llvm-6502

mirror of https://github.com/c64scene-ar/llvm-6502.git synced 2024-12-14 11:32:34 +00:00

LLVM backend for 6502

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Arnold Schwaighofer f7af1987dd SimplifyCFG: If convert single conditional stores This transformation will transform a conditional store with a preceeding uncondtional store to the same location: a[i] = may-alias with a[i] load if (cond) a[i] = Y into an unconditional store. a[i] = X may-alias with a[i] load tmp = cond ? Y : X; a[i] = tmp We assume that on average the cost of a mispredicted branch is going to be higher than the cost of a second store to the same location, and that the secondary benefits of creating a bigger basic block for other optimizations to work on outway the potential case were the branch would be correctly predicted and the cost of the executing the second store would be noticably reflected in performance. hmmer's execution time improves by 30% on an imac12,2 on ref data sets. With this change we are on par with gcc's performance (gcc also performs this transformation). There was a 1.2 % performance improvement on a ARM swift chip. Other tests in the test-suite+external seem to be mostly uninfluenced in my experiments: This optimization was triggered on 41 tests such that the executable was different before/after the patch. Only 1 out of the 40 tests (dealII) was reproducable below 100% (by about .4%). Given that hmmer benefits so much I believe this to be a fair trade off. I am going to watch performance numbers across the builtbots and will revert this if anything unexpected comes up. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@179957 91177308-0d34-0410-b5e6-96231b3b80d8		2013-04-20 21:42:09 +00:00
autoconf	Refine fenv.h handling: check if the desired macros exist, before using	2013-03-25 13:13:33 +00:00
bindings	[python] Add markup option to disassembler	2012-12-01 21:57:30 +00:00
cmake	Don't explicitly provide -pie in MSan bootstrap of LLVM, as it's now implied by the driver	2013-04-12 07:18:55 +00:00
docs	Add CodeGen support for functions that always return arguments via a new parameter attribute 'returned', which is taken advantage of in target-independent tail call opportunity detection and in ARM call lowering (when placed on an integral first parameter).	2013-04-20 05:14:40 +00:00
examples	Update links to "Itanium C++ ABI: Exception Handling" document	2013-01-13 15:53:09 +00:00
include	Remove unused ShouldFoldAtomicFences flag.	2013-04-20 12:32:43 +00:00
lib	SimplifyCFG: If convert single conditional stores	2013-04-20 21:42:09 +00:00
projects	Print a warning message if compiler-rt can't be built because of old CMake version to make this requirement more visible to users	2013-03-05 14:43:07 +00:00
runtime	Remove GCDAProfiling.c. This copy is old, the copy in compiler-rt is newer and	2013-03-07 02:03:08 +00:00
test	SimplifyCFG: If convert single conditional stores	2013-04-20 21:42:09 +00:00
tools	Remove dead code.	2013-04-20 11:06:34 +00:00
unittests	Create a stub for DWARF parser unittests	2013-04-17 08:29:02 +00:00
utils	[asm parser] Add support for predicating MnemonicAlias based on the assembler	2013-04-18 22:35:36 +00:00
.arcconfig	Add .arcconfig to the repository. Useful if someone wants to use phabricator's command line tool.	2012-12-01 12:07:58 +00:00
.gitignore	Add extra vim swap file pattern	2012-10-09 23:48:34 +00:00
CMakeLists.txt	Enable all targets by default on Visual Studio.	2013-04-15 11:53:05 +00:00
CODE_OWNERS.TXT	Fix random typo.	2013-04-17 03:18:49 +00:00
configure	Refine fenv.h handling: check if the desired macros exist, before using	2013-03-25 13:13:33 +00:00
CREDITS.TXT	Add myself in the CREDITS.TXT	2013-04-11 13:15:39 +00:00
LICENSE.TXT	Add LICENSE.TXT covering contributions made by ARM.	2013-01-07 10:04:49 +00:00
llvm.spec.in
LLVMBuild.txt
Makefile	Improved svn repo searching for 'make update'	2013-01-28 03:19:57 +00:00
Makefile.common	Makefile.common: Update a description, s/Source/SOURCES/ , according to MakefileGuide.html#control-variables .	2012-12-07 01:43:23 +00:00
Makefile.config.in	Turn anonymous type in anonymous union warning back on after cleaning up	2013-03-15 00:43:00 +00:00
Makefile.rules	Make check depend on all.	2013-04-09 19:42:12 +00:00
README.txt	test	2013-04-17 05:34:03 +00:00

README.txt

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