llvm-6502

mirror of https://github.com/c64scene-ar/llvm-6502.git synced 2025-02-14 17:34:41 +00:00

History

Devang Patel cf4cc84738 During post RA scheduling, do not try to chase reg defs. to preserve DBG_VALUEs. This approach has several downsides, for example, it does not work when dbg value is a constant integer, it does not work if reg is defined more than once, it places end of debug value range markers in the wrong place. It even causes misleading incorrect debug info when duplicate DBG_VALUE instructions point to same reg def.

Instead, use simpler approach and let DBG_VALUE follow its predecessor instruction. After live debug value analysis pass, all DBG_VALUE instruction are placed at the right place. Thanks Jakob for the hint!


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@132483 91177308-0d34-0410-b5e6-96231b3b80d8

2011-06-02 20:07:12 +00:00

Analysis

When marking a block as being unanalyzable, use "Clobber" on the terminator instead of the first instruction in the block. This is a bit of a hack; "Clobber" isn't really the right marking in the first place. memdep doesn't really have any way of properly expressing "unanalyzable" at the moment. Using it on the terminator is much less ambiguous than using it on an arbitrary instruction, though.

2011-06-02 00:08:52 +00:00