Fork of llvm with experimental commits and workarounds for RPCS3
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Chris Lattner 1cdc77b8da enhance the compare/load/index optimization to work on *any* load
from a global with 32/64 elements or less (depending on whether
i64 is native on the target), generating a bitshift idiom to 
determine the result.  For example, on test4 we produce:

define i1 @test4(i32 %X) {
  %1 = lshr i32 933, %X                           ; <i32> [#uses=1]
  %2 = and i32 %1, 1                              ; <i32> [#uses=1]
  %R = icmp ne i32 %2, 0                          ; <i1> [#uses=1]
  ret i1 %R
}

This triggers in a number of interesting cases, for example, here's an
fp case:
@A.3255 = internal constant [4 x double] [double 4.100000e+00, double -3.900000e+00, double -1.000000e+00, double 1.000000e+00], align 32 ; <[4 x double]*> [#uses=7]
...
	   %7 = fcmp olt double %3, 0.000000e+00

In this case we make the slen2_tab global dead, which is nice:
@slen2_tab = internal constant [16 x i32] [i32 0, i32 1, i32 2, i32 3, i32 0, i32 1, i32 2, i32 3, i32 1, i32 2, i32 3, i32 1, i32 2, i32 3, i32 2, i32 3], align 32 ; <[16 x i32]*> [#uses=1]
...
	   %204 = icmp eq i32 %46, 0     

Perl has a bunch of these, also on the 'Perl_regkind' array:
@Perl_yygindex = internal constant [51 x i16] [i16 0, i16 0, i16 0, i16 0, i16 374, i16 351, i16 0, i16 -12, i16 0, i16 946, i16 413, i16 -83, i16 0, i16 0, i16 0, i16 -311, i16 -13, i16 4007, i16 2893, i16 0, i16 0, i16 0, i16 0, i16 0, i16 372, i16 -8, i16 0, i16 0, i16 246, i16 -131, i16 43, i16 86, i16 208, i16 -45, i16 -169, i16 987, i16 0, i16 0, i16 0, i16 0, i16 308, i16 0, i16 -271, i16 0, i16 0, i16 0, i16 0, i16 0, i16 0, i16 0, i16 0], align 32 ; <[51 x i16]*> [#uses=1]
...
  %1364 = icmp eq i16 %1361, 0

186.crafty really likes this on 64-bit machines, because it triggers on a bunch of globals like this:
@white_outpost = internal constant [64 x i8] c"\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\02\02\00\00\00\00\00\04\05\05\04\00\00\00\00\03\06\06\03\00\00\00\00\00\01\01\00\00\00\00\00\00\00\00\00\00\00", align 32 ; <[64 x i8]*> [#uses=2]

However the big winner is 403.gcc, which triggers hundreds of times, eliminating all the accesses to the 57-element arrays 'mode_class', mode_unit_size, mode_bitsize, regclass_map, etc.

go 64-bit machines :)

llvm-svn: 92415
2010-01-02 08:56:52 +00:00
autoconf Fix typos. Thanks to John Tytgat for noticing it! 2009-12-07 00:27:35 +00:00
bindings Fix another parallel make race condition. 2009-12-18 20:12:14 +00:00
cmake CMake: Update lib deps. 2009-12-19 21:27:30 +00:00
docs Regenerate. 2009-12-23 12:49:51 +00:00
examples fix PR5649 by making fib use the JIT instead of the interpreter, patch by Perry Lorier! 2009-12-01 01:56:27 +00:00
include teach instcombine to optimize pointer difference idioms involving constant 2010-01-01 22:29:12 +00:00
lib enhance the compare/load/index optimization to work on *any* load 2010-01-02 08:56:52 +00:00
projects Move DataTypes.h to include/llvm/System, update all users. This breaks the last 2009-10-26 01:35:46 +00:00
runtime OptimalEdgeProfiling: Creation of profiles. 2009-09-01 19:03:44 +00:00
test enhance the compare/load/index optimization to work on *any* load 2010-01-02 08:56:52 +00:00
tools Forward -O0 to llvm-gcc. 2010-01-02 08:27:23 +00:00
unittests Silence compiler warning. 2009-12-31 16:27:13 +00:00
utils Typo. 2010-01-01 04:40:54 +00:00
website
Xcode Remove the IA-64 backend. 2009-07-24 00:30:09 +00:00
build-for-llvm-top.sh Patch to build llvm with srcdir != objdir from 2009-01-23 08:42:38 +00:00
CMakeLists.txt Don't default warnings to ON on MSVC, the spew is enough to triple the build time. :/ 2009-12-01 19:11:36 +00:00
configure Fix typos. Thanks to John Tytgat for noticing it! 2009-12-07 00:27:35 +00:00
CREDITS.TXT Add myself to the blame list. 2009-08-20 15:20:15 +00:00
LICENSE.TXT Add regular expression matching support, based on OpenBSD regexec()/regcomp() 2009-08-30 08:24:09 +00:00
llvm.spec.in
Makefile Update install-clang target for clang-cc removal. 2009-12-12 21:17:54 +00:00
Makefile.common
Makefile.config.in Fix typos. Thanks to John Tytgat for noticing it! 2009-12-07 00:27:35 +00:00
Makefile.rules Add the rest of the build system logic for optional target disassemblers 2009-11-25 04:46:58 +00:00
ModuleInfo.txt Patch to build llvm with srcdir != objdir from 2009-01-23 08:42:38 +00:00
README.txt First test commit 2009-10-05 22:29:11 +00:00

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

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LLVM is open source software. You may freely distribute it under the terms of
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Please see the HTML documentation provided in docs/index.html for further
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