[llvm] [PowerPC] fix legalization crash (PR #105563)

[Chen Zheng via llvm-commits]

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@@ -0,0 +1,60 @@
+; NOTE: Assertions have been autogenerated by utils/update_llc_test_checks.py UTC_ARGS: --version 5
+; RUN: llc -verify-machineinstrs < %s | FileCheck %s
+
+target datalayout = "E-m:e-Fi64-i64:64-n32:64-S128-v256:256:256-v512:512:512"
+target triple = "powerpc64-unknown-linux-gnu"
+
+define void @_blah() #0 {
+; CHECK-LABEL: _blah:
+; CHECK:       # %bb.0: # %entry
+; CHECK-NEXT:    li 3, 0
+; CHECK-NEXT:    li 4, 15
+; CHECK-NEXT:    lvx 3, 0, 4
+; CHECK-NEXT:    addi 5, 1, -64
+; CHECK-NEXT:    lvx 4, 0, 3
+; CHECK-NEXT:    lvsl 2, 0, 3
+; CHECK-NEXT:    vperm 2, 4, 3, 2
+; CHECK-NEXT:    lwz 4, 16(0)
+; CHECK-NEXT:    stvx 2, 0, 5
+; CHECK-NEXT:    lhz 5, -64(1)
+; CHECK-NEXT:    lhz 6, -58(1)
+; CHECK-NEXT:    lhz 7, -52(1)
+; CHECK-NEXT:    sth 4, -34(1)
+; CHECK-NEXT:    sth 3, -36(1)
+; CHECK-NEXT:    sth 3, -40(1)
+; CHECK-NEXT:    sth 3, -44(1)
+; CHECK-NEXT:    sth 3, -48(1)
+; CHECK-NEXT:    addi 3, 1, -48
+; CHECK-NEXT:    sth 7, -38(1)
+; CHECK-NEXT:    sth 6, -42(1)
+; CHECK-NEXT:    sth 5, -46(1)
+; CHECK-NEXT:    lvx 2, 0, 3
+; CHECK-NEXT:    addi 3, 1, -32
+; CHECK-NEXT:    vsldoi 3, 2, 2, 8
+; CHECK-NEXT:    vmaxuw 2, 2, 3
+; CHECK-NEXT:    vspltw 3, 2, 1
+; CHECK-NEXT:    vmaxuw 2, 2, 3
+; CHECK-NEXT:    stvx 2, 0, 3
+; CHECK-NEXT:    lwz 3, -32(1)
+; CHECK-NEXT:    cmplwi 3, 0
+; CHECK-NEXT:    blr
+entry:
+  %wide.vec904 = load <12 x i16>, ptr null, align 2
+  %strided.vec905 = shufflevector <12 x i16> %wide.vec904, <12 x i16> zeroinitializer, <4 x i32> <i32 0, i32 3, i32 6, i32 9>
+  %0 = zext <4 x i16> %strided.vec905 to <4 x i32>
+  %1 = tail call i32 @llvm.vector.reduce.umax.v4i32(<4 x i32> %0)
+  %cmp55.not823 = icmp ugt i32 1, %1
+  br i1 %cmp55.not823, label %for.cond.cleanup56, label %for.body57.lr.ph
+
+for.body57.lr.ph:                                 ; preds = %entry
+  ret void
+
+for.cond.cleanup56:                               ; preds = %entry
+  ret void
+}
+
+; Function Attrs: nocallback nofree nosync nounwind speculatable willreturn memory(none)
+declare i32 @llvm.vector.reduce.umax.v4i32(<4 x i32>) #1
+
+attributes #0 = { "target-cpu"="ppc64" }
+attributes #1 = { nocallback nofree nosync nounwind speculatable willreturn memory(none) }
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chenzheng1030 wrote:

nit: it this necessary to reproduce this crash?

https://github.com/llvm/llvm-project/pull/105563