[llvm] [MSan] Separated PPC32 va_arg helper from PPC64 (PR #131827)

[Vitaly Buka via llvm-commits]

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@@ -7,11 +7,11 @@ target triple = "powerpc--linux"
 define i32 @foo(i32 %guard, ...) {
 ; CHECK-LABEL: define i32 @foo(
 ; CHECK-SAME: i32 [[GUARD:%.*]], ...) {
-; CHECK-NEXT:    [[TMP2:%.*]] = load i64, ptr @__msan_va_arg_overflow_size_tls, align 8
-; CHECK-NEXT:    [[TMP3:%.*]] = alloca i8, i64 [[TMP2]], align 8
-; CHECK-NEXT:    call void @llvm.memset.p0.i64(ptr align 8 [[TMP3]], i8 0, i64 [[TMP2]], i1 false)
-; CHECK-NEXT:    [[TMP4:%.*]] = call i64 @llvm.umin.i64(i64 [[TMP2]], i64 800)
-; CHECK-NEXT:    call void @llvm.memcpy.p0.p0.i64(ptr align 8 [[TMP3]], ptr align 8 @__msan_va_arg_tls, i64 [[TMP4]], i1 false)
+; CHECK-NEXT:    [[TMP1:%.*]] = load i32, ptr @__msan_va_arg_overflow_size_tls, align 4
+; CHECK-NEXT:    [[TMP2:%.*]] = alloca i8, i32 [[TMP1]], align 8
+; CHECK-NEXT:    call void @llvm.memset.p0.i32(ptr align 8 [[TMP2]], i8 0, i32 [[TMP1]], i1 false)
+; CHECK-NEXT:    [[TMP3:%.*]] = call i32 @llvm.umin.i32(i32 [[TMP1]], i32 800)
+; CHECK-NEXT:    call void @llvm.memcpy.p0.p0.i32(ptr align 8 [[TMP2]], ptr align 8 @__msan_va_arg_tls, i32 [[TMP3]], i1 false)
 ; CHECK-NEXT:    call void @llvm.donothing()
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vitalybuka wrote:

Let's split this PR in 2:
1. NFC. Just fork PP32 unchanged
2. Change the behavior

https://github.com/llvm/llvm-project/pull/131827