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to find opportunities for store-to-load forwarding or load CSE, in the same way that visitStore scans back to do DSE. Also, define a new helper function for testing whether the addresses of two memory accesses are known to have the same value, and use it in both visitStore and visitLoad. These two changes allow instcombine to eliminate loads in code produced by front-ends that frequently emit obviously redundant addressing for memory references. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@57608 91177308-0d34-0410-b5e6-96231b3b80d8
15 lines
388 B
LLVM
15 lines
388 B
LLVM
; RUN: llvm-as < %s | opt -instcombine | llvm-dis | grep load | count 1
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; Instcombine should be able to do trivial CSE of loads.
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declare void @use(double %n)
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define void @bar(double* %p) {
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%t0 = getelementptr double* %p, i32 1
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%y = load double* %t0
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%t1 = getelementptr double* %p, i32 1
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%x = load double* %t1
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call void @use(double %x)
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call void @use(double %y)
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ret void
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}
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