[ObjC] Use consistent comment style in inline asm

[olista01]

Summary

The comment markers accepted by the assembler vary between different targets, but '//' is always accepted, so we should use that for consistency.

[olista01]

Ping.

[SjoerdMeijer]

Looks reasonable to me.

lib/CodeGen/TargetInfo.cpp

unsigned Sig = (0xeb << 0) |  // jmp rel8
                    (0x06 << 8) |  //           .+0x08
                    ('F' << 16) |
                    ('T' << 24);
     return llvm::ConstantInt::get(CGM.Int32Ty, Sig);
   }
 
   StringRef getARCRetainAutoreleasedReturnValueMarker() const override {
     return "movl\t%ebp, %ebp"
-           "\t\t## marker for objc_retainAutoreleaseReturnValue";
+           "\t\t// marker for objc_retainAutoreleaseReturnValue";
   }
 };
 
 }
 
 /// Rewrite input constraint references after adding some output constraints.
 /// In the case where there is one output and one input and we add one output,
 /// we need to replace all operand references greater than or equal to 1:

 };
 
 class AArch64TargetCodeGenInfo : public TargetCodeGenInfo {
 public:
   AArch64TargetCodeGenInfo(CodeGenTypes &CGT, AArch64ABIInfo::ABIKind Kind)
       : TargetCodeGenInfo(new AArch64ABIInfo(CGT, Kind)) {}
 
   StringRef getARCRetainAutoreleasedReturnValueMarker() const override {
-    return "mov\tfp, fp\t\t# marker for objc_retainAutoreleaseReturnValue";
+    return "mov\tfp, fp\t\t// marker for objc_retainAutoreleaseReturnValue";
   }
 
   int getDwarfEHStackPointer(CodeGen::CodeGenModule &M) const override {
     return 31;
   }
 
   bool doesReturnSlotInterfereWithArgs() const override { return false; }
 };
const ARMABIInfo &getABIInfo() const {
     return static_cast<const ARMABIInfo&>(TargetCodeGenInfo::getABIInfo());
   }
 
   int getDwarfEHStackPointer(CodeGen::CodeGenModule &M) const override {
     return 13;
   }
 
   StringRef getARCRetainAutoreleasedReturnValueMarker() const override {
-    return "mov\tr7, r7\t\t@ marker for objc_retainAutoreleaseReturnValue";
+    return "mov\tr7, r7\t\t// marker for objc_retainAutoreleaseReturnValue";
   }
 
   bool initDwarfEHRegSizeTable(CodeGen::CodeGenFunction &CGF,
                                llvm::Value *Address) const override {
     llvm::Value *Four8 = llvm::ConstantInt::get(CGF.Int8Ty, 4);
 
     // 0-15 are the 16 integer registers.
     AssignToArrayRange(CGF.Builder, Address, Four8, 0, 15);

test/CodeGenObjC/arc-arm.m

 // RUN: %clang_cc1 -triple armv7-apple-darwin10 -emit-llvm -fblocks -fobjc-arc -o - %s | FileCheck %s
 // RUN: %clang_cc1 -triple arm64-apple-ios -emit-llvm -fblocks -fobjc-arc -o - %s | FileCheck %s
 
 // <rdar://12438598>: use an autorelease marker on ARM64.
 
 id test0(void) {
   extern id test0_helper(void);
   // CHECK:      [[T0:%.*]] = call [[CC:(arm_aapcscc )?]]i8* @test0_helper()
   // CHECK-NEXT: ret i8* [[T0]]
   return test0_helper();
 }
 
 void test1(void) {
   extern id test1_helper(void);
   // CHECK:      [[T0:%.*]] = call [[CC]]i8* @test1_helper()
-  // CHECK-NEXT: call void asm sideeffect "mov
+  // CHECK-NEXT: call void asm sideeffect "mov\09{{fp, fp|r7, r7}}\09\09// marker for objc_retainAutoreleaseReturnValue"
   // CHECK-NEXT: [[T1:%.*]] = call [[CC]]i8* @objc_retainAutoreleasedReturnValue(i8* [[T0]])
   // CHECK-NEXT: store i8* [[T1]],
   // CHECK-NEXT: call [[CC]]void @objc_storeStrong(
   // CHECK-NEXT: ret void
   id x = test1_helper();
 }
 
 // rdar://problem/12133032