Check vector elements for equivalence in the HexagonVectorLoopCarriedReuse pass

If the two instructions being compared for equivalence have corresponding operands
that are integer constants, then check their values to determine equivalence.

Patch by Suyog Sarda!

llvm-svn: 313993

1 files changed, 86 insertions, 0 deletions

diff --git a/llvm/test/CodeGen/Hexagon/hexagon_vector_loop_carried_reuse_constant.ll b/llvm/test/CodeGen/Hexagon/hexagon_vector_loop_carried_reuse_constant.ll
new file mode 100644
index 00000000000..3808364d41a
--- /dev/null
+++ b/llvm/test/CodeGen/Hexagon/hexagon_vector_loop_carried_reuse_constant.ll
@@ -0,0 +1,86 @@
+; RUN: opt < %s -hexagon-vlcr -adce -S | FileCheck %s
+
+; CHECK-NOT: %.hexagon.vlcr
+; ModuleID = 'hexagon_vector_loop_carried_reuse.c'
+source_filename = "hexagon_vector_loop_carried_reuse.c"
+target datalayout = "e-m:e-p:32:32:32-a:0-n16:32-i64:64:64-i32:32:32-i16:16:16-i1:8:8-f32:32:32-f64:64:64-v32:32:32-v64:64:64-v512:512:512-v1024:1024:1024-v2048:2048:2048"
+target triple = "hexagon"
+
+@W = external local_unnamed_addr global i32, align 4
+
+; Function Attrs: nounwind
+define void @foo(i8* noalias nocapture readonly %src, i8* noalias nocapture %dst, i32 %stride) local_unnamed_addr #0 {
+entry:
+  %add.ptr = getelementptr inbounds i8, i8* %src, i32 %stride
+  %mul = mul nsw i32 %stride, 2
+  %add.ptr1 = getelementptr inbounds i8, i8* %src, i32 %mul
+  %0 = load i32, i32* @W, align 4, !tbaa !1
+  %cmp55 = icmp sgt i32 %0, 0
+  br i1 %cmp55, label %for.body.lr.ph, label %for.end
+
+for.body.lr.ph:                                   ; preds = %entry
+  %1 = bitcast i8* %add.ptr1 to <32 x i32>*
+  %2 = load <32 x i32>, <32 x i32>* %1, align 128, !tbaa !5
+  %incdec.ptr4 = getelementptr inbounds i8, i8* %add.ptr1, i32 128
+  %3 = bitcast i8* %incdec.ptr4 to <32 x i32>*
+  %4 = bitcast i8* %add.ptr to <32 x i32>*
+  %5 = load <32 x i32>, <32 x i32>* %4, align 128, !tbaa !5
+  %incdec.ptr2 = getelementptr inbounds i8, i8* %add.ptr, i32 128
+  %6 = bitcast i8* %incdec.ptr2 to <32 x i32>*
+  %7 = bitcast i8* %src to <32 x i32>*
+  %8 = load <32 x i32>, <32 x i32>* %7, align 128, !tbaa !5
+  %incdec.ptr = getelementptr inbounds i8, i8* %src, i32 128
+  %9 = bitcast i8* %incdec.ptr to <32 x i32>*
+  %10 = bitcast i8* %dst to <32 x i32>*
+  br label %for.body
+
+for.body:                                         ; preds = %for.body.lr.ph, %for.body
+  %out.063 = phi <32 x i32>* [ %10, %for.body.lr.ph ], [ %incdec.ptr18, %for.body ]
+  %p2.062 = phi <32 x i32>* [ %3, %for.body.lr.ph ], [ %incdec.ptr10, %for.body ]
+  %p1.061 = phi <32 x i32>* [ %6, %for.body.lr.ph ], [ %incdec.ptr8, %for.body ]
+  %p0.060 = phi <32 x i32>* [ %9, %for.body.lr.ph ], [ %incdec.ptr6, %for.body ]
