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LLVM backend for 6502
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Arnold Schwaighofer 08a0e8f8db LoopVectorizer: integer division is not a reduction operation 
Don't classify idiv/udiv as a reduction operation. Integer division is lossy.
For example : (1 / 2) * 4 != 4/2.

Example:

int a[] = { 2, 5, 2, 2}
int x = 80;

for()
  x /= a[i];

Scalar:
  x /= 2 // = 40
  x /= 5 // = 8
  x /= 2 // = 4
  x /= 2 // = 2

Vectorized:

 <80, 1> / <2,5> //= <40,0>
 <40, 0> / <2,2> //= <20,0>

 20*0 = 0

radar://13640654

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@179381 91177308-0d34-0410-b5e6-96231b3b80d8
2013-04-12 15:15:19 +00:00
autoconf Refine fenv.h handling: check if the desired macros exist, before using 2013-03-25 13:13:33 +00:00
bindings
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 Teach llvm-readobj to print ELF program headers 2013-04-12 04:07:39 +00:00
examples
include Revert broken pieces of r179373. 2013-04-12 12:13:51 +00:00
lib LoopVectorizer: integer division is not a reduction operation 2013-04-12 15:15:19 +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 LoopVectorizer: integer division is not a reduction operation 2013-04-12 15:15:19 +00:00
tools Revert broken pieces of r179373. 2013-04-12 12:13:51 +00:00
unittests Fix a disconcerting bug in Value::isUsedInBasicBlock, which gave wrong answers for blocks larger than 3 instrs. 2013-04-12 08:33:11 +00:00
utils Add CLAC/STAC instruction encoding/decoding support 2013-04-11 04:52:28 +00:00
.arcconfig
.gitignore
CMakeLists.txt Revert "TMP" 2013-04-10 12:08:57 +00:00
CODE_OWNERS.TXT Move info to CREDITS.TXT file. 2013-04-10 21:56:52 +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
llvm.spec.in
LLVMBuild.txt
Makefile Improved svn repo searching for 'make update' 2013-01-28 03:19:57 +00:00
Makefile.common
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 Revert "Test commit" 2013-02-22 19:19:41 +00:00

README.txt 

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