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1349 Commits

Author SHA1 Message Date
Chris Lattner
2a86f3b744 Implement Transforms/InstCombine/hoist_instr.ll 
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@30234 91177308-0d34-0410-b5e6-96231b3b80d8
 2006-09-09 22:02:56 +00:00
Chris Lattner
8e49e08f4b Turn div X, (Cond ? Y : 0) -> div X, Y 
This implements select.ll::test18.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@30230 91177308-0d34-0410-b5e6-96231b3b80d8
 2006-09-09 20:26:32 +00:00
Chris Lattner
e99c623e75 Throttle back tail duplication to avoid creating really ugly sequences of code. 
For Transforms/TailDup/if-tail-dup.ll, f.e., it produces:

_foo:
        movl 8(%esp), %eax
        movl 4(%esp), %ecx
        testl $1, %ecx
        je LBB1_2       #cond_next
LBB1_1: #cond_true
        movl $1, (%eax)
LBB1_2: #cond_next
        testl $2, %ecx
        je LBB1_4       #cond_next10
LBB1_3: #cond_true6
        movl $1, 4(%eax)
LBB1_4: #cond_next10
        testl $4, %ecx
        je LBB1_6       #cond_next18
LBB1_5: #cond_true14
        movl $1, 8(%eax)
LBB1_6: #cond_next18
        testl $8, %ecx
        je LBB1_8       #return
LBB1_7: #cond_true22
        movl $1, 12(%eax)
        ret
LBB1_8: #return
        ret

instead of:

_foo:
        movl 4(%esp), %eax
        testl $2, %eax
        sete %cl
        movl 8(%esp), %edx
        testl $1, %eax
        je LBB1_2       #cond_next
LBB1_1: #cond_true
        movl $1, (%edx)
        testb %cl, %cl
        jne LBB1_4      #cond_next10
        jmp LBB1_3      #cond_true6
LBB1_2: #cond_next
        testb %cl, %cl
        jne LBB1_4      #cond_next10
LBB1_3: #cond_true6
        movl $1, 4(%edx)
        testl $4, %eax
        je LBB1_6       #cond_next18
        jmp LBB1_5      #cond_true14
LBB1_4: #cond_next10
        testl $4, %eax
        je LBB1_6       #cond_next18
LBB1_5: #cond_true14
        movl $1, 8(%edx)
        testl $8, %eax
        je LBB1_8       #return
        jmp LBB1_7      #cond_true22
LBB1_6: #cond_next18
        testl $8, %eax
        je LBB1_8       #return
LBB1_7: #cond_true22
        movl $1, 12(%edx)
        ret
LBB1_8: #return
        ret


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@30158 91177308-0d34-0410-b5e6-96231b3b80d8
 2006-09-07 21:30:15 +00:00
Nick Lewycky
a3a68bde21 Improve handling of SelectInst. 
Reorder operations to remove duplicated work.
Fix to leave floating-point types out of the optimization.
Add tests to predsimplify.ll for SwitchInst and SelectInst handling.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@30055 91177308-0d34-0410-b5e6-96231b3b80d8
 2006-09-02 19:40:38 +00:00
Nick Lewycky
7218c28822 Don't confuse canonicalize and lookup. Fixes predsimplify.reg4.ll. Also 
corrects missing optimization opportunity removing cases from a switch.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@30009 91177308-0d34-0410-b5e6-96231b3b80d8
 2006-09-01 03:26:35 +00:00
Nick Lewycky
6e39c7ed1e Properties where both Values weren't in the union (as being equal to 
another Value) weren't being found by findProperties.

This fixes predsimplify.ll test6, a missed optimization opportunity.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@29991 91177308-0d34-0410-b5e6-96231b3b80d8
 2006-08-31 00:39:16 +00:00
Nick Lewycky
3947a76e21 Move to using the EquivalenceClass ADT. Removes SynSets. 
If a branch's condition has become a ConstantBool, simplify it immediately.
Removing the edge saves work and exposes up more optimization opportunities
in the pass.
Add support for SelectInst.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@29970 91177308-0d34-0410-b5e6-96231b3b80d8
 2006-08-30 02:46:48 +00:00
Devang Patel
4b8f36f106 Do not rely on std::sort and std::erase to get list of unique 
exit blocks. The output is dependent on addresses of basic block.

Add and use Loop::getUniqueExitBlocks.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@29966 91177308-0d34-0410-b5e6-96231b3b80d8
 2006-08-29 22:29:16 +00:00
Owen Anderson
d648e140a5 Clean up a bit. 
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@29950 91177308-0d34-0410-b5e6-96231b3b80d8
 2006-08-29 06:10:56 +00:00
Nick Lewycky
05450ae128 Add PredicateSimplifier pass. Collapses equal variables into one form 
and simplifies expressions. This implements the optimization described
in PR807.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@29947 91177308-0d34-0410-b5e6-96231b3b80d8
 2006-08-28 22:44:55 +00:00
Owen Anderson
59312b19a6 Make LoopUnroll fold excessive BasicBlocks. This results in a significant speedup of 
gccas on 252.eon


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@29936 91177308-0d34-0410-b5e6-96231b3b80d8
 2006-08-28 02:09:46 +00:00
Chris Lattner
7f8897f22e eliminate RegisterOpt. It does the same thing as RegisterPass. 
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@29925 91177308-0d34-0410-b5e6-96231b3b80d8
 2006-08-27 22:42:52 +00:00
Chris Lattner
a4f0b3a084 s|llvm/Support/Visibility.h|llvm/Support/Compiler.h| 
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@29911 91177308-0d34-0410-b5e6-96231b3b80d8
 2006-08-27 12:54:02 +00:00
Owen Anderson
203572552d Fix a crash related to updating Phi nodes in the original header block. This was 
causing a crash in 175.vpr


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@29887 91177308-0d34-0410-b5e6-96231b3b80d8
 2006-08-25 22:13:55 +00:00
Owen Anderson
eb70591492 Add an assertion to check that we're really preserving LCSSA. 
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@29886 91177308-0d34-0410-b5e6-96231b3b80d8
 2006-08-25 22:12:36 +00:00
Owen Anderson
ac12322710 Reapply the indvars patch, since nothing blew up last night. 
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@29874 91177308-0d34-0410-b5e6-96231b3b80d8
 2006-08-25 17:41:25 +00:00
Owen Anderson
b397d81f03 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.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@29868 91177308-0d34-0410-b5e6-96231b3b80d8
 2006-08-25 03:45:57 +00:00
Owen Anderson
8a24749cb8 Specify that indvars actually preserve LCSSA. This has been done for a while, but I 
forgot to put in the analysis usage.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@29867 91177308-0d34-0410-b5e6-96231b3b80d8
 2006-08-25 03:32:13 +00:00
Owen Anderson
3b53c4ee91 Implement unrolling of multiblock loops. This significantly improves the 
utility of the LoopUnroll pass.

