[PowerPC] MULHU/MULHS are not legal for vector types

I ran into some test failures where common code changed vector division
by constant into a multiply-high operation (MULHU).  But these are not
implemented by the back-end, so we failed to recognize the insn.

Fixed by marking MULHU/MULHS as Expand for vector types.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@214716 91177308-0d34-0410-b5e6-96231b3b80d8

diff --git a/lib/Target/PowerPC/PPCISelLowering.cpp b/lib/Target/PowerPC/PPCISelLowering.cpp
index a0f7256..bd74a09 100644 (file)
--- a/lib/Target/PowerPC/PPCISelLowering.cpp
+++ b/lib/Target/PowerPC/PPCISelLowering.cpp
@@ -453,6 +453,8 @@ PPCTargetLowering::PPCTargetLowering(PPCTargetMachine &TM)
       setOperationAction(ISD::EXTRACT_VECTOR_ELT, VT, Expand);
       setOperationAction(ISD::INSERT_VECTOR_ELT, VT, Expand);
       setOperationAction(ISD::BUILD_VECTOR, VT, Expand);
+      setOperationAction(ISD::MULHU, VT, Expand);
+      setOperationAction(ISD::MULHS, VT, Expand);
       setOperationAction(ISD::UMUL_LOHI, VT, Expand);
       setOperationAction(ISD::SMUL_LOHI, VT, Expand);
       setOperationAction(ISD::UDIVREM, VT, Expand);

diff --git a/test/CodeGen/PowerPC/vec_urem_const.ll b/test/CodeGen/PowerPC/vec_urem_const.ll
new file mode 100644 (file)
index 0000000..a562c3b
--- /dev/null
+++ b/test/CodeGen/PowerPC/vec_urem_const.ll
@@ -0,0 +1,10 @@
+; RUN: llc -mcpu=pwr6 -mattr=+altivec < %s
+
+; Common code used to replace the urem by a mulhu, and compilation would
+; then crash since mulhu isn't supported on vector types.
+
+define <4 x i32> @test(<4 x i32> %x) {
+entry:
+  %0 = urem <4 x i32> %x, <i32 2147483647, i32 2147483647, i32 2147483647, i32 2147483647>
+  ret <4 x i32> %0
+}