llvm-6502

mirror of https://github.com/c64scene-ar/llvm-6502.git synced 2025-03-01 01:30:36 +00:00

History

Chris Lattner 2ad913b342 Disable the (A == (B-A)) -> 2*A == B xform when the sub has multiple uses (in

this case, the xform introduces an extra operation).  This compiles
PowerPC/compare-duplicate.ll into:

_test:
        subf r2, r3, r4
        cmplw cr0, r2, r3
        bne cr0, LBB1_2 ;F

instead of:

_test:
        slwi r2, r3, 1
        subf r3, r3, r4
        cmplw cr0, r4, r2
        bne cr0, LBB1_2 ;F

This is target independent of course.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@37246 91177308-0d34-0410-b5e6-96231b3b80d8

2007-05-19 00:43:44 +00:00

Analysis

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