[llvm] [RISCV] Allocate the varargs GPR save area as a single object. (PR #74354)

[Wang Pengcheng via llvm-commits]

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@@ -10,55 +10,59 @@ define void @va1arg(ptr %a, ...) {
   ; RV32-NEXT:   liveins: $x10, $x11, $x12, $x13, $x14, $x15, $x16, $x17
   ; RV32-NEXT: {{  $}}
   ; RV32-NEXT:   [[COPY:%[0-9]+]]:_(p0) = COPY $x10
+  ; RV32-NEXT:   [[FRAME_INDEX:%[0-9]+]]:_(p0) = G_FRAME_INDEX %fixed-stack.1
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wangpc-pp wrote:

Is this a regression or this can be optimized in later passes?

https://github.com/llvm/llvm-project/pull/74354