SLPVectorize: Replace the code that checks for vectorization candidates in successor blocks with code that scans PHINodes.

Before we could vectorize PHINodes scanning successors was a good way of finding candidates. Now we can vectorize the phinodes which is simpler.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@186139 91177308-0d34-0410-b5e6-96231b3b80d8

1 files changed, 74 insertions, 0 deletions

diff --git a/test/Transforms/SLPVectorizer/X86/rgb_phi.ll b/test/Transforms/SLPVectorizer/X86/rgb_phi.ll
new file mode 100644
index 0000000..6a92435
--- /dev/null
+++ b/test/Transforms/SLPVectorizer/X86/rgb_phi.ll
@@ -0,0 +1,74 @@
+; RUN: opt < %s -basicaa -slp-vectorizer -dce -S -mtriple=i386-apple-macosx10.8.0 -mcpu=corei7-avx | FileCheck %s
+
+target datalayout = "e-p:32:32:32-i1:8:8-i8:8:8-i16:16:16-i32:32:32-i64:32:64-f32:32:32-f64:32:64-v64:64:64-v128:128:128-a0:0:64-f80:128:128-n8:16:32-S128"
+target triple = "i386-apple-macosx10.9.0"
+
+; float foo(float *A) {
+;
+;   float R = A[0];
+;   float G = A[1];
+;   float B = A[2];
+;   for (int i=0; i < 121; i+=3) {
+;     R+=A[i+0]*7;
+;     G+=A[i+1]*8;
+;     B+=A[i+2]*9;
+;   }
+;
+;   return R+G+B;
+; }
+
+;CHECK: @foo
+;CHECK: br
+;CHECK: phi <3 x float>
+;CHECK: fmul <3 x float>
+;CHECK: fadd <3 x float>
+; At the moment we don't sink extractelements.
+;CHECK: extractelement
+;CHECK: extractelement
+;CHECK: extractelement
+;CHECK: br
+;CHECK: ret
+
+define float @foo(float* nocapture readonly %A) {
+entry:
+  %0 = load float* %A, align 4
+  %arrayidx1 = getelementptr inbounds float* %A, i64 1
+  %1 = load float* %arrayidx1, align 4
+  %arrayidx2 = getelementptr inbounds float* %A, i64 2
+  %2 = load float* %arrayidx2, align 4
+  br label %for.body
+
+for.body:                                         ; preds = %for.body.for.body_crit_edge, %entry
+  %3 = phi float [ %0, %entry ], [ %.pre, %for.body.for.body_crit_edge ]
+  %indvars.iv = phi i64 [ 0, %entry ], [ %indvars.iv.next, %for.body.for.body_crit_edge ]
+  %B.032 = phi float [ %2, %entry ], [ %add14, %for.body.for.body_crit_edge ]
+  %G.031 = phi float [ %1, %entry ], [ %add9, %for.body.for.body_crit_edge ]
+  %R.030 = phi float [ %0, %entry ], [ %add4, %for.body.for.body_crit_edge ]
+  %mul = fmul float %3, 7.000000e+00
+  %add4 = fadd float %R.030, %mul
+  %4 = add nsw i64 %indvars.iv, 1
+  %arrayidx7 = getelementptr inbounds float* %A, i64 %4
+  %5 = load float* %arrayidx7, align 4
+  %mul8 = fmul float %5, 8.000000e+00
+  %add9 = fadd float %G.031, %mul8
+  %6 = add nsw i64 %indvars.iv, 2
+  %arrayidx12 = getelementptr inbounds float* %A, i64 %6
+  %7 = load float* %arrayidx12, align 4
+  %mul13 = fmul float %7, 9.000000e+00
+  %add14 = fadd float %B.032, %mul13
+  %indvars.iv.next = add i64 %indvars.iv, 3
+  %8 = trunc i64 %indvars.iv.next to i32
+  %cmp = icmp slt i32 %8, 121
+  br i1 %cmp, label %for.body.for.body_crit_edge, label %for.end
+
+for.body.for.body_crit_edge:                      ; preds = %for.body
+  %arrayidx3.phi.trans.insert = getelementptr inbounds float* %A, i64 %indvars.iv.next
+  %.pre = load float* %arrayidx3.phi.trans.insert, align 4
+  br label %for.body
+
+for.end:                                          ; preds = %for.body
+  %add16 = fadd float %add4, %add9
+  %add17 = fadd float %add16, %add14
+  ret float %add17
+}
+