Owen Anderson
bbfa479f14
Clean up a bit.
...
llvm-svn: 29950
2006-08-29 06:10:56 +00:00
Nick Lewycky
9535a84c33
Add PredicateSimplifier pass. Collapses equal variables into one form
...
and simplifies expressions. This implements the optimization described
in PR807.
llvm-svn: 29947
2006-08-28 22:44:55 +00:00
Owen Anderson
ee603f511f
Make LoopUnroll fold excessive BasicBlocks. This results in a significant speedup of
...
gccas on 252.eon
llvm-svn: 29936
2006-08-28 02:09:46 +00:00
Chris Lattner
8a59e8be23
simplify AnalysisGroup registration, eliminating one typeid call.
...
llvm-svn: 29932
2006-08-28 00:42:29 +00:00
Chris Lattner
a39dcb5377
eliminate RegisterOpt. It does the same thing as RegisterPass.
...
llvm-svn: 29925
2006-08-27 22:42:52 +00:00
Chris Lattner
33bd5dcfb7
s|llvm/Support/Visibility.h|llvm/Support/Compiler.h|
...
llvm-svn: 29911
2006-08-27 12:54:02 +00:00
Owen Anderson
aac2dbf9dd
Fix a crash related to updating Phi nodes in the original header block. This was
...
causing a crash in 175.vpr
llvm-svn: 29887
2006-08-25 22:13:55 +00:00
Owen Anderson
e02cb4cda0
Add an assertion to check that we're really preserving LCSSA.
...
llvm-svn: 29886
2006-08-25 22:12:36 +00:00
Owen Anderson
b1d980f98a
Reapply the indvars patch, since nothing blew up last night.
...
llvm-svn: 29874
2006-08-25 17:41:25 +00:00
Owen Anderson
596b22375a
Revert my previous patch. Since there are some major changes that went in today,
...
I'm going to wait to put this in HEAD until tomorrow, so as not to clutter the nightly
tester.
llvm-svn: 29868
2006-08-25 03:45:57 +00:00
Owen Anderson
54c87a08ab
Specify that indvars actually preserve LCSSA. This has been done for a while, but I
...
forgot to put in the analysis usage.
llvm-svn: 29867
2006-08-25 03:32:13 +00:00
Owen Anderson
0aa48d0522
Implement unrolling of multiblock loops. This significantly improves the
...
utility of the LoopUnroll pass.
Also, add a testcase for multiblock-loop unrolling.
llvm-svn: 29859
2006-08-24 21:28:19 +00:00
Reid Spencer
1ae3d19c51
Fix a grammaro in a comment.
...
llvm-svn: 29765
2006-08-18 09:01:07 +00:00
Chris Lattner
d9ce68d3ec
Handle single-entry PHI nodes correctly. This fixes PR877 and
...
Transforms/CondProp/2006-08-14-SingleEntryPhiCrash.ll
llvm-svn: 29673
2006-08-14 21:38:05 +00:00
Chris Lattner
a75d3b6d0d
Don't attempt to split subloops out of a loop with a huge number of backedges.
...
Not only will this take huge amounts of compile time, the resultant loop nests
won't be useful for optimization. This reduces loopsimplify time on
Transforms/LoopSimplify/2006-08-11-LoopSimplifyLongTime.ll from ~32s to ~0.4s
with a debug build of llvm on a 2.7Ghz G5.
llvm-svn: 29647
2006-08-12 05:25:00 +00:00
Chris Lattner
0885025198
Reimplement the loopsimplify code which deletes edges from unreachable
...
blocks that target loop blocks.
Before, the code was run once per loop, and depended on the number of
predecessors each block in the loop had. Unfortunately, scanning preds can
be really slow when huge numbers of phis exist or when phis with huge numbers
of inputs exist.
Now, the code is run once per function and scans successors instead of preds,
which is far faster. In addition, the new code is simpler and is goto free,
woo.
This change speeds up a nasty testcase Duraid provided me from taking hours to
taking ~72s with a debug build. The functionality this implements is already
tested in the testsuite as Transforms/CodeExtractor/2004-03-13-LoopExtractorCrash.ll.
llvm-svn: 29644
2006-08-12 04:51:20 +00:00
Reid Spencer
dc0927cccf
Make this example pass use some things from lib/Support (EscapeString,
...
SlowOperatingInfo, Statistics). Besides providing an example of how to
use these facilities, it also serves to debug problems with runtime linking
when dlopening a loadable module. These three support facilities exercise
different combinations of Text/Weak Weak/Text and Text/Text linking
between the executable and the module.
llvm-svn: 29552
2006-08-07 23:17:24 +00:00
Reid Spencer
3f5e3c843a
For PR780:
...
1. Change the usage of LOADABLE_MODULE so that it implies all the things
necessary to make a loadable module. This reduces the user's burdern to
get a loadable module correctly built.
2. Document the usage of LOADABLE_MODULE in the MakefileGuide
3. Adjust the makefile for lib/Transforms/Hello to use the new specification
for building loadable modules
4. Adjust the sample project to not attempt to build a shared library for
its little library. This was just wasteful and not instructive at all.
llvm-svn: 29551
2006-08-07 23:12:15 +00:00
Chris Lattner
b7442c1f8b
Fix PR867 (and maybe 868) and testcsae:
...
Transforms/SimplifyCFG/2006-08-03-Crash.ll
llvm-svn: 29515
2006-08-03 21:40:24 +00:00
Chris Lattner
52419ac93e
Changes:
...
1. Update an obsolete comment.
2. Make the sorting by base an explicit (though still N^2) step, so
that the code is more clear on what it is doing.
3. Partition uses so that uses inside the loop are handled before uses
outside the loop.
Note that none of these changes currently changes the code inserted by LSR,
but they are a stepping stone to getting there.
This code is the result of some crazy pair programming with Nate. :)
llvm-svn: 29493
2006-08-03 06:34:50 +00:00
Chris Lattner
1768e89248
Add special check to avoid isLoop call. Simple, but doesn't seem to speed
...
up lcssa much in practice.
llvm-svn: 29465
2006-08-02 00:16:47 +00:00
Chris Lattner
a07bbb37e4
Replace the SSA update code in LCSSA with a bottom-up approach instead of a top
...
down approach, inspired by discussions with Tanya.
This approach is significantly faster, because it does not need dominator
frontiers and it does not insert extraneous unused PHI nodes. For example, on
252.eon, in a release-asserts build, this speeds up LCSSA (which is the slowest
pass in gccas) from 9.14s to 0.74s on my G5. This code is also slightly smaller
and significantly simpler than the old code.