Also, add a testcase for multiblock-loop unrolling.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@29859 91177308-0d34-0410-b5e6-96231b3b80d8
 2006-08-24 21:28:19 +00:00
Reid Spencer
47a53ac726 Fix a grammaro in a comment. 
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@29765 91177308-0d34-0410-b5e6-96231b3b80d8
 2006-08-18 09:01:07 +00:00
Chris Lattner
df32aac51b Handle single-entry PHI nodes correctly. This fixes PR877 and 
Transforms/CondProp/2006-08-14-SingleEntryPhiCrash.ll


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@29673 91177308-0d34-0410-b5e6-96231b3b80d8
 2006-08-14 21:38:05 +00:00
Chris Lattner
7e79b3898d 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. :)


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@29493 91177308-0d34-0410-b5e6-96231b3b80d8
 2006-08-03 06:34:50 +00:00
Chris Lattner
ec3c411de8 Minor comment tweaks 
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@29226 91177308-0d34-0410-b5e6-96231b3b80d8
 2006-07-20 19:06:16 +00:00
Owen Anderson
10d9d9f27c Add an assertion. 
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@29199 91177308-0d34-0410-b5e6-96231b3b80d8
 2006-07-19 05:48:45 +00:00
Owen Anderson
2698a08c23 Make LoopUnroll not die on LCSSA Phis. This makes lencod work again. 
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@29198 91177308-0d34-0410-b5e6-96231b3b80d8
 2006-07-19 05:45:14 +00:00
Owen Anderson
db5b9cfd86 Fix a error that hadn't yet cause any problems, but I'm sure it would have 
somewhere down the road.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@29197 91177308-0d34-0410-b5e6-96231b3b80d8
 2006-07-19 03:51:48 +00:00
Evan Cheng
31e773147b Only reuse a previous IV if it would not require a type conversion. 
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@29186 91177308-0d34-0410-b5e6-96231b3b80d8
 2006-07-18 19:07:58 +00:00
Owen Anderson
c1be492f94 Hopefully the final attempt at making IndVars preserve LCSSA. 
This should fix PR 831.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@29141 91177308-0d34-0410-b5e6-96231b3b80d8
 2006-07-14 18:49:15 +00:00
Chris Lattner
262041892d Revert this patch temporarily until PR831 is fixed. 
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@29134 91177308-0d34-0410-b5e6-96231b3b80d8
 2006-07-13 19:05:20 +00:00
Owen Anderson
bcfb913df0 IndVars now (correctly) preserves LCSSA form. 
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@29126 91177308-0d34-0410-b5e6-96231b3b80d8
 2006-07-12 21:29:14 +00:00
Chris Lattner
ed36b2f1c2 Silence a warning produced in assertions-disabled mode 
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@29108 91177308-0d34-0410-b5e6-96231b3b80d8
 2006-07-11 18:31:26 +00:00
Owen Anderson
4a8aadd1f5 Revert my indvars changes because they were breaking things. Unfortunately this 
didn't start showing up until after the recent instcombine fixes.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@29102 91177308-0d34-0410-b5e6-96231b3b80d8
 2006-07-11 07:25:33 +00:00
Owen Anderson
b64ab8769e Add a comment, and fix a typo that broke the build. 
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@29094 91177308-0d34-0410-b5e6-96231b3b80d8
 2006-07-10 22:15:25 +00:00
Owen Anderson
7e05714a10 Don't indent the entire function. 
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@29093 91177308-0d34-0410-b5e6-96231b3b80d8
 2006-07-10 22:03:18 +00:00
Chris Lattner
6423d4c64a Recognize 16-bit bswaps by relaxing overconstrained pattern. 
This implements Transforms/InstCombine/bswap.ll:test[34].


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@29087 91177308-0d34-0410-b5e6-96231b3b80d8
 2006-07-10 20:25:24 +00:00
Owen Anderson
d1b78a12ef Make instcombine not remove Phi nodes when LCSSA is live. 
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@29083 91177308-0d34-0410-b5e6-96231b3b80d8
 2006-07-10 19:03:49 +00:00
Chris Lattner
9525528a7d Use hidden visibility to make symbols in an anonymous namespace get 
dropped.  This shrinks libllvmgcc.dylib another 67K


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@28975 91177308-0d34-0410-b5e6-96231b3b80d8
 2006-06-28 23:17:24 +00:00
Chris Lattner
f4b546110c Shrink libllvmgcc.dylib by another 23K 
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@28972 91177308-0d34-0410-b5e6-96231b3b80d8
 2006-06-28 22:08:15 +00:00
Owen Anderson
372994be25 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.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@28962 91177308-0d34-0410-b5e6-96231b3b80d8
 2006-06-28 17:47:50 +00:00
Chris Lattner
d228018396 Fix Transforms/InstCombine/2006-06-28-infloop.ll 
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@28961 91177308-0d34-0410-b5e6-96231b3b80d8
 2006-06-28 17:34:50 +00:00
Chris Lattner
daa2bf9a19 Don't unswitch really large loops even if they are mostly filled with empty 
blocks.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@28959 91177308-0d34-0410-b5e6-96231b3b80d8
 2006-06-28 16:38:55 +00:00
Andrew Lenharth
b8e604c29a 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 )


