ($1)\0A\09setc ${0:b}", "=r,r,r,~{{.*}}"(i64* %{{.*}}, i64 {{.*}})
-// X64: call i8 asm sideeffect "btsq $2, ($1)\0A\09setc ${0:b}", "=r,r,r,~{{.*}}"(i64* %{{.*}}, i64 {{.*}})
-// X64: call i8 asm sideeffect "lock btrq $2, ($1)\0A\09setc ${0:b}", "=r,r,r,~{{.*}}"(i64* %{{.*}}, i64 {{.*}})
-// X64: call i8 asm sideeffect "lock btsq $2, ($1)\0A\09setc ${0:b}", "=r,r,r,~{{.*}}"(i64* %{{.*}}, i64 {{.*}})
+// X64: call i8 asm sideeffect "btq $2, ($1)\0A\09setc ${0:b}", "=r,r,r,~{cc},~{memory},~{dirflag},~{fpsr},~{flags}"(i64* %{{.*}}, i64 {{.*}})
+// X64: call i8 asm sideeffect "btcq $2, ($1)\0A\09setc ${0:b}", "=r,r,r,~{cc},~{memory},~{dirflag},~{fpsr},~{flags}"(i64* %{{.*}}, i64 {{.*}})
+// X64: call i8 asm sideeffect "btrq $2, ($1)\0A\09setc ${0:b}", "=r,r,r,~{cc},~{memory},~{dirflag},~{fpsr},~{flags}"(i64* %{{.*}}, i64 {{.*}})
+// X64: call i8 asm sideeffect "btsq $2, ($1)\0A\09setc ${0:b}", "=r,r,r,~{cc},~{memory},~{dirflag},~{fpsr},~{flags}"(i64* %{{.*}}, i64 {{.*}})
+// X64: call i8 asm sideeffect "lock btrq $2, ($1)\0A\09setc ${0:b}", "=r,r,r,~{cc},~{memory},~{dirflag},~{fpsr},~{flags}"(i64* %{{.*}}, i64 {{.*}})
+// X64: call i8 asm sideeffect "lock btsq $2, ($1)\0A\09setc ${0:b}", "=r,r,r,~{cc},~{memory},~{dirflag},~{fpsr},~{flags}"(i64* %{{.*}}, i64 {{.*}})
 
 // ARM-LABEL: define dso_local {{.*}}void @test32(i32* %base, i32 %idx)
 // ARM: %[[IDXHI:[^ ]*]] = ashr i32 %{{.*}}, 3