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Author SHA1 Message Date
Nick Lewycky
42445be0df Firstly, having a BranchInst isn't exclusive with having an unwind_to. 
Secondly, we have to check whether the branch is actually pointing to the block
with the unwind in it. We could have gotten here because of the unwind_to alone.

llvm-svn: 48099
 2008-03-09 07:50:37 +00:00
Nick Lewycky
f3d637fa14 A BB that unwind_to an "unwind" inst is that same as one that doesn't unwind_to 
at all.

llvm-svn: 48096
 2008-03-09 07:36:38 +00:00
Nick Lewycky
5ce9b521d7 Update the inliner and simplifycfg to handle unwind_to. 
llvm-svn: 48086
 2008-03-09 05:10:13 +00:00
Anton Korobeynikov
1bfd121321 Make Transforms to be 4.3 warnings-clean 
llvm-svn: 47371
 2008-02-20 11:26:25 +00:00
Chris Lattner
6b39cb907b switch simplifycfg from using vectors for most things to smallvectors, 
this speeds it up 2.3% on eon.

llvm-svn: 47261
 2008-02-18 07:42:56 +00:00
Chris Lattner
f391883670 don't hoist FP additions into unconditional adds + selects. This 
could theoretically introduce a trap, but is also a performance issue.
This speeds up ptrdist/ks by 8%.

llvm-svn: 45533
 2008-01-03 07:25:26 +00:00
Chris Lattner
f3ebc3f3d2 Remove attribution from file headers, per discussion on llvmdev. 
llvm-svn: 45418
 2007-12-29 20:36:04 +00:00
Devang Patel
7a2c66b11e If succ has succ itself as one of the predecessors then do 
not merge current bb and succ even if bb's terminator is
unconditional branch to succ.

llvm-svn: 45305
 2007-12-22 01:32:53 +00:00
Duncan Sands
ad0ea2d430 Fix PR1146: parameter attributes are longer part of 
the function type, instead they belong to functions
and function calls.  This is an updated and slightly
corrected version of Reid Spencer's original patch.
The only known problem is that auto-upgrading of
bitcode files doesn't seem to work properly (see
test/Bitcode/AutoUpgradeIntrinsics.ll).  Hopefully
a bitcode guru (who might that be? :) ) will fix it.

llvm-svn: 44359
 2007-11-27 13:23:08 +00:00
David Greene
17a5dfe6f7 New CallInst interface to address GLIBCXX_DEBUG errors caused by 
indexing an empty std::vector.

Updates to all clients.

llvm-svn: 40660
 2007-08-01 03:43:44 +00:00
Dan Gohman
30978078bf Minor comment cleanups. 
llvm-svn: 37321
 2007-05-24 14:36:04 +00:00
Chris Lattner
77a3edcb92 remove use of Instruction::getNext 
llvm-svn: 36199
 2007-04-17 17:47:54 +00:00
Chris Lattner
b7b75145f1 reduce use of std::set 
llvm-svn: 35576
 2007-04-02 01:44:59 +00:00
Dan Gohman
dcb291faa4 Change uses of Function::front to Function::getEntryBlock for readability. 
llvm-svn: 35265
 2007-03-22 16:38:57 +00:00
Reid Spencer
bb38d79ad6 Make sorting of ConstantInt be APInt clean through use of ult function. 
llvm-svn: 34853
 2007-03-02 23:01:14 +00:00
Chris Lattner
a06a8fd2d7 Eliminate use of ctors that take vectors. 
llvm-svn: 34219
 2007-02-13 02:10:56 +00:00
Chris Lattner
8dd4cae4f8 simplify code by using Value::takeName 
llvm-svn: 34177
 2007-02-11 01:37:51 +00:00
Chris Lattner
024f4ab383 Adjust #includes to match movement of constant folding code from transformutils to libanalysis. 
llvm-svn: 33680
 2007-01-30 23:46:24 +00:00
Reid Spencer
a94d394ad2 For PR1043: 
This is the final patch for this PR. It implements some minor cleanup
in the use of IntegerType, to wit:
1. Type::getIntegerTypeMask -> IntegerType::getBitMask
2. Type::Int*Ty changed to IntegerType* from Type*
3. ConstantInt::getType() returns IntegerType* now, not Type*

This also fixes PR1120.

Patch by Sheng Zhou.

llvm-svn: 33370
 2007-01-19 21:13:56 +00:00
Chris Lattner
03c4953cdd rename Type::isIntegral to Type::isInteger, eliminating the old Type::isInteger. 
rename Type::getIntegralTypeMask to Type::getIntegerTypeMask.

This makes naming much more consistent.  For example, there are now no longer any
instances of IntegerType that are not considered isInteger! :)

llvm-svn: 33225
 2007-01-15 02:27:26 +00:00
Chris Lattner
1942249c5b Eliminate calls to isInteger, generalizing code and tightening checks as needed. 
llvm-svn: 33218
 2007-01-15 01:55:30 +00:00
Reid Spencer
cddc9dfe97 Implement review feedback for the ConstantBool->ConstantInt merge. Chris 
recommended that getBoolValue be replaced with getZExtValue and that
get(bool) be replaced by get(const Type*, uint64_t). This implements
those changes.

llvm-svn: 33110
 2007-01-12 04:24:46 +00:00
Reid Spencer
542964f55b Rename BoolTy as Int1Ty. Patch by Sheng Zhou. 
llvm-svn: 33076
 2007-01-11 18:21:29 +00:00
Zhou Sheng
75b871fb1e For PR1043: 
Merge ConstantIntegral and ConstantBool into ConstantInt.
Remove ConstantIntegral and ConstantBool from LLVM.

