[llvm] [PPC]Optimize zeroing accumulator and spilling instructions into simple instructions (PR #96094)

[Chen Zheng via llvm-commits]

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@@ -115,22 +115,20 @@ declare <512 x i1> @llvm.ppc.mma.xxsetaccz()
 define void @int_xxsetaccz(ptr %ptr) {
 ; CHECK-LABEL: int_xxsetaccz:
 ; CHECK:       # %bb.0: # %entry
-; CHECK-NEXT:    xxsetaccz acc0
-; CHECK-NEXT:    xxmfacc acc0
+; CHECK-NEXT:    xxlxor vs0, vs0, vs0
 ; CHECK-NEXT:    stxv vs0, 48(r3)
-; CHECK-NEXT:    stxv vs1, 32(r3)
-; CHECK-NEXT:    stxv vs2, 16(r3)
-; CHECK-NEXT:    stxv vs3, 0(r3)
+; CHECK-NEXT:    stxv vs0, 32(r3)
+; CHECK-NEXT:    stxv vs0, 16(r3)
+; CHECK-NEXT:    stxv vs0, 0(r3)
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chenzheng1030 wrote:

Not related to this patch, the case at line 50 seems like an existing bug...

https://github.com/llvm/llvm-project/pull/96094