6502/llvm-6502
1
0
Fork 0
mirror of https://github.com/c64scene-ar/llvm-6502.git synced 2024-08-17 21:29:20 +00:00
Code Issues Projects Releases Wiki Activity

Add a note about a potential PIC optimization.

Browse Source 
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@52663 91177308-0d34-0410-b5e6-96231b3b80d8
This commit is contained in:
Dan Gohman 2008-06-24 00:53:07 +00:00
parent db7991de75
commit 2d0d59380a
1 changed files with 7 additions and 0 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

7
lib/Target/X86/README.txt
View File

@ -1709,3 +1709,10 @@ _test:
it would be better to codegen as: x+~y (notl+addl)
//===---------------------------------------------------------------------===//
We should consider using __i686.get_pc_thunk.bx for MOVPC32r (used for PIC)
on targets that support it, such as Linux and similar targets, in place of
the call-a-label trick. It's said to be friendlier to branch-prediction
hardware because it pairs a ret with the call.
//===---------------------------------------------------------------------===//