[clang] [llvm] [PowerPC][AIX] Specify correct ABI alignment for double (PR #144673)

[Sean Fertile via llvm-commits]

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@@ -96,16 +96,16 @@ define double @double_va_arg(double %a, ...) local_unnamed_addr  {
 ; CHECK-LABEL: double_va_arg:
 ; CHECK:       # %bb.0: # %entry
 ; CHECK-NEXT:    addi 3, 1, 56
-; CHECK-NEXT:    std 4, 56(1)
-; CHECK-NEXT:    std 3, -8(1)
+; CHECK-NEXT:    lfd 0, 56(1)
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mandlebug wrote:

It looks like this change is exposing an issue related to var-args. We schedule this load from the stack before the arguments are spilled into the va_list. I'm investigating the difference to figure out why this is happening now.

https://github.com/llvm/llvm-project/pull/144673