Amusingly, in a normal Release build (which includes the
"assert(L->isLCSSAForm());" assertion), asserting that the result of LCSSA
is in LCSSA form is actually slower than the LCSSA transformation pass
itself on 252.eon. I will see if Loop::isLCSSAForm can be sped up next.
llvm-svn: 29463
2006-08-02 00:06:09 +00:00
Chris Lattner
92a0b69813
Add some advice
...
llvm-svn: 29324
2006-07-27 04:24:14 +00:00
Chris Lattner
3890fa2c4a
Minor comment tweaks
...
llvm-svn: 29226
2006-07-20 19:06:16 +00:00
Devang Patel
cb3c26fa6a
Make it fit into 80 cols.
...
llvm-svn: 29223
2006-07-20 18:03:39 +00:00
Devang Patel
07e0d34f7d
Add new constructor to accept vector of exported names while creating
...
InternalizePass.
llvm-svn: 29222
2006-07-20 17:48:05 +00:00
Owen Anderson
3d84b9e0cc
Add an assertion.
...
llvm-svn: 29199
2006-07-19 05:48:45 +00:00
Owen Anderson
7d68cbc39a
Make LoopUnroll not die on LCSSA Phis. This makes lencod work again.
...
llvm-svn: 29198
2006-07-19 05:45:14 +00:00
Owen Anderson
8a36136176
Fix a error that hadn't yet cause any problems, but I'm sure it would have
...
somewhere down the road.
llvm-svn: 29197
2006-07-19 03:51:48 +00:00
Chris Lattner
e1054a6cfe
silence warnings in a release build
...
llvm-svn: 29189
2006-07-18 21:48:57 +00:00
Evan Cheng
725fc9e73d
Only reuse a previous IV if it would not require a type conversion.
...
llvm-svn: 29186
2006-07-18 19:07:58 +00:00
Chris Lattner
3a664f7dc0
eliminate some ugly code, using ConstantExpr::getWithOperands instead.
...
llvm-svn: 29149
2006-07-14 22:21:31 +00:00
Owen Anderson
715e6d06e6
Hopefully the final attempt at making IndVars preserve LCSSA.
...
This should fix PR 831.
llvm-svn: 29141
2006-07-14 18:49:15 +00:00
Chris Lattner
f404323e66
Revert this patch temporarily until PR831 is fixed.
...
llvm-svn: 29134
2006-07-13 19:05:20 +00:00
Chris Lattner
b77e687f6f
Handle instructions in the map, but that map to a null pointer.
...
This unbreaks smg2000.
llvm-svn: 29127
2006-07-12 21:37:11 +00:00
Owen Anderson
d4000ea452
IndVars now (correctly) preserves LCSSA form.
...
llvm-svn: 29126
2006-07-12 21:29:14 +00:00
Chris Lattner
0d4c198ecd
In addition to deleting calls, the inliner can constant fold them as well.
...
Handle this case, which doesn't require a new callgraph edge. This fixes
a crash compiling MallocBench/gs.
llvm-svn: 29121
2006-07-12 18:37:18 +00:00
Chris Lattner
e5e2e8d917
Change the callgraph representation to store the callsite along with the
...
target CG node. This allows the inliner to properly update the callgraph
when using the pruning inliner. The pruning inliner may not copy over all
call sites from a callee to a caller, so the edges corresponding to those
call sites should not be copied over either.
This fixes PR827 and Transforms/Inline/2006-07-12-InlinePruneCGUpdate.ll
llvm-svn: 29120
2006-07-12 18:29:36 +00:00
Chris Lattner
8c650b87d6
Silence a warning produced in assertions-disabled mode
...
llvm-svn: 29108
2006-07-11 18:31:26 +00:00
Owen Anderson
0dd2844c05
Revert my indvars changes because they were breaking things. Unfortunately this
...
didn't start showing up until after the recent instcombine fixes.
llvm-svn: 29102
2006-07-11 07:25:33 +00:00
Owen Anderson
bc6e3cc1b3
Add a comment, and fix a typo that broke the build.
...
llvm-svn: 29094
2006-07-10 22:15:25 +00:00
Owen Anderson
ea91b4ae30
Don't indent the entire function.
...
llvm-svn: 29093
2006-07-10 22:03:18 +00:00
Chris Lattner
8c5c35af13
Recognize 16-bit bswaps by relaxing overconstrained pattern.
...
This implements Transforms/InstCombine/bswap.ll:test[34].
llvm-svn: 29087
2006-07-10 20:25:24 +00:00
Owen Anderson
81986ede26
Make instcombine not remove Phi nodes when LCSSA is live.
...
llvm-svn: 29083
2006-07-10 19:03:49 +00:00
Owen Anderson
7c03596d93
Fix typo in the comment.
...
llvm-svn: 29078
2006-07-09 21:35:40 +00:00
Owen Anderson
5812f5d7a8
Add a fix for an issue where LCSSA would fail to insert undef's in some corner
...
cases. Ideally, this issue will go away in the future as LCSSA gets smarter
about which Phi nodes it inserts.
llvm-svn: 29076
2006-07-09 08:14:06 +00:00
Chris Lattner
ad4fa73f50
Fix PR820 and Transforms/GlobalOpt/2006-07-07-InlineAsmCrash.ll
...
llvm-svn: 29071
2006-07-07 21:37:01 +00:00
Chris Lattner
496bd3fbf6
Use hidden visibility to make symbols in an anonymous namespace get
...
dropped. This shrinks libllvmgcc.dylib another 67K
llvm-svn: 28975
2006-06-28 23:17:24 +00:00
Chris Lattner
3aac973374
Shrink libllvmgcc.dylib by another 23K
...
llvm-svn: 28972
2006-06-28 22:08:15 +00:00
Owen Anderson
8f95262124
Switch to a very conservative heuristic for determining when loop-unswitching
...
will be profitable. This is mainly to remove some cases where excessive
unswitching would result in long compile times and/or huge generated code.
Once someone comes up with a better heuristic that avoids these cases, this
should be switched out.
llvm-svn: 28962
2006-06-28 17:47:50 +00:00
Chris Lattner
d6dbd6d552
Fix Transforms/InstCombine/2006-06-28-infloop.ll
...
llvm-svn: 28961
2006-06-28 17:34:50 +00:00
Chris Lattner
1d8a141786
Don't unswitch really large loops even if they are mostly filled with empty
...
blocks.
llvm-svn: 28959
2006-06-28 16:38:55 +00:00
Andrew Lenharth
764ee8eb29
Catch more function pointer casting problems
...