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@28953 91177308-0d34-0410-b5e6-96231b3b80d8
 2006-06-28 01:01:52 +00:00
Owen Anderson
bef8508737 Fix for 2006-06-27-DeadSwitchCase.ll 
Be more careful when updating Phi nodes after eliminating dead switch cases.  Fix
proposed by Chris.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@28947 91177308-0d34-0410-b5e6-96231b3b80d8
 2006-06-27 22:26:09 +00:00
Owen Anderson
f9b238e93d De-pessimize the handling of LCSSA Phi nodes in IndVarSimplify. Hopefully this 
will make Shootout-C/nestedloop faster.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@28924 91177308-0d34-0410-b5e6-96231b3b80d8
 2006-06-27 02:17:08 +00:00
Chris Lattner
3c80a51cfd random code cleanups, no functionality change 
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@28914 91177308-0d34-0410-b5e6-96231b3b80d8
 2006-06-26 19:10:05 +00:00
Owen Anderson
2b67f07d2b 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.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@28912 91177308-0d34-0410-b5e6-96231b3b80d8
 2006-06-26 07:44:36 +00:00
Chris Lattner
eb83f4e6cd 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.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@28850 91177308-0d34-0410-b5e6-96231b3b80d8
 2006-06-17 01:02:31 +00:00
Chris Lattner
afe91a5f26 Implement Transforms/InstCombine/bswap.ll, turning common shift/and/or bswap 
idioms into bswap intrinsics.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@28803 91177308-0d34-0410-b5e6-96231b3b80d8
 2006-06-15 19:07:26 +00:00
Chris Lattner
f7a1212850 Fix Transforms/LoopUnswitch/2006-06-13-SingleEntryPHI.ll, a loop unswitch 
bug exposed by the recent lcssa work.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@28779 91177308-0d34-0410-b5e6-96231b3b80d8
 2006-06-14 04:46:17 +00:00
Owen Anderson
6edf399bb4 Reapply my 6/9 changes. The bug Evan saw no longer occurs. 
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@28759 91177308-0d34-0410-b5e6-96231b3b80d8
 2006-06-12 21:49:21 +00:00
Evan Cheng
b9b2b309d3 Back out Owen's 6/9 changes. They broke MultiSource/Benchmarks/Prolangs-C/bison (and perhaps others). 
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@28747 91177308-0d34-0410-b5e6-96231b3b80d8
 2006-06-11 09:32:57 +00:00
Owen Anderson
fcaf345c88 Add LCSSA as a requirement for LoopUnswitch, and assert that LoopUnswitch preserves 
LCSSA.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@28739 91177308-0d34-0410-b5e6-96231b3b80d8
 2006-06-09 18:40:32 +00:00
Evan Cheng
86c75d3113 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.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@28735 91177308-0d34-0410-b5e6-96231b3b80d8
 2006-06-09 00:12:42 +00:00
Reid Spencer
6296b3cac5 Fix a spello in a comment. 
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@28714 91177308-0d34-0410-b5e6-96231b3b80d8
 2006-06-07 21:24:10 +00:00
Chris Lattner
18a4af2ba6 Fix a bug in a recent patch. This fixes UnitTests/Vector/Altivec/casts.c on 
PPC/altivec


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@28698 91177308-0d34-0410-b5e6-96231b3b80d8
 2006-06-06 22:26:02 +00:00
Chris Lattner
0c1262c9f9 Remove unneeded hook. Patch by Anton K. Thanks! 
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@28664 91177308-0d34-0410-b5e6-96231b3b80d8
 2006-06-02 19:11:46 +00:00
Chris Lattner
5180b29cb0 Silence a -pedantic warning. 
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@28632 91177308-0d34-0410-b5e6-96231b3b80d8
 2006-06-01 17:16:21 +00:00
Chris Lattner
13d4ab4009 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.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@28600 91177308-0d34-0410-b5e6-96231b3b80d8
 2006-05-31 21:14:00 +00:00
Chris Lattner
b4db97ffa7 Implement Transforms/InstCombine/store.ll:test2. 
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@28503 91177308-0d34-0410-b5e6-96231b3b80d8
 2006-05-26 19:19:20 +00:00
Chris Lattner
7b2e2792d6 Transform things like (splat(splat)) -> splat 
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@28490 91177308-0d34-0410-b5e6-96231b3b80d8
 2006-05-26 00:29:06 +00:00
Chris Lattner
863bcff183 Introduce a helper function that simplifies interpretation of shuffle masks. 
No functionality change.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@28489 91177308-0d34-0410-b5e6-96231b3b80d8
 2006-05-25 23:48:38 +00:00
Chris Lattner
01575b7315 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


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@28487 91177308-0d34-0410-b5e6-96231b3b80d8
 2006-05-25 23:24:33 +00:00
Chris Lattner
73fa49d697 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]


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@28485 91177308-0d34-0410-b5e6-96231b3b80d8
 2006-05-25 22:53:38 +00:00
Chris Lattner
01859e8853 Silence a bogus gcc warning 
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@28422 91177308-0d34-0410-b5e6-96231b3b80d8
 2006-05-20 23:14:03 +00:00
Evan Cheng
3e246dd084 Backing out last check-in for now. It's causing an infinite loop gccas lencode. 
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@28284 91177308-0d34-0410-b5e6-96231b3b80d8
 2006-05-14 06:46:03 +00:00
Chris Lattner
033aaaf451 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.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@28275 91177308-0d34-0410-b5e6-96231b3b80d8
 2006-05-13 02:16:08 +00:00
Chris Lattner
70074e00a2 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.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@28273 91177308-0d34-0410-b5e6-96231b3b80d8
 2006-05-13 02:06:03 +00:00
Chris Lattner
8c8c66a8cd 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.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@28224 91177308-0d34-0410-b5e6-96231b3b80d8
 2006-05-11 17:11:52 +00:00
Chris Lattner
f4f5a77fdc 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).


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@28215 91177308-0d34-0410-b5e6-96231b3b80d8
 2006-05-10 19:00:36 +00:00
Chris Lattner
33a6113995 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


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@28141 91177308-0d34-0410-b5e6-96231b3b80d8
 2006-05-06 09:00:16 +00:00
Chris Lattner
581a7ad7c9 Fix an infinite loop compiling oggenc last night. 
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@28128 91177308-0d34-0410-b5e6-96231b3b80d8
 2006-05-05 20:51:30 +00:00
Chris Lattner
6fc205fc44 Implement InstCombine/cast.ll:test29 
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@28126 91177308-0d34-0410-b5e6-96231b3b80d8
 2006-05-05 06:39:07 +00:00
Chris Lattner
e3158308e0 Fix Transforms/InstCombine/2006-05-04-DemandedBitCrash.ll 
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@28101 91177308-0d34-0410-b5e6-96231b3b80d8
 2006-05-04 17:33:35 +00:00
Chris Lattner
94046b4d10 Fix InstCombine/2006-04-28-ShiftShiftLongLong.ll 
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@28019 91177308-0d34-0410-b5e6-96231b3b80d8
 2006-04-28 22:21:41 +00:00
Chris Lattner
ae74f55552 Fix Transforms/Reassociate/2006-04-27-ReassociateVector.ll 
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@28007 91177308-0d34-0410-b5e6-96231b3b80d8
 2006-04-28 04:14:49 +00:00
Chris Lattner
d929f06f4d Add support for inserting undef into a vector. This implements 
Transforms/InstCombine/vec_insert_to_shuffle.ll


