Index: llvm/trunk/lib/Target/PowerPC/PPCISelLowering.cpp
===================================================================
--- llvm/trunk/lib/Target/PowerPC/PPCISelLowering.cpp
+++ llvm/trunk/lib/Target/PowerPC/PPCISelLowering.cpp
@@ -11996,10 +11996,15 @@
   auto isSExtOfVecExtract = [&](SDValue Op) -> bool {
     if (!Op)
       return false;
-    if (Op.getOpcode() != ISD::SIGN_EXTEND)
+    if (Op.getOpcode() != ISD::SIGN_EXTEND &&
+        Op.getOpcode() != ISD::SIGN_EXTEND_INREG)
       return false;
 
+    // A SIGN_EXTEND_INREG might be fed by an ANY_EXTEND to produce a value
+    // of the right width.
     SDValue Extract = Op.getOperand(0);
+    if (Extract.getOpcode() == ISD::ANY_EXTEND)
+      Extract = Extract.getOperand(0);
     if (Extract.getOpcode() != ISD::EXTRACT_VECTOR_ELT)
       return false;
 
@@ -12087,8 +12092,10 @@
     return Reduced;
 
   // If we're building a vector out of extended elements from another vector
-  // we have P9 vector integer extend instructions.
-  if (Subtarget.hasP9Altivec()) {
+  // we have P9 vector integer extend instructions. The code assumes legal
+  // input types (i.e. it can't handle things like v4i16) so do not run before
+  // legalization.
+  if (Subtarget.hasP9Altivec() && !DCI.isBeforeLegalize()) {
     Reduced = combineBVOfVecSExt(N, DAG);
     if (Reduced)
       return Reduced;
Index: llvm/trunk/test/CodeGen/PowerPC/pr38087.ll
===================================================================
--- llvm/trunk/test/CodeGen/PowerPC/pr38087.ll
+++ llvm/trunk/test/CodeGen/PowerPC/pr38087.ll
@@ -0,0 +1,55 @@
+; NOTE: Assertions have been autogenerated by utils/update_llc_test_checks.py
+; RUN: llc -verify-machineinstrs -mcpu=pwr9 -ppc-vsr-nums-as-vr \
+; RUN:   -mtriple=powerpc64le-unknown-unknown -ppc-asm-full-reg-names < %s | \
+; RUN:   FileCheck %s
+; Function Attrs: nounwind readnone speculatable
+declare <4 x float> @llvm.fmuladd.v4f32(<4 x float>, <4 x float>, <4 x float>) #0
+
+; Function Attrs: nounwind readnone speculatable
+declare { i32, i1 } @llvm.usub.with.overflow.i32(i32, i32) #0
+
+define void @draw_llvm_vs_variant0() {
+; CHECK-LABEL: draw_llvm_vs_variant0:
+; CHECK:       # %bb.0: # %entry
+; CHECK-NEXT:    lfd f0, 0(r3)
+; CHECK-NEXT:    xxpermdi v2, f0, f0, 2
+; CHECK-NEXT:    vmrglh v2, v2, v2
+; CHECK-NEXT:    vextsh2w v2, v2
+; CHECK-NEXT:    xvcvsxwsp vs0, v2
+; CHECK-NEXT:    xxspltw vs0, vs0, 2
+; CHECK-NEXT:    xvmaddasp vs0, vs0, vs0
+; CHECK-NEXT:    stxvx vs0, 0, r3
+; CHECK-NEXT:    blr
+entry:
+  %.size = load i32, i32* undef
+  %0 = call { i32, i1 } @llvm.usub.with.overflow.i32(i32 %.size, i32 7)
+  %1 = extractvalue { i32, i1 } %0, 0
+  %2 = call { i32, i1 } @llvm.usub.with.overflow.i32(i32 %1, i32 0)
+  %3 = extractvalue { i32, i1 } %2, 0
+  %4 = select i1 false, i32 0, i32 %3
+  %5 = xor i1 false, true
+  %6 = sext i1 %5 to i32
+  %7 = load <4 x i16>, <4 x i16>* undef, align 2
+  %8 = extractelement <4 x i16> %7, i32 0
+  %9 = sext i16 %8 to i32
+  %10 = insertelement <4 x i32> undef, i32 %9, i32 0
+  %11 = extractelement <4 x i16> %7, i32 1
+  %12 = sext i16 %11 to i32
+  %13 = insertelement <4 x i32> %10, i32 %12, i32 1
+  %14 = extractelement <4 x i16> %7, i32 2
+  %15 = sext i16 %14 to i32
+  %16 = insertelement <4 x i32> %13, i32 %15, i32 2
+  %17 = extractelement <4 x i16> %7, i32 3
+  %18 = sext i16 %17 to i32
+  %19 = insertelement <4 x i32> %16, i32 %18, i32 3
+  %20 = sitofp <4 x i32> %19 to <4 x float>
+  %21 = insertelement <4 x i32> undef, i32 %6, i32 0
+  %22 = shufflevector <4 x i32> %21, <4 x i32> undef, <4 x i32> zeroinitializer
+  %23 = bitcast <4 x float> %20 to <4 x i32>
+  %24 = and <4 x i32> %23, %22
+  %25 = bitcast <4 x i32> %24 to <4 x float>
+  %26 = shufflevector <4 x float> %25, <4 x float> undef, <4 x i32> <i32 1, i32 1, i32 1, i32 1>
+  %27 = call <4 x float> @llvm.fmuladd.v4f32(<4 x float> undef, <4 x float> undef, <4 x float> %26)
+  store <4 x float> %27, <4 x float>* undef
+  ret void
+}