Remove the Function pointer cast in these calls, converting it to
a cast of argument.
%tmp60 = tail call int cast (int (ulong)* %str to int (int)*)( int 10 )
%tmp60 = tail call int cast (int (ulong)* %str to int (int)*)( uint %tmp51 )
llvm-svn: 28953
2006-06-28 01:01:52 +00:00
Owen Anderson
f9dbb7c834
Fix for 2006-06-27-DeadSwitchCase.ll
...
Be more careful when updating Phi nodes after eliminating dead switch cases. Fix
proposed by Chris.
llvm-svn: 28947
2006-06-27 22:26:09 +00:00
Chris Lattner
92703315b1
Fix Transforms/DeadArgElim/2006-06-27-struct-ret.ll. -deadargelim should not
...
remove the struct return argument of a csret function, even if it is obviously
dead.
llvm-svn: 28943
2006-06-27 21:05:04 +00:00
Owen Anderson
1c3b04d485
De-pessimize the handling of LCSSA Phi nodes in IndVarSimplify. Hopefully this
...
will make Shootout-C/nestedloop faster.
llvm-svn: 28924
2006-06-27 02:17:08 +00:00
Chris Lattner
b12f94b14a
random code cleanups, no functionality change
...
llvm-svn: 28914
2006-06-26 19:10:05 +00:00
Owen Anderson
71056f7113
Make LoopUnswitch able to unswitch loops with live-out values by taking advantage
...
of LCSSA. This results several times the number of unswitchings occurring on
tests such and timberwolfmc, unix-tbl, and ldecod.
llvm-svn: 28912
2006-06-26 07:44:36 +00:00
Chris Lattner
25b04b4249
Fix IndVarsSimplify/2006-06-16-Indvar-LCSSA-Crash.ll, a case where a
...
"LCSSA" phi node causes indvars to break dominance properties. This fixes
causes indvars to avoid inserting aggressive code in this case, instead
indvars should be fixed to be more aggressive in the face of lcssa phi's.
llvm-svn: 28850
2006-06-17 01:02:31 +00:00
Evan Cheng
884b3a29da
Add missing casts. This fixed some regressions.
...
llvm-svn: 28834
2006-06-16 18:37:15 +00:00
Evan Cheng
763d7462d5
More libcall transformations:
...
printf("%s\n", str) -> puts(str)
printf("%c", c) -> putchar(c)
Also fixed fprintf(file, "%c", c) -> fputc(c, file)
llvm-svn: 28815
2006-06-16 08:36:35 +00:00
Evan Cheng
bde00a97a7
Simplify fprintf(file, "%s", str) to fputs(str, file).
...
llvm-svn: 28814
2006-06-16 04:52:30 +00:00
Chris Lattner
d99c49c826
Implement Transforms/InstCombine/bswap.ll, turning common shift/and/or bswap
...
idioms into bswap intrinsics.
llvm-svn: 28803
2006-06-15 19:07:26 +00:00
Chris Lattner
68a0b5c8a0
Fix Transforms/LoopUnswitch/2006-06-13-SingleEntryPHI.ll, a loop unswitch
...
bug exposed by the recent lcssa work.
llvm-svn: 28779
2006-06-14 04:46:17 +00:00
Chris Lattner
1b42069db1
Use the PotDoms map to memoize 'dominating value' lookup. With this patch,
...
LCSSA is still the slowest pass when gccas'ing 252.eon, but now it only takes
39s instead of 289s. :)
llvm-svn: 28776
2006-06-14 01:13:57 +00:00
Owen Anderson
c50df7da72
Fix another instance where PHI nodes need special treatment.
...
llvm-svn: 28774
2006-06-13 20:50:09 +00:00
Owen Anderson
f43ab30bc0
Fix a bug that was causing major slowdowns in povray. This was due to LCSSA
...
not handling PHI nodes correctly when determining if a value was live-out.
This patch reduces the number of detected live-out variables in the testcase
from 6565 to 485.
llvm-svn: 28771
2006-06-13 19:37:18 +00:00
Owen Anderson
276e728e4b
Reapply my 6/9 changes. The bug Evan saw no longer occurs.
...
llvm-svn: 28759
2006-06-12 21:49:21 +00:00
Chris Lattner
649af38df3
Fix an infinite loop on Transforms/SimplifyCFG/2006-06-12-InfLoop.ll
...
llvm-svn: 28758
2006-06-12 20:18:01 +00:00
Owen Anderson
a947d699dd
Fix for 2006-06-26-MultipleExitsSingleBlock.
...
If a single exit block has multiple predecessors within the loop, it will
appear in the exit blocks list more than once. LCSSA needs to take that into
account so that it doesn't double process that exit block.
llvm-svn: 28750
2006-06-12 07:10:16 +00:00
Owen Anderson
15b85dbfa5
Re-commit the safe parts of my 6/9 patch. Still working on fixing the unsafe parts.
...
llvm-svn: 28748
2006-06-11 19:22:28 +00:00
Evan Cheng
d99c8e2e5f
Back out Owen's 6/9 changes. They broke MultiSource/Benchmarks/Prolangs-C/bison (and perhaps others).
...
llvm-svn: 28747
2006-06-11 09:32:57 +00:00
Owen Anderson
4a0ceb1e6d
Add LCSSA as a requirement for LoopUnswitch, and assert that LoopUnswitch preserves
...
LCSSA.
llvm-svn: 28739
2006-06-09 18:40:32 +00:00
Owen Anderson
6c2f7512a6
Make Loop able to verify that it is in LCSSA-form, and have the LCSSA pass assert
...
on this.
llvm-svn: 28738
2006-06-09 18:33:30 +00:00
Evan Cheng
6039769dc1
RewriteExpr, either the new PHI node of induction variable or the
...
post-increment value, should be first cast to the appropriated type (to the
type of the common expr). Otherwise, the rewrite of a use based on (common +
iv) may end up with an incorrect type.
llvm-svn: 28735
2006-06-09 00:12:42 +00:00
Owen Anderson
0d9583aa41
Update some comments, and expose LCSSAID in preparation for having other passes
...
require LCSSA.
llvm-svn: 28734
2006-06-08 20:02:53 +00:00
Reid Spencer
59137abcac
Fix a spello in a comment.
...
llvm-svn: 28714
2006-06-07 21:24:10 +00:00
Chris Lattner
19394c3f30
Fix a bug in a recent patch. This fixes UnitTests/Vector/Altivec/casts.c on
...
