MSVC: Re-enable alignment attribute for sret params

Seems to be working with recent LLVM - at least for x64.

Author: kinke

gen/functions.cpp

@@ -79,12 +79,8 @@ llvm::FunctionType *DtoFunctionType(Type *type, IrFuncTy &irFty, Type *thistype,
       newIrFty.arg_sret = new IrFuncTyArg(
           rt, true,
           AttrBuilder().add(LLAttribute::StructRet).add(LLAttribute::NoAlias));
-      const unsigned alignment = DtoAlignment(rt);
-      if (alignment &&
-          // FIXME: LLVM inliner issues for std.bitmanip and std.uni on Win64
-          !global.params.targetTriple->isOSMSVCRT()) {
+      if (unsigned alignment = DtoAlignment(rt))
         newIrFty.arg_sret->attrs.addAlignment(alignment);
-      }
       rt = Type::tvoid;
       ++nextLLArgIdx;
     } else {

tests/codegen/align.d

@@ -10,14 +10,13 @@ static Inner globalInner;
 
 Outer passAndReturnOuterByVal(Outer arg) { return arg; }
 // CHECK: define{{.*}} void @{{.*}}_D5align23passAndReturnOuterByValFS5align5OuterZS5align5Outer
-/* no sret align attributes for MSVC targets at the moment */
-// C HECK-SAME: %align.Outer* noalias sret align 32 %.sret_arg
+// CHECK-SAME: %align.Outer* noalias sret align 32 %.sret_arg
 /* how the arg is passed by value is ABI-specific, but the pointer must be aligned */
 // CHECK-SAME: align 32 %
 
 Inner passAndReturnInnerByVal(Inner arg) { return arg; }
 // CHECK: define{{.*}} void @{{.*}}_D5align23passAndReturnInnerByValFS5align5InnerZS5align5Inner
-// C HECK-SAME: %align.Inner* noalias sret align 32 %.sret_arg
+// CHECK-SAME: %align.Inner* noalias sret align 32 %.sret_arg
 // CHECK-SAME: align 32 %
 
 void main() {
@@ -49,11 +48,11 @@ void main() {
 
   outer = passAndReturnOuterByVal(outer);
   // CHECK: call{{.*}} void @{{.*}}_D5align23passAndReturnOuterByValFS5align5OuterZS5align5Outer
-  // C HECK-SAME: %align.Outer* noalias sret align 32 %.rettmp
+  // CHECK-SAME: %align.Outer* noalias sret align 32 %.rettmp
   // CHECK-SAME: align 32 %
 
   inner = passAndReturnInnerByVal(inner);
   // CHECK: call{{.*}} void @{{.*}}_D5align23passAndReturnInnerByValFS5align5InnerZS5align5Inner
-  // C HECK-SAME: %align.Inner* noalias sret align 32 %.rettmp1
+  // CHECK-SAME: %align.Inner* noalias sret align 32 %.rettmp1
   // CHECK-SAME: align 32 %
 }