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@27997 91177308-0d34-0410-b5e6-96231b3b80d8
 2006-04-27 21:14:21 +00:00
Chris Lattner
df4f226cdc Fix Transforms/ScalarRepl/2006-04-20-PromoteCrash.ll 
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@27912 91177308-0d34-0410-b5e6-96231b3b80d8
 2006-04-20 20:48:50 +00:00
Andrew Lenharth
7a31b975fb Make code match cvs commit message :) 
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@27881 91177308-0d34-0410-b5e6-96231b3b80d8
 2006-04-20 15:41:37 +00:00
Andrew Lenharth
8117f9a40e 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.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@27880 91177308-0d34-0410-b5e6-96231b3b80d8
 2006-04-20 14:56:47 +00:00
Chris Lattner
fd6bdf0b0f Turn x86 unaligned load/store intrinsics into aligned load/store instructions 
if the pointer is known aligned.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@27781 91177308-0d34-0410-b5e6-96231b3b80d8
 2006-04-17 22:26:56 +00:00
Chris Lattner
7f6cc0ccb5 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


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@27728 91177308-0d34-0410-b5e6-96231b3b80d8
 2006-04-16 00:51:47 +00:00
Chris Lattner
706126dac1 Canonicalize shuffle(undef,x,mask) -> shuffle(x, undef,mask'). 
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@27727 91177308-0d34-0410-b5e6-96231b3b80d8
 2006-04-16 00:03:56 +00:00
Chris Lattner
efb47359ff significant cleanups to code that uses insert/extractelt heavily. This builds 
maximal shuffles out of them where possible.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@27717 91177308-0d34-0410-b5e6-96231b3b80d8
 2006-04-15 01:39:45 +00:00
Chris Lattner
de6df88529 Teach scalarrepl to promote unions of vectors and floats, producing 
insert/extractelement operations.  This implements
Transforms/ScalarRepl/vector_promote.ll


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@27710 91177308-0d34-0410-b5e6-96231b3b80d8
 2006-04-14 21:42:41 +00:00
Reid Spencer
ad2072643a Get rid of a signed/unsigned compare warning. 
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@27625 91177308-0d34-0410-b5e6-96231b3b80d8
 2006-04-12 19:28:15 +00:00
Chris Lattner
9fb9213083 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.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@27620 91177308-0d34-0410-b5e6-96231b3b80d8
 2006-04-12 18:09:35 +00:00
Chris Lattner
389a6f58f7 Implement vec_shuffle.ll:test3 
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@27573 91177308-0d34-0410-b5e6-96231b3b80d8
 2006-04-10 23:06:36 +00:00
Chris Lattner
a844fc4cb0 Implement InstCombine/vec_shuffle.ll:test[12] 
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@27571 91177308-0d34-0410-b5e6-96231b3b80d8
 2006-04-10 22:45:52 +00:00
Chris Lattner
543abdf1d0 Add supprot for shufflevector 
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@27513 91177308-0d34-0410-b5e6-96231b3b80d8
 2006-04-08 01:19:12 +00:00
Chris Lattner
e2ed057562 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


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@27452 91177308-0d34-0410-b5e6-96231b3b80d8
 2006-04-06 19:19:17 +00:00
Chris Lattner
4132afb0d2 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]


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@27355 91177308-0d34-0410-b5e6-96231b3b80d8
 2006-04-02 05:43:13 +00:00
Chris Lattner
a1c3538537 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]


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@27353 91177308-0d34-0410-b5e6-96231b3b80d8
 2006-04-02 05:37:12 +00:00
Chris Lattner
82ed58f9c4 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


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@27352 91177308-0d34-0410-b5e6-96231b3b80d8
 2006-04-02 05:30:25 +00:00
Chris Lattner
ae1ab3989c Fix InstCombine/2006-04-01-InfLoop.ll 
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@27330 91177308-0d34-0410-b5e6-96231b3b80d8
 2006-04-01 22:05:01 +00:00
Chris Lattner
64daab56c2 Fold A^(B&A) -> (B&A)^A 
Fold (B&A)^A == ~B & A

This implements InstCombine/xor.ll:test2[56]


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@27328 91177308-0d34-0410-b5e6-96231b3b80d8
 2006-04-01 08:03:55 +00:00
Chris Lattner
6e6b0da303 If we can look through vector operations to find the scalar version of an 
extract_element'd value, do so.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@27323 91177308-0d34-0410-b5e6-96231b3b80d8
 2006-03-31 23:01:56 +00:00
Chris Lattner
1f13c88939 extractelement(undef,x) -> undef 
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@27300 91177308-0d34-0410-b5e6-96231b3b80d8
 2006-03-31 18:25:14 +00:00
Chris Lattner
df084ff78b Fix Transforms/InstCombine/2006-03-30-ExtractElement.ll 
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@27261 91177308-0d34-0410-b5e6-96231b3b80d8
 2006-03-30 22:02:40 +00:00
Chris Lattner
98509ef3c7 Don't crash on packed logical ops 
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@27125 91177308-0d34-0410-b5e6-96231b3b80d8
 2006-03-25 21:58:26 +00:00
Chris Lattner
98d9811db2 Fix spello 
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@27052 91177308-0d34-0410-b5e6-96231b3b80d8
 2006-03-24 07:14:34 +00:00
Chris Lattner
0f862e50ae add the actual cost to the debug info 
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@27051 91177308-0d34-0410-b5e6-96231b3b80d8
 2006-03-24 07:14:00 +00:00
Jim Laskey
930ac0606c Can't combine anymore - we don't have a chain through llvm.dbg intrinsics. 
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@26992 91177308-0d34-0410-b5e6-96231b3b80d8
 2006-03-23 18:10:42 +00:00
Chris Lattner
035c6a2356 silence a bogus gcc warning 
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@26953 91177308-0d34-0410-b5e6-96231b3b80d8
 2006-03-22 17:27:24 +00:00
Chris Lattner
273f202890 Teach cee to propagate through switch statements. This implements 
Transforms/CorrelatedExprs/switch.ll

Patch contributed by Eric Kidd!