PPC/altivec
llvm-svn: 28698
2006-06-06 22:26:02 +00:00
Owen Anderson
04f6f0775a
Fix some formatting, and use inLoop() when appropriate.
...
llvm-svn: 28694
2006-06-06 04:36:36 +00:00
Owen Anderson
dc8495f4ad
Stop a memory leak, and update some comments.
...
llvm-svn: 28693
2006-06-06 04:28:30 +00:00
Owen Anderson
4343713be4
Some more clean-up, and squash an IDF-Phi related bug.
...
llvm-svn: 28680
2006-06-04 00:55:19 +00:00
Owen Anderson
1a72d98dd2
Various clean-ups suggested by Chris.
...
llvm-svn: 28678
2006-06-04 00:02:23 +00:00
Owen Anderson
b83c3beb44
Fix a bug in Phi-noded insertion. Also, update some comments to reflect what's
...
actually going on.
llvm-svn: 28677
2006-06-03 23:22:50 +00:00
Chris Lattner
6cca762d5f
Remove unneeded hook. Patch by Anton K. Thanks!
...
llvm-svn: 28664
2006-06-02 19:11:46 +00:00
Chris Lattner
0f5ef733cc
Force anything that #includes llvm/Transforms/Utils/UnifyFunctionExitNodes.h
...
to link in the implementation. Thanks to Anton Korobeynikov for figuring out
what was going on here.
llvm-svn: 28660
2006-06-02 18:40:06 +00:00
Chris Lattner
3300df2fb9
Remove dead #include
...
llvm-svn: 28642
2006-06-01 20:02:28 +00:00
Chris Lattner
93c46b83b6
Make the "pruning cloner" smarter. As it propagates constants through the
...
code (while cloning) it often gets the branch/switch instructions. Since it
knows that edges of the CFG are dead, it need not clone (or even look) at
the obviously dead blocks. This should speed up the inliner substantially on
code where there are lots of inlinable calls to functions with constant
arguments. On C++ code in particular, this kicks in.
llvm-svn: 28641
2006-06-01 19:19:23 +00:00
Chris Lattner
339d8b5ba9
Silence a -pedantic warning.
...
llvm-svn: 28632
2006-06-01 17:16:21 +00:00
Owen Anderson
1b0cd45469
Remove a FIXME that was fixed with my last patch.
...
llvm-svn: 28619
2006-06-01 06:07:40 +00:00
Owen Anderson
facd63d07c
More cleanups. Also, add a special case for updating PHI nodes, and
...
reimplement getValueDominatingFunction to walk the DominanceTree rather than
just searching blindly.
llvm-svn: 28618
2006-06-01 06:05:47 +00:00
Chris Lattner
36f99c7c1d
Swap the order of operands created here. For +&|^, the order doesn't matter,
...
but for sub, it really does! Fix fixes a miscompilation of fibheap_cut in
llvmgcc4.
llvm-svn: 28600
2006-05-31 21:14:00 +00:00
Owen Anderson
aae280d83c
Extract a huge loop into a helper method. Fix a few iterator-invalidation bugs.
...
llvm-svn: 28599
2006-05-31 20:55:06 +00:00
Owen Anderson
d46a77c3c8
Add Use replacement. Assuming there is nothing horribly wrong with this, LCSSA
...
is now theoretically feature-complete. It has not, however, been thoroughly
test, and is still considered experimental.
llvm-svn: 28529
2006-05-29 01:00:00 +00:00
Owen Anderson
a857559867
Major think-o. Iterate over all live out-of-loop values, and perform the
...
other calculations on each individually, rather than trying to delay it and do
them all at the end.
llvm-svn: 28527
2006-05-28 19:33:28 +00:00
Owen Anderson
703f6baab0
Make LCSSA insert proper Phi nodes throughout the rest of the CFG by computing
...
the iterated Dominance Frontier of the loop-closure Phi's. This is the
second phase of the LCSSA pass. The third phase (coming soon) will be to
update all uses of loop variables to use the loop-closure Phi's instead.
llvm-svn: 28524
2006-05-27 18:47:11 +00:00
Chris Lattner
0189e09b89
Fix some regression from the inliner patch I committed last night. This fixes
...
ldecod, lencod, and SPASS.
llvm-svn: 28523
2006-05-27 17:28:13 +00:00
Chris Lattner
04d52ee9a2
Switch the inliner over to using CloneAndPruneFunctionInto. This effectively
...
makes it so that it constant folds instructions on the fly. This is good
for several reasons:
0. Many instructions are constant foldable after inlining, particularly if
inlining a call with constant arguments.
1. Without this, the inliner has to allocate memory for all of the instructions
that can be constant folded, then a subsequent pass has to delete them. This
gets the job done without this extra work.
2. This makes the inliner *pass* a bit more aggressive: in particular, it
partially solves a phase order issue where the inliner would inline lots
of code that folds away to nothing, but think that the resultant function
is big because of this code that will be gone. Now the code never exists.
This is the first part of a 2-step process. The second part will be smart
enough to see when this implicit constant folding propagates a constant into
a branch or switch instruction, making CFG edges dead.
This implements Transforms/Inline/inline_constprop.ll
llvm-svn: 28521
2006-05-27 01:28:04 +00:00
Chris Lattner
12c9d54f79
Implement a new method, CloneAndPruneFunctionInto, as documented.
...
llvm-svn: 28519
2006-05-27 01:22:24 +00:00
Chris Lattner
1835cfb302
Refactor some code to expose an interface to constant fold and instruction given it's opcode, typeand operands.
...
llvm-svn: 28517
2006-05-27 01:18:04 +00:00
Owen Anderson
1843c1ee17
A few small clean-ups, and the addition of an LCSSA statistic.
...
llvm-svn: 28512
2006-05-27 00:31:37 +00:00
Owen Anderson
d706fc78b2
Fix a copy-and-paste-o that would break some compilers.
...
llvm-svn: 28507
2006-05-26 21:19:17 +00:00
Owen Anderson
2414055ac6
Clean up and refactor LCSSA a bunch. It should also run faster now, though
...
there's still a lot of work to be done on it.
llvm-svn: 28506
2006-05-26 21:11:53 +00:00
Chris Lattner
0043931185
Implement Transforms/InstCombine/store.ll:test2.
