[PowerPC] fix legalization crash

llvm/lib/Target/PowerPC/PPCISelLowering.cpp

@@ -12032,6 +12032,12 @@ void PPCTargetLowering::ReplaceNodeResults(SDNode *N,
       Results.push_back(Lowered);
     return;
   }
+  case ISD::SCALAR_TO_VECTOR: {
+    SDValue Lowered = LowerSCALAR_TO_VECTOR(SDValue(N, 0), DAG);
+    if (Lowered)
+      Results.push_back(Lowered);
+    return;
+  }
   case ISD::FSHL:
   case ISD::FSHR:
     // Don't handle funnel shifts here.

llvm/test/CodeGen/PowerPC/custom-stov.ll

@@ -0,0 +1,55 @@
+; NOTE: Assertions have been autogenerated by utils/update_llc_test_checks.py UTC_ARGS: --version 5
+; RUN: llc -mcpu=ppc64 -mtriple=powerpc64-unknown-linux-gnu \
+; RUN:     -verify-machineinstrs -ppc-asm-full-reg-names -ppc-vsr-nums-as-vr \
+; RUN:     < %s | FileCheck %s
+
+define void @_blah() {
+; CHECK-LABEL: _blah:
+; CHECK:       # %bb.0: # %entry
+; CHECK-NEXT:    li r3, 0
+; CHECK-NEXT:    li r4, 15
+; CHECK-NEXT:    lvx v3, 0, r4
+; CHECK-NEXT:    addi r5, r1, -64
+; CHECK-NEXT:    lvx v4, 0, r3
+; CHECK-NEXT:    lvsl v2, 0, r3
+; CHECK-NEXT:    vperm v2, v4, v3, v2
+; CHECK-NEXT:    lwz r4, 16(0)
+; CHECK-NEXT:    stvx v2, 0, r5
+; CHECK-NEXT:    lhz r5, -64(r1)
+; CHECK-NEXT:    lhz r6, -58(r1)
+; CHECK-NEXT:    lhz r7, -52(r1)
+; CHECK-NEXT:    sth r4, -34(r1)
+; CHECK-NEXT:    sth r3, -36(r1)
+; CHECK-NEXT:    sth r3, -40(r1)
+; CHECK-NEXT:    sth r3, -44(r1)
+; CHECK-NEXT:    sth r3, -48(r1)
+; CHECK-NEXT:    addi r3, r1, -48
+; CHECK-NEXT:    sth r7, -38(r1)
+; CHECK-NEXT:    sth r6, -42(r1)
+; CHECK-NEXT:    sth r5, -46(r1)
+; CHECK-NEXT:    lvx v2, 0, r3
+; CHECK-NEXT:    addi r3, r1, -32
+; CHECK-NEXT:    vsldoi v3, v2, v2, 8
+; CHECK-NEXT:    vmaxuw v2, v2, v3
+; CHECK-NEXT:    vspltw v3, v2, 1
+; CHECK-NEXT:    vmaxuw v2, v2, v3
+; CHECK-NEXT:    stvx v2, 0, r3
+; CHECK-NEXT:    lwz r3, -32(r1)
+; CHECK-NEXT:    cmplwi r3, 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
+}
+
+declare i32 @llvm.vector.reduce.umax.v4i32(<4 x i32>)