[llvm-commits] [llvm] r62144 - in /llvm/trunk: lib/CodeGen/SimpleRegisterCoalescing.cpp test/CodeGen/X86/2009-01-12-CoalescerBug.ll

[Duncan Sands]

Hi Evan,

> FIX llvm-gcc bootstrap on x86_64 linux. If a virtual register is copied to a physical register, it's not necessarily defined by a copy. We have to watch out it doesn't clobber any sub-register that might be live during its live interval. If the live interval crosses a basic block, then it's not safe to check with the less conservative check (by scanning uses and defs) because it's possible a sub-register might be live out of the block.

thanks for fixing this.  I don't know how you managed to work out what
was going wrong - maybe your spider-sense helped :)

Ciao,

Duncan.