...
llvm-svn: 28503
2006-05-26 19:19:20 +00:00
Owen Anderson
93098cfc4c
Skeletal LCSSA pass. This is currently non-functional. Expect functionality
...
and documentation updates soo.
llvm-svn: 28495
2006-05-26 13:58:26 +00:00
Chris Lattner
c6c2770e08
Transform things like (splat(splat)) -> splat
...
llvm-svn: 28490
2006-05-26 00:29:06 +00:00
Chris Lattner
261299e3f5
Introduce a helper function that simplifies interpretation of shuffle masks.
...
No functionality change.
llvm-svn: 28489
2006-05-25 23:48:38 +00:00
Chris Lattner
c678c720a7
Turn (cast (shuffle (cast)) -> shuffle (cast) if it reduces the # casts in
...
the program. This exposes more opportunities for the instcombiner, and implements
vec_shuffle.ll:test6
llvm-svn: 28487
2006-05-25 23:24:33 +00:00
Chris Lattner
5df88a112b
extract element from a shuffle vector can be trivially turned into an
...
extractelement from the SV's source. This implement vec_shuffle.ll:test[45]
llvm-svn: 28485
2006-05-25 22:53:38 +00:00
Chris Lattner
d3eff919d8
Revert a patch that is unsafe, due to out of range array accesses in inner
...
array scopes possibly accessing valid memory in outer subscripts.
llvm-svn: 28478
2006-05-25 21:25:12 +00:00
Chris Lattner
0b38bc2a99
Patch for a new instcombine xform, patch contributed by Nick Lewycky!
...
This implements Transforms/InstCombine/2006-05-10-InvalidIndexUndef.ll
llvm-svn: 28450
2006-05-24 17:34:30 +00:00
Chris Lattner
f604017e47
Patches to make the LLVM sources more -pedantic clean. Patch provided
...
by Anton Korobeynikov! This is a step towards closing PR786.
llvm-svn: 28447
2006-05-24 17:04:05 +00:00
Chris Lattner
1ddd46999b
Silence a bogus gcc warning
...
llvm-svn: 28422
2006-05-20 23:14:03 +00:00
Reid Spencer
8d035f492c
Fix a doxygen problem and break lines at 80 columns
...
llvm-svn: 28395
2006-05-19 19:09:46 +00:00
Chris Lattner
cc9a99f371
Declare that lowerinvoke doesn't interact with other lowering passes.
...
Patch written by Domagoj Babic!
llvm-svn: 28367
2006-05-17 21:05:27 +00:00
Chris Lattner
9a0d02f8f7
Add a CloneModule call that exposes the mapping of values from the old module
...
to the new module. Patch provided by Nick Lewycky!
llvm-svn: 28349
2006-05-17 18:05:35 +00:00
Chris Lattner
5aa7f78065
remove some dead code identified by coverity
...
llvm-svn: 28289
2006-05-14 18:45:44 +00:00
Chris Lattner
4ad747c469
remove dead variables
...
llvm-svn: 28286
2006-05-14 18:33:57 +00:00
Evan Cheng
111642322d
Backing out last check-in for now. It's causing an infinite loop gccas lencode.
...
llvm-svn: 28284
2006-05-14 06:46:03 +00:00
Chris Lattner
c927dced9e
Add/Sub/Mul are safe to promote here as well. Incrementing a single-bit
...
bitfield now gives this code:
_plus:
lwz r2, 0(r3)
rlwimi r2, r2, 0, 1, 31
xoris r2, r2, 32768
stw r2, 0(r3)
blr
instead of this:
_plus:
lwz r2, 0(r3)
srwi r4, r2, 31
slwi r4, r4, 31
addis r4, r4, -32768
rlwimi r2, r4, 0, 0, 0
stw r2, 0(r3)
blr
this can obviously still be improved.
llvm-svn: 28275
2006-05-13 02:16:08 +00:00
Chris Lattner
eea864472d
Implement simple promotion for cast elimination in instcombine. This is
...
currently very limited, but can be extended in the future. For example,
we now compile:
uint %test30(uint %c1) {
%c2 = cast uint %c1 to ubyte
%c3 = xor ubyte %c2, 1
%c4 = cast ubyte %c3 to uint
ret uint %c4
}
to:
_xor:
movzbl 4(%esp), %eax
xorl $1, %eax
ret
instead of:
_xor:
movb $1, %al
xorb 4(%esp), %al
movzbl %al, %eax
ret
More impressively, we now compile:
struct B { unsigned bit : 1; };
void xor(struct B *b) { b->bit = b->bit ^ 1; }
To (X86/PPC):
_xor:
movl 4(%esp), %eax
xorl $-2147483648, (%eax)
ret
_xor:
lwz r2, 0(r3)
xoris r2, r2, 32768
stw r2, 0(r3)
blr
instead of (X86/PPC):
_xor:
movl 4(%esp), %eax
movl (%eax), %ecx
movl %ecx, %edx
shrl $31, %edx
# TRUNCATE movb %dl, %dl
xorb $1, %dl
movzbl %dl, %edx
andl $2147483647, %ecx
shll $31, %edx
orl %ecx, %edx
movl %edx, (%eax)
ret
_xor:
lwz r2, 0(r3)
srwi r4, r2, 31
xori r4, r4, 1
rlwimi r2, r4, 31, 0, 0
stw r2, 0(r3)
blr
This implements InstCombine/cast.ll:test30.
llvm-svn: 28273
2006-05-13 02:06:03 +00:00
Chris Lattner
4bbc1d8e95
Remove some dead variables.
...
Fix a nasty bug in the memcmp optimizer where we used the wrong variable!
llvm-svn: 28269
2006-05-12 23:35:26 +00:00
Chris Lattner
08efc01479
Remove dead stuff
...
llvm-svn: 28268
2006-05-12 23:32:01 +00:00
Chris Lattner
3fad520c62
Refactor some code, making it simpler.
...
When doing the initial pass of constant folding, if we get a constantexpr,
simplify the constant expr like we would do if the constant is folded in the
normal loop.
This fixes the missed-optimization regression in
Transforms/InstCombine/getelementptr.ll last night.
llvm-svn: 28224
2006-05-11 17:11:52 +00:00
Chris Lattner
e8fe3f2a08
Two changes:
...
1. Implement InstCombine/deadcode.ll by not adding instructions in unreachable
blocks (due to constants in conditional branches/switches) to the worklist.
This causes them to be deleted before instcombine starts up, leading to
better optimization.
