[clang] Switch DirectX Target to use the Itanium ABI (PR #111632)

[Greg Roth via cfe-commits]

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@@ -260,10 +260,10 @@ void order_matters(inout int X, inout int Y) {
 // CHECK: store i32 [[VVal]], ptr [[Tmp0]]
 // CHECK: [[VVal:%.*]] = load i32, ptr [[V]]
 // CHECK: store i32 [[VVal]], ptr [[Tmp1]]
-// CHECK: call void {{.*}}order_matters{{.*}}(ptr noalias noundef nonnull align 4 dereferenceable(4) [[Tmp1]], ptr noalias noundef nonnull align 4 dereferenceable(4) [[Tmp0]])
-// CHECK: [[Arg1Val:%.*]] = load i32, ptr [[Tmp1]]
+// CHECK: call void {{.*}}order_matters{{.*}}(ptr noalias noundef nonnull align 4 dereferenceable(4) [[Tmp0]], ptr noalias noundef nonnull align 4 dereferenceable(4) [[Tmp1]])
+// CHECK: [[Arg1Val:%.*]] = load i32, ptr [[Tmp0]]
 // CHECK: store i32 [[Arg1Val]], ptr [[V]]
-// CHECK: [[Arg2Val:%.*]] = load i32, ptr [[Tmp0]]
+// CHECK: [[Arg2Val:%.*]] = load i32, ptr [[Tmp1]]
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pow2clk wrote:

This is where the order of copy in copy out is reflected

https://github.com/llvm/llvm-project/pull/111632