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@26872 91177308-0d34-0410-b5e6-96231b3b80d8
 2006-03-19 19:37:24 +00:00
Evan Cheng
21495775e7 - 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.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@26841 91177308-0d34-0410-b5e6-96231b3b80d8
 2006-03-18 08:03:12 +00:00
Evan Cheng
4496a50deb Sort StrideOrder so we can process the smallest strides first. This allows 
for more IV reuses.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@26837 91177308-0d34-0410-b5e6-96231b3b80d8
 2006-03-18 00:44:49 +00:00
Evan Cheng
eb8f9e2297 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.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@26828 91177308-0d34-0410-b5e6-96231b3b80d8
 2006-03-17 19:52:23 +00:00
Evan Cheng
d1d6b5cce2 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.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@26803 91177308-0d34-0410-b5e6-96231b3b80d8
 2006-03-16 21:53:05 +00:00
Chris Lattner
e9efecbf47 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


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@26757 91177308-0d34-0410-b5e6-96231b3b80d8
 2006-03-14 16:04:29 +00:00
Chris Lattner
895b392269 extract some code into a method, no functionality change 
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@26755 91177308-0d34-0410-b5e6-96231b3b80d8
 2006-03-14 07:11:11 +00:00
Chris Lattner
22a66c41f3 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


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@26753 91177308-0d34-0410-b5e6-96231b3b80d8
 2006-03-14 06:55:18 +00:00
Evan Cheng
d277f2c669 Added target lowering hooks which LSR consults to make more intelligent 
transformation decisions.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@26738 91177308-0d34-0410-b5e6-96231b3b80d8
 2006-03-13 23:14:23 +00:00
Chris Lattner
25de486263 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.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@26606 91177308-0d34-0410-b5e6-96231b3b80d8
 2006-03-08 01:05:29 +00:00
Chris Lattner
51c26e911a Teach the alignment handling code to look through constant expr casts and GEPs 
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@26580 91177308-0d34-0410-b5e6-96231b3b80d8
 2006-03-07 01:28:57 +00:00
Chris Lattner
95a959dc1a 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.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@26577 91177308-0d34-0410-b5e6-96231b3b80d8
 2006-03-06 20:18:44 +00:00
Chris Lattner
220b0cf3e4 Make vector narrowing more effective, implementing 
Transforms/InstCombine/vec_narrow.ll.  This add support for narrowing
extract_element(insertelement) also.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@26538 91177308-0d34-0410-b5e6-96231b3b80d8
 2006-03-05 00:22:33 +00:00
Chris Lattner
e5022fe4cd Add factoring of multiplications, e.g. turning A*A+A*B into A*(A+B). 
Testcase here: Transforms/Reassociate/mulfactor.ll


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@26524 91177308-0d34-0410-b5e6-96231b3b80d8
 2006-03-04 09:31:13 +00:00
Chris Lattner
ab51f3fa96 Canonicalize (X+C1)*C2 -> X*C2+C1*C2 
This implements Transforms/InstCombine/add.ll:test31


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@26519 91177308-0d34-0410-b5e6-96231b3b80d8
 2006-03-04 06:04:02 +00:00
Chris Lattner
21959390c1 Change this to work with renamed intrinsics. 
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@26484 91177308-0d34-0410-b5e6-96231b3b80d8
 2006-03-03 01:34:17 +00:00
Chris Lattner
db3f873bd8 Generalize the REM folding code to handle another case Nick Lewycky 
pointed out: realize the AND can provide factors and look through Casts.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@26469 91177308-0d34-0410-b5e6-96231b3b80d8
 2006-03-02 06:50:58 +00:00
Chris Lattner
06e1e25368 Fix a regression in a patch from a couple of days ago. This fixes 
Transforms/InstCombine/2006-02-28-Crash.ll


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@26427 91177308-0d34-0410-b5e6-96231b3b80d8
 2006-02-28 19:47:20 +00:00
Chris Lattner
9794392781 Implement rem.ll:test[7-9] and PR712 
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@26415 91177308-0d34-0410-b5e6-96231b3b80d8
 2006-02-28 05:49:21 +00:00
Chris Lattner
6c9951b0da Simplify some code now that the RHS of a rem can't be 0 
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@26413 91177308-0d34-0410-b5e6-96231b3b80d8
 2006-02-28 05:40:55 +00:00
Chris Lattner
19ccd5c757 Rearrange some code, fold "rem X, 0", implementing rem.ll:test6 
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@26411 91177308-0d34-0410-b5e6-96231b3b80d8
 2006-02-28 05:30:45 +00:00
Chris Lattner
3e88a4d700 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


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@26396 91177308-0d34-0410-b5e6-96231b3b80d8
 2006-02-27 02:38:23 +00:00
Chris Lattner
26ab9a9218 Fold (A^B) == A -> B == 0 
and  (A-B) == A  ->  B == 0


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@26394 91177308-0d34-0410-b5e6-96231b3b80d8
 2006-02-27 01:44:11 +00:00
Chris Lattner
02bd1b3e94 Fold (X|C1)^C2 -> X^(C1|C2) when possible. This implements 
InstCombine/or.ll:test23.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@26385 91177308-0d34-0410-b5e6-96231b3b80d8
 2006-02-26 19:57:54 +00:00
Chris Lattner
97f37a439c 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


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@26356 91177308-0d34-0410-b5e6-96231b3b80d8
 2006-02-24 18:05:58 +00:00
Chris Lattner
f8bf116f80 Fix Regression/Transforms/LoopUnswitch/2006-02-22-UnswitchCrash.ll, which 
caused SPASS to fail building last night.

We can't trivially unswitch a loop if the exit block has phi nodes in it,
because we don't know which predecessor to use.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@26320 91177308-0d34-0410-b5e6-96231b3b80d8
 2006-02-22 23:55:00 +00:00
Chris Lattner
bd28e3f8ef Add some comments, simplify some code, and fix a bug that caused rewriting 
to rewrite with the wrong value.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@26311 91177308-0d34-0410-b5e6-96231b3b80d8
 2006-02-22 06:37:14 +00:00
Chris Lattner
a6fc94b71e improved support for branch folding, still not enabled. 
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@26289 91177308-0d34-0410-b5e6-96231b3b80d8
 2006-02-18 07:57:38 +00:00
Jeff Cohen
bce4805d6f Fix bugs identified by VC++. 
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@26287 91177308-0d34-0410-b5e6-96231b3b80d8
 2006-02-18 03:20:33 +00:00
Chris Lattner
db41024a85 Implement deletion of dead blocks, currently disabled. 
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@26285 91177308-0d34-0410-b5e6-96231b3b80d8
 2006-02-18 02:42:34 +00:00
Chris Lattner
caf4893536 a previous patch completely disabled trivial unswitching, this fixees it. 
Thanks to nate for pointing this out :)


