[llvm] [RISCV] Sources of vmerge shouldn't overlap V0 (PR #170070)

[Pengcheng Wang via llvm-commits]

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@@ -1874,57 +1874,77 @@ define float @vreduce_fminimum_v128f32(ptr %x) {
 ; CHECK-NEXT:    addi sp, sp, -16
 ; CHECK-NEXT:    .cfi_def_cfa_offset 16
 ; CHECK-NEXT:    csrr a1, vlenb
-; CHECK-NEXT:    slli a1, a1, 4
+; CHECK-NEXT:    slli a1, a1, 3
+; CHECK-NEXT:    mv a2, a1
+; CHECK-NEXT:    slli a1, a1, 1
+; CHECK-NEXT:    add a1, a1, a2
 ; CHECK-NEXT:    sub sp, sp, a1
-; CHECK-NEXT:    .cfi_escape 0x0f, 0x0d, 0x72, 0x00, 0x11, 0x10, 0x22, 0x11, 0x10, 0x92, 0xa2, 0x38, 0x00, 0x1e, 0x22 # sp + 16 + 16 * vlenb
+; CHECK-NEXT:    .cfi_escape 0x0f, 0x0d, 0x72, 0x00, 0x11, 0x10, 0x22, 0x11, 0x18, 0x92, 0xa2, 0x38, 0x00, 0x1e, 0x22 # sp + 16 + 24 * vlenb
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wangpc-pp wrote:

This is a regression.

https://github.com/llvm/llvm-project/pull/170070