2. In the prepass over instructions, do trivial constprop/dce as we go. This
has the effect of improving the effectiveness of #1 . In addition, it
*significantly* speeds up instcombine on test cases with large amounts of
constant folding code (for example, that produced by code specialization
or partial evaluation). In one example, it speeds up instcombine from
0.0589s to 0.0224s with a release build (a 2.6x speedup).
llvm-svn: 28215
2006-05-10 19:00:36 +00:00
Chris Lattner
f49a22d601
Patch to make some xforms preserve each other. Patch contributed by
...
Domagoj Babic!
llvm-svn: 28181
2006-05-09 04:13:41 +00:00
Chris Lattner
7661770087
Move some code around.
...
Make the "fold (and (cast A), (cast B)) -> (cast (and A, B))" transformation
only apply when both casts really will cause code to be generated. If one or
both doesn't, then this xform doesn't remove a cast.
This fixes Transforms/InstCombine/2006-05-06-Infloop.ll
llvm-svn: 28141
2006-05-06 09:00:16 +00:00
Chris Lattner
73bfc4c2ea
Fix an infinite loop compiling oggenc last night.
...
llvm-svn: 28128
2006-05-05 20:51:30 +00:00
Chris Lattner
95637c4889
Implement InstCombine/cast.ll:test29
...
llvm-svn: 28126
2006-05-05 06:39:07 +00:00
Chris Lattner
55938f67ae
Fix Transforms/InstCombine/2006-05-04-DemandedBitCrash.ll
...
llvm-svn: 28101
2006-05-04 17:33:35 +00:00
Chris Lattner
1275941193
Add pass ID's for various passes, so they can be AddRequiredID. Patch by
...
Domagoj Babic!
llvm-svn: 28048
2006-05-02 04:24:36 +00:00
Chris Lattner
4c79d3b238
Fix InstCombine/2006-04-28-ShiftShiftLongLong.ll
...
llvm-svn: 28019
2006-04-28 22:21:41 +00:00
Chris Lattner
2118062b9c
Fix Transforms/Reassociate/2006-04-27-ReassociateVector.ll
...
llvm-svn: 28007
2006-04-28 04:14:49 +00:00
Chris Lattner
3f6a151e2d
Add support for inserting undef into a vector. This implements
...
Transforms/InstCombine/vec_insert_to_shuffle.ll
llvm-svn: 27997
2006-04-27 21:14:21 +00:00
Chris Lattner
be67e21327
Fix some nondeterminstic behavior in the mem2reg pass that (in addition to
...
nondeterminism being bad) could cause some trivial missed optimizations (dead
phi nodes being left around for later passes to clean up).
With this, llvm-gcc4 now bootstraps and correctly compares. I don't know
why I never tried to do it before... :)
llvm-svn: 27984
2006-04-27 01:14:43 +00:00
Chris Lattner
01afcd337a
Fix Transforms/ScalarRepl/2006-04-20-PromoteCrash.ll
...
llvm-svn: 27912
2006-04-20 20:48:50 +00:00
Andrew Lenharth
e2b150550a
Make code match cvs commit message :)
...
llvm-svn: 27881
2006-04-20 15:41:37 +00:00
Andrew Lenharth
8f08647a6d
If we can convert the return pointer type into an integer that IntPtrType
...
can be converted to losslessly, we can continue the conversion to a direct call.
llvm-svn: 27880
2006-04-20 14:56:47 +00:00
Chris Lattner
76beeb373d
Turn x86 unaligned load/store intrinsics into aligned load/store instructions
...
if the pointer is known aligned.
llvm-svn: 27781
2006-04-17 22:26:56 +00:00
Chris Lattner
4422d3de1b
Fix a bug in the 'shuffle(undef,x,mask) -> shuffle(x, undef,mask')' xform
...
Make the insert/extract elt -> shuffle code more aggressive.
This fixes CodeGen/PowerPC/vec_shuffle.ll
llvm-svn: 27728
2006-04-16 00:51:47 +00:00
Chris Lattner
da260db137
Canonicalize shuffle(undef,x,mask) -> shuffle(x, undef,mask').
...
llvm-svn: 27727
2006-04-16 00:03:56 +00:00
Chris Lattner
055889cfb9
significant cleanups to code that uses insert/extractelt heavily. This builds
...
maximal shuffles out of them where possible.
llvm-svn: 27717
2006-04-15 01:39:45 +00:00
Chris Lattner
b3cae60d0b
Teach scalarrepl to promote unions of vectors and floats, producing
...
insert/extractelement operations. This implements
Transforms/ScalarRepl/vector_promote.ll
llvm-svn: 27710
2006-04-14 21:42:41 +00:00
Andrew Lenharth
bffed48656
linear -> constant time
...
llvm-svn: 27652
2006-04-13 13:43:31 +00:00
Reid Spencer
56aa7c79b7
Get rid of a signed/unsigned compare warning.
...
llvm-svn: 27625
2006-04-12 19:28:15 +00:00
Chris Lattner
7900e6da3b
Turn casts into getelementptr's when possible. This enables SROA to be more
...
aggressive in some cases where LLVMGCC 4 is inserting casts for no reason.
This implements InstCombine/cast.ll:test27/28.
llvm-svn: 27620
2006-04-12 18:09:35 +00:00
Chris Lattner
ec4fbd3b41
Implement vec_shuffle.ll:test3
...
llvm-svn: 27573
2006-04-10 23:06:36 +00:00
Chris Lattner
42be18f65f
Implement InstCombine/vec_shuffle.ll:test[12]
...
llvm-svn: 27571
2006-04-10 22:45:52 +00:00
Andrew Lenharth
b3f434b83d
Add a simple pass to make sure that all (non-library) calls to malloc and free
...
are visible to analysis as intrinsics. That is, make sure someone doesn't pass
free around by address in some struct (as happens in say 176.gcc).
This doesn't get rid of any indirect calls, just ensure calls to free and malloc
are always direct.
llvm-svn: 27560
2006-04-10 19:26:09 +00:00
Chris Lattner
a0a718c0cc
Add supprot for shufflevector
...
llvm-svn: 27513
2006-04-08 01:19:12 +00:00
Chris Lattner
32b65613d9
Fix inlining of insert/extract element constantexprs
...
llvm-svn: 27478
2006-04-07 04:41:03 +00:00
Chris Lattner
bc0489232b
Lower vperm(x,y, mask) -> shuffle(x,y,mask) if mask is constant. This allows
...
us to compile oh-so-realistic stuff like this:
vec_vperm(A, B, (vector unsigned char){14});
to:
vspltb v0, v0, 14
instead of:
vspltisb v0, 14
vperm v0, v2, v1, v0
llvm-svn: 27452
2006-04-06 19:19:17 +00:00
Chris Lattner
42a1e621f1
vector casts of casts are eliminable. Transform this:
...