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@26280 91177308-0d34-0410-b5e6-96231b3b80d8
 2006-02-18 01:32:04 +00:00
Chris Lattner
f4412d890d initial trivial support for folding branches that have now-constant destinations. 
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@26279 91177308-0d34-0410-b5e6-96231b3b80d8
 2006-02-18 01:27:45 +00:00
Chris Lattner
25cae0fd1c When unswitching a loop, make sure to update loop info with exit blocks in 
the right loop.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@26277 91177308-0d34-0410-b5e6-96231b3b80d8
 2006-02-18 00:55:32 +00:00
Chris Lattner
0017d480cc Fix loops where the header has an exit, fixing a loop-unswitch crash on crafty 
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@26258 91177308-0d34-0410-b5e6-96231b3b80d8
 2006-02-17 06:39:56 +00:00
Chris Lattner
52221f7b16 start of some new simplification code, not thoroughly tested, use at your own 
risk :)


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@26248 91177308-0d34-0410-b5e6-96231b3b80d8
 2006-02-17 00:31:07 +00:00
Nate Begeman
368e18d56a Rework the SelectionDAG-based implementations of SimplifyDemandedBits 
and ComputeMaskedBits to match the new improved versions in instcombine.
Tested against all of multisource/benchmarks on ppc.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@26238 91177308-0d34-0410-b5e6-96231b3b80d8
 2006-02-16 21:11:51 +00:00
Chris Lattner
10cd9bbde7 Change SplitBlock to increment a BasicBlock::iterator, not an Instruction*. Apparently they do different things :) 
This fixes a testcase that nate reduced from spass.

Also included are a couple minor code changes that don't affect the generated
code at all.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@26235 91177308-0d34-0410-b5e6-96231b3b80d8
 2006-02-16 19:36:22 +00:00
Jeff Cohen
21c107ab0f Fix VC++ warning. 
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@26228 91177308-0d34-0410-b5e6-96231b3b80d8
 2006-02-16 04:07:37 +00:00
Chris Lattner
f17c42d409 fix a bug where we unswitched the wrong way 
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@26225 91177308-0d34-0410-b5e6-96231b3b80d8
 2006-02-16 01:24:41 +00:00
Chris Lattner
a48654ef23 Implement trivial unswitching for switch stmts. This allows us to trivial 
unswitch this loop on 2 before sweating to unswitch on 1/3.

void test4(int N, int i, int C, int*P, int*Q) {
  int j;
  for (j = 0; j < N; ++j) {
    switch (C) {                // general unswitching.
    default: P[i+j] = 0; break;
    case 1: Q[i+j] = 0; break;
    case 3: P[i+j] = Q[i+j]; break;
    case 2: break;              //  TRIVIAL UNSWITCH on C==2
    }
  }
}


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@26223 91177308-0d34-0410-b5e6-96231b3b80d8
 2006-02-15 22:52:05 +00:00
Chris Lattner
4e1323969c make "trivial" unswitching significantly more general. It can now handle 
this for example:

  for (j = 0; j < N; ++j) {     // trivial unswitch
    if (C)
      P[i+j] = 0;
  }

turning it into the obvious code without bothering to duplicate an empty loop.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@26220 91177308-0d34-0410-b5e6-96231b3b80d8
 2006-02-15 22:03:36 +00:00
Chris Lattner
3fdde110eb Checking the wrong value. This caused us to emit silly code like 
Y = seteq bool X, true
instead of just using X :)


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@26215 91177308-0d34-0410-b5e6-96231b3b80d8
 2006-02-15 19:05:52 +00:00
Chris Lattner
6d9d13d2e4 more refactoring, no functionality change. 
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@26194 91177308-0d34-0410-b5e6-96231b3b80d8
 2006-02-15 01:44:42 +00:00
Chris Lattner
fed5d9dbd3 pull some code out into a function 
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@26191 91177308-0d34-0410-b5e6-96231b3b80d8
 2006-02-15 00:07:43 +00:00
Chris Lattner
3dd4c402de Use statistics to keep track of what flavors of loops we are unswitching 
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@26157 91177308-0d34-0410-b5e6-96231b3b80d8
 2006-02-14 01:01:41 +00:00
Chris Lattner
2082ad9b41 Implement Instcombine/and.ll:test34 
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@26155 91177308-0d34-0410-b5e6-96231b3b80d8
 2006-02-13 23:07:23 +00:00
Chris Lattner
f345fe4d9a If any of the sign extended bits are demanded, the input sign bit is demanded 
for a sign extension.

This fixes InstCombine/2006-02-13-DemandedMiscompile.ll and Ptrdist/bc.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@26152 91177308-0d34-0410-b5e6-96231b3b80d8
 2006-02-13 22:41:07 +00:00
Chris Lattner
c15637bafc Be careful not to request or look at bits shifted in from outside the size 
of the input.  This fixes the mediabench/gsm/toast failure last night.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@26138 91177308-0d34-0410-b5e6-96231b3b80d8
 2006-02-13 06:09:08 +00:00
Chris Lattner
8d6bbdbbcb remove some more dead special case code 
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@26135 91177308-0d34-0410-b5e6-96231b3b80d8
 2006-02-12 08:07:37 +00:00
Chris Lattner
f8c36f502b Eliminate special case hacks that are superceded by general purpose hacks 
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@26134 91177308-0d34-0410-b5e6-96231b3b80d8
 2006-02-12 08:02:11 +00:00
Chris Lattner
bf5d8a8270 Three changes: 
1. Teach GetConstantInType to handle boolean constants.
2. Teach instcombine to fold (compare X, CST) when X has known 0/1 bits.
   Testcase here: set.ll:test22
3. Improve the "(X >> c1) & C2 == 0" folding code to allow a noop cast
   between the shift and and.  More aggressive bitfolding for other reasons
   was turning signed shr's into unsigned shr's, leaving the noop cast in
   the way.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@26131 91177308-0d34-0410-b5e6-96231b3b80d8
 2006-02-12 02:07:56 +00:00
Chris Lattner
255d8919b6 Port the recent innovations in ComputeMaskedBits to SimplifyDemandedBits. 
This allows us to simplify on conditions where bits are not known, but they
are not demanded either!  This also fixes a couple of bugs in
ComputeMaskedBits that were exposed during this work.

