[PATCH] D18890: [AArch64] add SSA Load Store optimization pass

[Jun Bum Lim via llvm-commits]

junbuml added a comment.

The change specifically handle two consecutive loads / stores widening in SSA form. I'm not sure if this is a good motivating use case to add a new pass. Did you see any performance gain with this change?


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Comment at: test/CodeGen/AArch64/ssa-ldst-opt.ll:9-13
@@ +8,7 @@
+  %ld.ptr1 = getelementptr i32, i32* %p1, i64 -19
+  %1 = load i32, i32* %ld.ptr1, align 4
+  %st.ptr1 = getelementptr i32, i32* %p2, i64 -11
+  store i32 %1, i32* %st.ptr1, align 4
+  %ld.ptr2 = getelementptr i32, i32* %p1, i64 -18
+  %2 = load i32, i32* %ld.ptr2, align 4
+  %st.ptr2 = getelementptr i32, i32* %p2, i64 -10
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Merging the second load to the first load seems to be wrong without alias check between the second load and the first store.


http://reviews.llvm.org/D18890