%tmp = cast <4 x uint> %tmp to <4 x int> ; <<4 x int>> [#uses=1]
%tmp = cast <4 x int> %tmp to <4 x float> ; <<4 x float>> [#uses=1]
into:
%tmp = cast <4 x uint> %tmp to <4 x float> ; <<4 x float>> [#uses=1]
llvm-svn: 27355
2006-04-02 05:43:13 +00:00
Chris Lattner
3c994295fe
Allow transforming this:
...
%tmp = cast <4 x uint>* %testData to <4 x int>* ; <<4 x int>*> [#uses=1]
%tmp = load <4 x int>* %tmp ; <<4 x int>> [#uses=1]
to this:
%tmp = load <4 x uint>* %testData ; <<4 x uint>> [#uses=1]
%tmp = cast <4 x uint> %tmp to <4 x int> ; <<4 x int>> [#uses=1]
llvm-svn: 27353
2006-04-02 05:37:12 +00:00
Chris Lattner
cb26b2dfe8
Turn altivec lvx/stvx intrinsics into loads and stores. This allows the
...
elimination of one load from this:
int AreSecondAndThirdElementsBothNegative( vector float *in ) {
#define QNaN 0x7FC00000
const vector unsigned int testData = (vector unsigned int)( QNaN, 0, 0, QNaN );
vector float test = vec_ld( 0, (float*) &testData );
return ! vec_any_ge( test, *in );
}
Now generating:
_AreSecondAndThirdElementsBothNegative:
mfspr r2, 256
oris r4, r2, 49152
mtspr 256, r4
li r4, lo16(LCPI1_0)
lis r5, ha16(LCPI1_0)
addi r6, r1, -16
lvx v0, r5, r4
stvx v0, 0, r6
lvx v1, 0, r3
vcmpgefp. v0, v0, v1
mfcr r3, 2
rlwinm r3, r3, 27, 31, 31
xori r3, r3, 1
cntlzw r3, r3
srwi r3, r3, 5
mtspr 256, r2
blr
llvm-svn: 27352
2006-04-02 05:30:25 +00:00
Chris Lattner
e314cf19ba
Adjust to change in Intrinsics.gen interface.
...
llvm-svn: 27344
2006-04-02 03:35:01 +00:00
Chris Lattner
704770bfe7
add valuemapper support for inline asm
...
llvm-svn: 27332
2006-04-01 23:17:11 +00:00
Chris Lattner
c2e9b030da
Fix InstCombine/2006-04-01-InfLoop.ll
...
llvm-svn: 27330
2006-04-01 22:05:01 +00:00
Chris Lattner
497bbd4650
Fold A^(B&A) -> (B&A)^A
...
Fold (B&A)^A == ~B & A
This implements InstCombine/xor.ll:test2[56]
llvm-svn: 27328
2006-04-01 08:03:55 +00:00
Chris Lattner
79819f52dc
If we can look through vector operations to find the scalar version of an
...
extract_element'd value, do so.
llvm-svn: 27323
2006-03-31 23:01:56 +00:00
Chris Lattner
0af2e8be73
extractelement(undef,x) -> undef
...
llvm-svn: 27300
2006-03-31 18:25:14 +00:00
Chris Lattner
e57e873543
Fix Transforms/InstCombine/2006-03-30-ExtractElement.ll
...
llvm-svn: 27261
2006-03-30 22:02:40 +00:00
Chris Lattner
dc5d97a341
teach the inliner to work with packed constants
...
llvm-svn: 27161
2006-03-27 05:50:18 +00:00
Chris Lattner
bc48efc7fa
Don't crash on packed logical ops
...
llvm-svn: 27125
2006-03-25 21:58:26 +00:00
Chris Lattner
826dbd7173
Fix spello
...
llvm-svn: 27052
2006-03-24 07:14:34 +00:00
Chris Lattner
37951daad5
add the actual cost to the debug info
...
llvm-svn: 27051
2006-03-24 07:14:00 +00:00
Jim Laskey
88493ace30
Strip changes to llvm.dbg intrinsics.
...
llvm-svn: 26993
2006-03-23 18:11:33 +00:00
Jim Laskey
5df6eab07d
Can't combine anymore - we don't have a chain through llvm.dbg intrinsics.
...
llvm-svn: 26992
2006-03-23 18:10:42 +00:00
Chris Lattner
a779db7473
silence a bogus gcc warning
...
llvm-svn: 26953
2006-03-22 17:27:24 +00:00
Chris Lattner
986357c54c
Teach cee to propagate through switch statements. This implements
...
Transforms/CorrelatedExprs/switch.ll
Patch contributed by Eric Kidd!
llvm-svn: 26872
2006-03-19 19:37:24 +00:00
Evan Cheng
7955a187b1
- Fixed a bogus if condition.
...
- Added more debugging info.
- Allow reuse of IV of negative stride. e.g. -4 stride == 2 * iv of -2 stride.
llvm-svn: 26841
2006-03-18 08:03:12 +00:00
Evan Cheng
afe1ee3496
Sort StrideOrder so we can process the smallest strides first. This allows
...
for more IV reuses.
llvm-svn: 26837
2006-03-18 00:44:49 +00:00
Evan Cheng
fa1b885135
Allow users of iv / stride to be rewritten with expression that is a multiply
...
of a smaller stride even if they have a common loop invariant expression part.
llvm-svn: 26828
2006-03-17 19:52:23 +00:00
Evan Cheng
db35180b27
For each loop, keep track of all the IV expressions inserted indexed by
...
stride. For a set of uses of the IV of a stride which is a multiple
of another stride, do not insert a new IV expression. Rather, reuse the
previous IV and rewrite the uses as uses of IV expression multiplied by
the factor.
e.g.
x = 0 ...; x ++
y = 0 ...; y += 4
then use of y can be rewritten as use of 4*x for x86.
llvm-svn: 26803
2006-03-16 21:53:05 +00:00
Chris Lattner
b26656cc15
Teach the strip pass to strip type names in addition to value names. This
...
is fallout from the type/value split in the symtab long long ago :)
llvm-svn: 26785
2006-03-15 19:22:41 +00:00
Chris Lattner
92090188c3
Implement a FIXME, recusively reassociating
...
