[PATCH] D18336: Prevent construction of cycle in DAG store merge

[Yin Ma via llvm-commits]

yinma added inline comments.

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Comment at: lib/CodeGen/SelectionDAG/DAGCombiner.cpp:11184
@@ +11183,3 @@
+  if (UseAA){
+    // Any pair of candidates here may cause a problem, but as all
+    // stores are on parallel chains so in the correct case, none of
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if UseAA creates a different but broader case. we should try to merge testing with UseAA and without UsaAA to be one testing.

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Comment at: test/CodeGen/AArch64/vector_merge_dep_check.ll:11
@@ +10,3 @@
+define void @_ZN5Eigen8internal13gemm_pack_rhsINSt3__17complexIfEElLi2ELi0ELb0ELb1EEclEPS4_PKS4_lllll(<2 x i64>* %argA, <2 x i64>* %argB) #0 align 2 {
+entry:
+  br i1 undef, label %polly.loop_header134, label %polly.cond184
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My code is reduced by bugpoint, The idea is shown exactly in your suggestion.


http://reviews.llvm.org/D18336