SLPVectorizer: Only vectorize intrinsics whose operands are widened equally

The vectorizer only knows how to vectorize intrinics by widening all operands by
the same factor.

Patch by Tyler Nowicki!

llvm-svn: 205855

1 files changed, 36 insertions, 0 deletions

diff --git a/llvm/test/Transforms/SLPVectorizer/X86/non-vectorizable-intrinsic.ll b/llvm/test/Transforms/SLPVectorizer/X86/non-vectorizable-intrinsic.ll
new file mode 100644
index 00000000000..b250735874c
--- /dev/null
+++ b/llvm/test/Transforms/SLPVectorizer/X86/non-vectorizable-intrinsic.ll
@@ -0,0 +1,36 @@
+; RUN: opt < %s -slp-vectorizer -o - -S -slp-threshold=-1000
+
+target datalayout = "e-p:32:32-i64:64-v16:16-v32:32-n16:32:64"
+target triple = "nvptx--nvidiacl"
+
+; CTLZ cannot be vectorized currently because the second argument is a scalar
+; for both the scalar and vector forms of the intrinsic. In the future it
+; should be possible to vectorize such functions.
+; Test causes an assert if LLVM tries to vectorize CTLZ.
+
+define <2 x i8> @cltz_test(<2 x i8> %x) #0 {
+entry:
+  %0 = extractelement <2 x i8> %x, i32 0
+  %call.i = call i8 @llvm.ctlz.i8(i8 %0, i1 false)
+  %vecinit = insertelement <2 x i8> undef, i8 %call.i, i32 0
+  %1 = extractelement <2 x i8> %x, i32 1
+  %call.i4 = call i8 @llvm.ctlz.i8(i8 %1, i1 false)
+  %vecinit2 = insertelement <2 x i8> %vecinit, i8 %call.i4, i32 1
+  ret <2 x i8> %vecinit2
+}
+
+define <2 x i8> @cltz_test2(<2 x i8> %x) #1 {
+entry:
+  %0 = extractelement <2 x i8> %x, i32 0
+  %1 = extractelement <2 x i8> %x, i32 1
+  %call.i = call i8 @llvm.ctlz.i8(i8 %0, i1 false)
+  %call.i4 = call i8 @llvm.ctlz.i8(i8 %1, i1 false)
+  %vecinit = insertelement <2 x i8> undef, i8 %call.i, i32 0
+  %vecinit2 = insertelement <2 x i8> %vecinit, i8 %call.i4, i32 1
+  ret <2 x i8> %vecinit2
+}
+
+declare i8 @llvm.ctlz.i8(i8, i1) #3
+
+attributes #0 = { alwaysinline nounwind "less-precise-fpmad"="false" "no-frame-pointer-elim"="true" "no-frame-pointer-elim-non-leaf" "no-infs-fp-math"="false" "no-nans-fp-math"="false" "stack-protector-buffer-size"="8" "unsafe-fp-math"="false" "use-soft-float"="false" }
+attributes #1 = { nounwind readnone }