A*A*B + A*A*C --> A*(A*B+A*C) --> A*(A*(B+C))
This implements Reassociate/mul-factor3.ll
llvm-svn: 26757
2006-03-14 16:04:29 +00:00
Chris Lattner
9ccb2201b8
extract some code into a method, no functionality change
...
llvm-svn: 26755
2006-03-14 07:11:11 +00:00
Chris Lattner
0e3d81d8ff
Promote shifts by a constant to multiplies so that we can reassociate
...
(x<<1)+(y<<1) -> (X+Y)<<1. This implements
Transforms/Reassociate/shift-factor.ll
llvm-svn: 26753
2006-03-14 06:55:18 +00:00
Evan Cheng
692235499c
Added target lowering hooks which LSR consults to make more intelligent
...
transformation decisions.
llvm-svn: 26738
2006-03-13 23:14:23 +00:00
Jim Laskey
c741139c24
Handle the removal of the debug chain.
...
llvm-svn: 26729
2006-03-13 13:07:37 +00:00
Chris Lattner
a7d7a291d0
use autogenerated side-effect information
...
llvm-svn: 26673
2006-03-09 22:38:10 +00:00
Chris Lattner
67a978dc1d
fix a pasto
...
llvm-svn: 26627
2006-03-09 06:09:41 +00:00
Chris Lattner
256eff3ac6
Fix a miscompilation of 188.ammp with the new CFE. 188.ammp is accessing
...
arrays out of range in a horrible way, but we shouldn't break it anyway.
Details in the comments.
llvm-svn: 26606
2006-03-08 01:05:29 +00:00
Jim Laskey
eec3faecde
Switch to using a numeric id for anchors.
...
llvm-svn: 26598
2006-03-07 20:53:47 +00:00
Chris Lattner
c9039049c0
Fix ConstantMerge/2006-03-07-DontMergeDiffSections.ll, a problem Jim
...
hypotheticalized about, where we would incorrectly merge two globals in
different sections.
llvm-svn: 26597
2006-03-07 17:56:59 +00:00
Chris Lattner
8a548b3e7d
Teach the alignment handling code to look through constant expr casts and GEPs
...
llvm-svn: 26580
2006-03-07 01:28:57 +00:00
Chris Lattner
58fe521b5b
Teach instcombine to increase the alignment of memset/memcpy/memmove when
...
the pointer is known to come from either a global variable, alloca or
malloc. This allows us to compile this:
P = malloc(28);
memset(P, 0, 28);
into explicit stores on PPC instead of a memset call.
llvm-svn: 26577
2006-03-06 20:18:44 +00:00
Chris Lattner
43e9ec760b
Make vector narrowing more effective, implementing
...
Transforms/InstCombine/vec_narrow.ll. This add support for narrowing
extract_element(insertelement) also.
llvm-svn: 26538
2006-03-05 00:22:33 +00:00
Chris Lattner
7694fbc4bb
Add factoring of multiplications, e.g. turning A*A+A*B into A*(A+B).
...
Testcase here: Transforms/Reassociate/mulfactor.ll
llvm-svn: 26524
2006-03-04 09:31:13 +00:00
Chris Lattner
f526a4e5f6
Canonicalize (X+C1)*C2 -> X*C2+C1*C2
...
This implements Transforms/InstCombine/add.ll:test31
llvm-svn: 26519
2006-03-04 06:04:02 +00:00
Chris Lattner
45ee76ee68
Change this to work with renamed intrinsics.
...
llvm-svn: 26484
2006-03-03 01:34:17 +00:00
Chris Lattner
a22de4b7d3
Make this work with renamed intrinsics.
...
llvm-svn: 26482
2006-03-03 01:30:23 +00:00
Chris Lattner
092112baa6
Generalize the REM folding code to handle another case Nick Lewycky
...
pointed out: realize the AND can provide factors and look through Casts.
llvm-svn: 26469
2006-03-02 06:50:58 +00:00
Chris Lattner
74e3523663
Fix a regression in a patch from a couple of days ago. This fixes
...
Transforms/InstCombine/2006-02-28-Crash.ll
llvm-svn: 26427
2006-02-28 19:47:20 +00:00
Chris Lattner
684fc3dc9d
Implement rem.ll:test[7-9] and PR712
...
llvm-svn: 26415
2006-02-28 05:49:21 +00:00
Chris Lattner
63647f5028
Simplify some code now that the RHS of a rem can't be 0
...
llvm-svn: 26413
2006-02-28 05:40:55 +00:00
Chris Lattner
3b9fc06289
Rearrange some code, fold "rem X, 0", implementing rem.ll:test6
...
llvm-svn: 26411
2006-02-28 05:30:45 +00:00
Chris Lattner
792bfd8f28
Merge two almost-identical pieces of code.
...
Make this code more powerful by using ComputeMaskedBits instead of looking
for an AND operand. This lets us fold this:
int %test23(int %a) {
%tmp.1 = and int %a, 1
%tmp.2 = seteq int %tmp.1, 0
%tmp.3 = cast bool %tmp.2 to int ;; xor tmp1, 1
ret int %tmp.3
}
into: xor (and a, 1), 1
llvm-svn: 26396
2006-02-27 02:38:23 +00:00
Chris Lattner
c27bba037b
Fold (A^B) == A -> B == 0
...
and (A-B) == A -> B == 0
llvm-svn: 26394
2006-02-27 01:44:11 +00:00
Chris Lattner
80e2fa8a9d
Fold (X|C1)^C2 -> X^(C1|C2) when possible. This implements
...
InstCombine/or.ll:test23.
llvm-svn: 26385
2006-02-26 19:57:54 +00:00
Chris Lattner
304aeda827
Fix a problem that Nate noticed that boils down to an over conservative check
...
in the code that does "select C, (X+Y), (X-Y) --> (X+(select C, Y, (-Y)))".
We now compile this loop:
LBB1_1: ; no_exit
add r6, r2, r3
subf r3, r2, r3
cmpwi cr0, r2, 0
addi r7, r5, 4
lwz r2, 0(r5)
addi r4, r4, 1
blt cr0, LBB1_4 ; no_exit
LBB1_3: ; no_exit
mr r3, r6
LBB1_4: ; no_exit
cmpwi cr0, r4, 16
mr r5, r7
bne cr0, LBB1_1 ; no_exit
into this instead:
LBB1_1: ; no_exit
srawi r6, r2, 31
add r2, r2, r6
xor r6, r2, r6
addi r7, r5, 4
lwz r2, 0(r5)
addi r4, r4, 1
add r3, r3, r6
cmpwi cr0, r4, 16
mr r5, r7
bne cr0, LBB1_1 ; no_exit
llvm-svn: 26356
2006-02-24 18:05:58 +00:00