In the future, swaths of instcombine should be removed, as this code
subsumes a bunch of ad-hockery.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@26122 91177308-0d34-0410-b5e6-96231b3b80d8
 2006-02-11 09:31:47 +00:00
Chris Lattner
c23580969f implement unswitching of loops with switch stmts and selects in them 
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@26114 91177308-0d34-0410-b5e6-96231b3b80d8
 2006-02-11 00:43:37 +00:00
Chris Lattner
e825593bf2 Update PHI nodes in successors of exit blocks. 
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@26113 91177308-0d34-0410-b5e6-96231b3b80d8
 2006-02-10 23:26:14 +00:00
Chris Lattner
b2bc315eac Reform the unswitching code in terms of edge splitting, not block splitting. 
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@26112 91177308-0d34-0410-b5e6-96231b3b80d8
 2006-02-10 23:16:39 +00:00
Chris Lattner
81be2e961b Fix a case where UnswitchTrivialCondition broke critical edges with 
phi's in the successors


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@26108 91177308-0d34-0410-b5e6-96231b3b80d8
 2006-02-10 19:08:15 +00:00
Chris Lattner
708e1a5c9c add some notes, move some code around. Implement unswitching of loops 
with branches on partially invariant computations.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@26104 91177308-0d34-0410-b5e6-96231b3b80d8
 2006-02-10 02:30:37 +00:00
Chris Lattner
dd3ee6d086 Move code around to be more logical, no functionality change. 
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@26103 91177308-0d34-0410-b5e6-96231b3b80d8
 2006-02-10 02:01:22 +00:00
Chris Lattner
4d1ca946ea When unswitching a trivial loop, do admit we are doing it! :) 
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@26102 91177308-0d34-0410-b5e6-96231b3b80d8
 2006-02-10 01:36:35 +00:00
Chris Lattner
4c41d49a92 Implement unconditional unswitching of 'trivial' loops, those loops that contain 
branches in their entry block that control whether or not the loop is a noop or not.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@26101 91177308-0d34-0410-b5e6-96231b3b80d8
 2006-02-10 01:24:09 +00:00
Chris Lattner
f4f5f4e56f Simplify control flow a bit, note that unswitch preserves canonical loop form 
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@26098 91177308-0d34-0410-b5e6-96231b3b80d8
 2006-02-09 22:15:42 +00:00
Chris Lattner
e487abbfbf Make the threshold a parameter 
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@26093 91177308-0d34-0410-b5e6-96231b3b80d8
 2006-02-09 20:15:48 +00:00
Chris Lattner
2f4b898e8c Simplify the loop-unswitch pass, by not even trying to unswitch loops with 
uses of loop values outside the loop.  We need loop-closed SSA form to do
this right, or to use SSA rewriting if we really care.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@26089 91177308-0d34-0410-b5e6-96231b3b80d8
 2006-02-09 19:14:52 +00:00
Chris Lattner
9a4cacb7c2 Fix 80-column violations 
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@26088 91177308-0d34-0410-b5e6-96231b3b80d8
 2006-02-09 07:41:14 +00:00
Chris Lattner
68d5ff2b83 Enhance MVIZ in three ways: 
1. Teach it new tricks: in particular how to propagate through signed shr and sexts.
2. Teach it to return a bitset of known-1 and known-0 bits, instead of just zero.
3. Teach instcombine (AND X, C) to fold when we know all C bits of X.

This implements Regression/Transforms/InstCombine/bittest.ll, and allows
future things to be simplified.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@26087 91177308-0d34-0410-b5e6-96231b3b80d8
 2006-02-09 07:38:58 +00:00
Chris Lattner
7560c3af83 Simplify some code, reducing calls to MaskedValueIsZero. Implement a minor 
optimization where we reduce the number of bits in AND masks when possible.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@26056 91177308-0d34-0410-b5e6-96231b3b80d8
 2006-02-08 07:34:50 +00:00
Chris Lattner
9ca96410fc Use EraseInstFromFunction in a few cases to put the uses of the removed 
instruction onto the worklist (in case they are now dead).

Add a really trivial local DSE implementation to help out bitfield code.
We now fold this:

struct S {
    unsigned char a : 1, b : 1, c : 1, d : 2, e : 3;
    S();
};

S::S() : a(0), b(0), c(1), d(0), e(6) {}

to this:

void %_ZN1SC1Ev(%struct.S* %this) {
entry:
        %tmp.1 = getelementptr %struct.S* %this, int 0, uint 0
        store ubyte 38, ubyte* %tmp.1
        ret void
}

much earlier (in gccas instead of only in gccld after DSE runs).


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@26050 91177308-0d34-0410-b5e6-96231b3b80d8
 2006-02-08 03:25:32 +00:00
Chris Lattner
fe243ebb64 Implement some more interesting select sccp cases. This implements: 
test/Regression/Transforms/SCCP/select.ll


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@26049 91177308-0d34-0410-b5e6-96231b3b80d8
 2006-02-08 02:38:11 +00:00
Chris Lattner
62d1ade893 Fix a problem in my patch yesterday, causing a miscompilation of 176.gcc 
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@26045 91177308-0d34-0410-b5e6-96231b3b80d8
 2006-02-08 01:20:23 +00:00
Chris Lattner
d89d888cc5 Fix Transforms/InstCombine/2006-02-07-SextZextCrash.ll 
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@26040 91177308-0d34-0410-b5e6-96231b3b80d8
 2006-02-07 19:07:40 +00:00
Chris Lattner
74c51a0ff2 Generalize MaskedValueIsZero into a ComputeMaskedNonZeroBits function, which 
is just as efficient as MVIZ and is also more general.

Fix a few minor bugs introduced in recent patches


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@26036 91177308-0d34-0410-b5e6-96231b3b80d8
 2006-02-07 08:05:22 +00:00
Chris Lattner
3bedbd9d71 Make MaskedValueIsZero take a uint64_t instead of a ConstantIntegral as a 
mask.  This allows the code to be simpler and more efficient.

Also, generalize some of the cases in MVIZ a bit, making it slightly more aggressive.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@26035 91177308-0d34-0410-b5e6-96231b3b80d8
 2006-02-07 07:27:52 +00:00
Chris Lattner
1a074fce15 Use Type::getIntegralTypeMask() to simplify some code 
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@26034 91177308-0d34-0410-b5e6-96231b3b80d8
 2006-02-07 07:00:41 +00:00
Chris Lattner
6dce1a7dfe Implement the beginnings of a facility for simplifying expressions based on 
'demanded bits', inspired by Nate's work in the dag combiner.  This isn't
complete, but needs to unrelated instcombiner changes to continue.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@26033 91177308-0d34-0410-b5e6-96231b3b80d8
 2006-02-07 06:56:34 +00:00
Chris Lattner
5f3b0eeddb Turn A % (C << N), where C is 2^k, into A & ((C << N)-1) [urem only]. 
Turn A / (C1 << N), where C1 is "1<<C2" into A >> (N+C2) [udiv only].