+  %i.059 = phi i32 [ 0, %for.body.lr.ph ], [ %add, %for.body ]
+  %a.sroa.0.058 = phi <32 x i32> [ %8, %for.body.lr.ph ], [ %11, %for.body ]
+  %b.sroa.0.057 = phi <32 x i32> [ %5, %for.body.lr.ph ], [ %12, %for.body ]
+  %c.sroa.0.056 = phi <32 x i32> [ %2, %for.body.lr.ph ], [ %13, %for.body ]
+  %incdec.ptr6 = getelementptr inbounds <32 x i32>, <32 x i32>* %p0.060, i32 1
+  %11 = load <32 x i32>, <32 x i32>* %p0.060, align 128, !tbaa !5
+  %incdec.ptr8 = getelementptr inbounds <32 x i32>, <32 x i32>* %p1.061, i32 1
+  %12 = load <32 x i32>, <32 x i32>* %p1.061, align 128, !tbaa !5
+  %incdec.ptr10 = getelementptr inbounds <32 x i32>, <32 x i32>* %p2.062, i32 1
+  %13 = load <32 x i32>, <32 x i32>* %p2.062, align 128, !tbaa !5
+  %14 = tail call <32 x i32> @llvm.hexagon.V6.valignbi.128B(<32 x i32> %a.sroa.0.058, <32 x i32> %b.sroa.0.057, i32 4)
+  %15 = tail call <32 x i32> @llvm.hexagon.V6.vmaxub.128B(<32 x i32> %14, <32 x i32> %c.sroa.0.056)
+  %16 = tail call <32 x i32> @llvm.hexagon.V6.valignbi.128B(<32 x i32> %11, <32 x i32> %12, i32 5)
+  %17 = tail call <32 x i32> @llvm.hexagon.V6.vmaxub.128B(<32 x i32> %16, <32 x i32> %13)
+  %18 = tail call <32 x i32> @llvm.hexagon.V6.valignbi.128B(<32 x i32> %17, <32 x i32> %15, i32 1)
+  %incdec.ptr18 = getelementptr inbounds <32 x i32>, <32 x i32>* %out.063, i32 1
+  store <32 x i32> %18, <32 x i32>* %out.063, align 128, !tbaa !5
+  %add = add nuw nsw i32 %i.059, 128
+  %cmp = icmp slt i32 %add, %0
+  br i1 %cmp, label %for.body, label %for.end.loopexit
+
+for.end.loopexit:                                 ; preds = %for.body
+  br label %for.end
+
+for.end:                                          ; preds = %for.end.loopexit, %entry
+  ret void
+}
+
+; Function Attrs: nounwind readnone
+declare <32 x i32> @llvm.hexagon.V6.vmaxub.128B(<32 x i32>, <32 x i32>) #1
+
+; Function Attrs: nounwind readnone
+declare <32 x i32> @llvm.hexagon.V6.valignbi.128B(<32 x i32>, <32 x i32>, i32) #1
+
+attributes #0 = { nounwind "correctly-rounded-divide-sqrt-fp-math"="false" "disable-tail-calls"="false" "less-precise-fpmad"="false" "no-frame-pointer-elim"="true" "no-frame-pointer-elim-non-leaf" "no-infs-fp-math"="false" "no-jump-tables"="false" "no-nans-fp-math"="false" "no-signed-zeros-fp-math"="false" "no-trapping-math"="false" "stack-protector-buffer-size"="8" "target-cpu"="hexagonv60" "target-features"="+hvx,+hvx-double,-long-calls" "unsafe-fp-math"="false" "use-soft-float"="false" }
+attributes #1 = { nounwind readnone }
+
+!llvm.ident = !{!0}
+
+!0 = !{!"QuIC LLVM Hexagon Clang version hexagon-clang-82-2622 (based on LLVM 5.0.0)"}
+!1 = !{!2, !2, i64 0}
+!2 = !{!"int", !3, i64 0}
+!3 = !{!"omnipotent char", !4, i64 0}
+!4 = !{!"Simple C/C++ TBAA"}
+!5 = !{!3, !3, i64 0}