6502/llvm-6502
1
0
Fork 0
mirror of https://github.com/c64scene-ar/llvm-6502.git synced 2025-01-08 03:30:22 +00:00
Code Issues Projects Releases Wiki Activity
LLVM backend for 6502
43,752 Commits 39 Branches 0 Tags 277 MiB
C++ 48.7%
LLVM 38.5%
Assembly 10.2%
C 0.9%
Python 0.4%
Other 1.2%
8f90b6eb2f
Go to file
Evan Cheng 8f90b6eb2f The coalescer does not coalesce a virtual register to a physical register if any of the physical register's sub-register live intervals overlaps with the virtual register. This is overly conservative. It prevents a extract_subreg from being coalesced away: 
v1024 = EDI  // not killed
      =
      = EDI

One possible solution is for the coalescer to examine the sub-register live intervals in the same manner as the physical register. Another possibility is to examine defs and uses (when needed) of sub-registers. Both solutions are too expensive. For now, look for "short virtual intervals" and scan instructions to look for conflict instead.

This is a small win on x86-64. e.g. It shaves 403.gcc by ~80 instructions.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@61847 91177308-0d34-0410-b5e6-96231b3b80d8
2009-01-07 02:08:57 +00:00
autoconf
bindings
cmake
docs
examples
include The coalescer does not coalesce a virtual register to a physical register if any of the physical register's sub-register live intervals overlaps with the virtual register. This is overly conservative. It prevents a extract_subreg from being coalesced away: 2009-01-07 02:08:57 +00:00
lib The coalescer does not coalesce a virtual register to a physical register if any of the physical register's sub-register live intervals overlaps with the virtual register. This is overly conservative. It prevents a extract_subreg from being coalesced away: 2009-01-07 02:08:57 +00:00
projects
runtime
test The coalescer does not coalesce a virtual register to a physical register if any of the physical register's sub-register live intervals overlaps with the virtual register. This is overly conservative. It prevents a extract_subreg from being coalesced away: 2009-01-07 02:08:57 +00:00
tools make llvm-ld smart enough to link against native libraries that are 2009-01-05 19:01:32 +00:00
unittests
utils Improve support for type-generic vector intrinsics by teaching TableGen how 2009-01-07 00:09:01 +00:00
website
win32
Xcode
build-for-llvm-top.sh
CMakeLists.txt
configure
CREDITS.TXT
LICENSE.TXT
llvm.spec.in
Makefile
Makefile.common
Makefile.config.in
Makefile.rules
ModuleInfo.txt
README.txt Remove extra lines 2008-07-28 20:50:25 +00:00

README.txt 

Low Level Virtual Machine (LLVM)
================================

This directory and its subdirectories contain source code for the Low Level 
Virtual Machine, a toolkit for the construction of highly optimized compilers,
optimizers, and runtime environments. 

LLVM is open source software. You may freely distribute it under the terms of
the license agreement found in LICENSE.txt.

Please see the HTML documentation provided in docs/index.html for further
assistance with LLVM.