Tested with: rem.ll:test5, div.ll:test10


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@26003 91177308-0d34-0410-b5e6-96231b3b80d8
 2006-02-05 07:54:04 +00:00
Chris Lattner
0a70f219f4 Use SCEVExpander::InsertCastOfTo instead of our own code. This reduces 
#LLVM LOC, and auto-cse's cast instructions.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@25974 91177308-0d34-0410-b5e6-96231b3b80d8
 2006-02-04 09:52:43 +00:00
Chris Lattner
221fc3c6d6 Fix two significant bugs in LSR: 
1. When rewriting code in outer loops, sometimes we would insert code into
   inner loops that is invariant in that loop.
2. Notice that 4*(2+x) is 8+4*x and use that to simplify expressions.

This is a performance neutral change.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@25964 91177308-0d34-0410-b5e6-96231b3b80d8
 2006-02-04 07:36:50 +00:00
Jeff Cohen
9471c8a93b Improve compatibility with VC2005, patch by Morten Ofstad! 
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@25661 91177308-0d34-0410-b5e6-96231b3b80d8
 2006-01-26 20:41:32 +00:00
Chris Lattner
15256cb14e Fix Regression/Transforms/ScalarRepl/2006-01-24-IllegalUnionPromoteCrash.ll 
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@25587 91177308-0d34-0410-b5e6-96231b3b80d8
 2006-01-24 19:36:27 +00:00
Chris Lattner
dac58ad983 Make iostream #inclusion explicit 
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@25514 91177308-0d34-0410-b5e6-96231b3b80d8
 2006-01-22 23:32:06 +00:00
Chris Lattner
bc528efa76 Implement casts.ll:test26: a cast from float -> double -> integer, doesn't 
need the float->double part.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@25452 91177308-0d34-0410-b5e6-96231b3b80d8
 2006-01-19 07:40:22 +00:00
Robert Bocchino
8fcf01ead0 Lowerpacked and SCCP support for the insertelement operation. 
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@25406 91177308-0d34-0410-b5e6-96231b3b80d8
 2006-01-17 20:06:55 +00:00
Chris Lattner
72223eea95 fix a crash due to missing parens 
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@25363 91177308-0d34-0410-b5e6-96231b3b80d8
 2006-01-16 19:47:21 +00:00
Chris Lattner
57a47d6a4b This pass has never worked correctly. Remove. 
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@25349 91177308-0d34-0410-b5e6-96231b3b80d8
 2006-01-16 01:06:00 +00:00
Chris Lattner
516a74c01a FunctionPass's cannot do IPO things. 
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@25315 91177308-0d34-0410-b5e6-96231b3b80d8
 2006-01-14 19:30:35 +00:00
Robert Bocchino
1d7456d0bf Added instcombine support for extractelement. 
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@25299 91177308-0d34-0410-b5e6-96231b3b80d8
 2006-01-13 22:48:06 +00:00
Chris Lattner
a728ddc815 Do a simple instcombine xforms to delete llvm.stackrestore cases. 
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@25294 91177308-0d34-0410-b5e6-96231b3b80d8
 2006-01-13 21:28:09 +00:00
Chris Lattner
8b0ea313d9 Simplify this a tiny bit by using the new IntrinsicInst functionality. 
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@25292 91177308-0d34-0410-b5e6-96231b3b80d8
 2006-01-13 20:11:04 +00:00
Chris Lattner
88cac3d2f7 Switch these to using ETForest instead of DominatorSet to compute itself. 
Patch written by Daniel Berlin!


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@25202 91177308-0d34-0410-b5e6-96231b3b80d8
 2006-01-11 05:10:20 +00:00
Chris Lattner
19ef3d5be2 Switch this to using ETForest instead of DominatorSet to compute itself. 
Patch written by Daniel Berlin!


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@25201 91177308-0d34-0410-b5e6-96231b3b80d8
 2006-01-11 05:09:40 +00:00
Robert Bocchino
56107e21a5 Added lower packed support for the extractelement operation. 
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@25180 91177308-0d34-0410-b5e6-96231b3b80d8
 2006-01-10 19:05:05 +00:00
Chris Lattner
e8d56c536d fix some 176.gcc miscompilation from my previous patch. 
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@25137 91177308-0d34-0410-b5e6-96231b3b80d8
 2006-01-07 01:32:28 +00:00
Chris Lattner
4f637d4db1 silence some bogus gcc warnings on fenris 
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@25130 91177308-0d34-0410-b5e6-96231b3b80d8
 2006-01-06 17:59:59 +00:00
Chris Lattner
ad0124c188 Enhance the shift-shift folding code to allow a no-op cast to occur in between 
the shifts.

This allows us to fold this (which is the 'integer add a constant' sequence
from cozmic's scheme compmiler):

int %x(uint %anf-temporary776) {
        %anf-temporary777 = shr uint %anf-temporary776, ubyte 1
        %anf-temporary800 = cast uint %anf-temporary777 to int
        %anf-temporary804 = shl int %anf-temporary800, ubyte 1
        %anf-temporary805 = add int %anf-temporary804, -2
        %anf-temporary806 = or int %anf-temporary805, 1
        ret int %anf-temporary806
}

into this:

int %x(uint %anf-temporary776) {
        %anf-temporary776 = cast uint %anf-temporary776 to int
        %anf-temporary776.mask1 = add int %anf-temporary776, -2
        %anf-temporary805 = or int %anf-temporary776.mask1, 1
        ret int %anf-temporary805
}

note that instcombine already knew how to eliminate the AND that the two
shifts fold into.  This is tested by InstCombine/shift.ll:test26

-Chris


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@25128 91177308-0d34-0410-b5e6-96231b3b80d8
 2006-01-06 07:52:12 +00:00
Chris Lattner
830ed03e8b Simplify the code a bit more 
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@25126 91177308-0d34-0410-b5e6-96231b3b80d8
 2006-01-06 07:22:22 +00:00
Chris Lattner
4d5542ce6e Extract a bunch of code out of visitShiftInst into FoldShiftByConstant. No 
functionality changes.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@25125 91177308-0d34-0410-b5e6-96231b3b80d8
 2006-01-06 07:12:35 +00:00
Duraid Madina
b5186853f8 getting there... 
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@25021 91177308-0d34-0410-b5e6-96231b3b80d8
 2005-12-26 13:48:44 +00:00