llvm-svn: 33073
 2007-01-11 12:24:14 +00:00
Reid Spencer
266e42b312 For PR950: 
This patch removes the SetCC instructions and replaces them with the ICmp
and FCmp instructions. The SetCondInst instruction has been removed and
been replaced with ICmpInst and FCmpInst.

llvm-svn: 32751
 2006-12-23 06:05:41 +00:00
Reid Spencer
6c38f0bb07 For PR950: 
The long awaited CAST patch. This introduces 12 new instructions into LLVM
to replace the cast instruction. Corresponding changes throughout LLVM are
provided. This passes llvm-test, llvm/test, and SPEC CPUINT2000 with the
exception of 175.vpr which fails only on a slight floating point output
difference.

llvm-svn: 31931
 2006-11-27 01:05:10 +00:00
Bill Wendling
4ae401074c Remove #include <iostream> and use llvm_* streams instead. 
llvm-svn: 31925
 2006-11-26 10:17:54 +00:00
Chris Lattner
95adf8f1da Do not convert massive blocks on phi nodes into select statements. Instead 
only do these transformations if there are a small number of phi's.
This speeds up Ptrdist/ks from 2.35s to 2.19s on my mac pro.

llvm-svn: 31853
 2006-11-18 19:19:36 +00:00
Reid Spencer
fdff938a7e For PR950: 
This patch converts the old SHR instruction into two instructions,
AShr (Arithmetic) and LShr (Logical). The Shr instructions now are not
dependent on the sign of their operands.

llvm-svn: 31542
 2006-11-08 06:47:33 +00:00
Reid Spencer
de46e48420 For PR786: 
Turn on -Wunused and -Wno-unused-parameter. Clean up most of the resulting
fall out by removing unused variables. Remaining warnings have to do with
unused functions (I didn't want to delete code without review) and unused
variables in generated code. Maintainers should clean up the remaining
issues when they see them. All changes pass DejaGnu tests and Olden.

llvm-svn: 31380
 2006-11-02 20:25:50 +00:00
Chris Lattner
fc519cd2d1 Fix SimplifyCFG/2006-10-29-InvokeCrash.ll, a crash compiling QT. 
llvm-svn: 31284
 2006-10-29 21:21:20 +00:00
Reid Spencer
e0fc4dfc22 For PR950: 
This patch implements the first increment for the Signless Types feature.
All changes pertain to removing the ConstantSInt and ConstantUInt classes
in favor of just using ConstantInt.

llvm-svn: 31063
 2006-10-20 07:07:24 +00:00
Chris Lattner
b8b11599dd Fix SimplifyCFG/2006-10-19-UncondDiv.ll by disabling a bad xform. 
llvm-svn: 31061
 2006-10-20 00:42:07 +00:00
Chris Lattner
c9009d917d 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
b5c9d7a0af Fix an infinite loop on Transforms/SimplifyCFG/2006-06-12-InfLoop.ll 
llvm-svn: 28758
 2006-06-12 20:18:01 +00:00
Chris Lattner
35515557c7 remove some dead code identified by coverity 
llvm-svn: 28289
 2006-05-14 18:45:44 +00:00
Chris Lattner
3237da073e remove dead variables 
llvm-svn: 28286
 2006-05-14 18:33:57 +00:00
Chris Lattner
d95665188b Fix Transforms/SimplifyCFG/2006-02-17-InfiniteUnroll.ll 
llvm-svn: 26275
 2006-02-18 00:33:17 +00:00
Chris Lattner
469640e506 Add explicit #includes of <iostream> 
llvm-svn: 25509
 2006-01-22 22:53:01 +00:00
Chris Lattner
2820b8c855 Fix SimplifyCFG/2005-12-03-IncorrectPHIFold.ll 
llvm-svn: 24581
 2005-12-03 18:25:58 +00:00
Chris Lattner
4c3b2b536c Clean up the code a bit. Use isInstructionTriviallyDead to be more aggressive 
and more correct than use_empty().  This fixes PR635 and
SimplifyCFG/2005-10-02-InvokeSimplify.ll

llvm-svn: 23616
 2005-10-03 23:43:43 +00:00
Chris Lattner
499e33646e remove some debugging code 
llvm-svn: 23411
 2005-09-23 18:49:09 +00:00
Chris Lattner
c59a371d45 Fold two consequtive branches that share a common destination between them. 
This implements SimplifyCFG/branch-fold.ll, and is useful on ?:/min/max heavy
code

llvm-svn: 23410
 2005-09-23 18:47:20 +00:00
Chris Lattner
3a978bf66d simplify some logic further 
llvm-svn: 23408
 2005-09-23 07:23:18 +00:00
Chris Lattner
cc14ebc17b pull a bunch of logic out of SimplifyCFG into a helper fn 
llvm-svn: 23407
 2005-09-23 06:39:30 +00:00
Chris Lattner
6c70106053 Start threading across blocks with code in them, so long as the code does 
not define a value that is used outside of it's block.  This catches many
more simplifications, e.g. 854 in 176.gcc, 137 in vpr, etc.

This implements branch-phi-thread.ll:test3.ll

llvm-svn: 23397
 2005-09-20 01:48:40 +00:00
Chris Lattner
f0bd8d0107 Implement merging of blocks with the same condition if the block has multiple 
predecessors.  This implements branch-phi-thread.ll::test1

llvm-svn: 23395
 2005-09-20 00:43:16 +00:00
Chris Lattner
049cb4482f Reject a case we don't handle yet 
llvm-svn: 23393
 2005-09-19 23:57:04 +00:00
Chris Lattner
a160924d57 remove debugging code :-/ 
llvm-svn: 23392
 2005-09-19 23:50:15 +00:00
Chris Lattner
748f903046 Implement SimplifyCFG/branch-phi-thread.ll, the most trivial case of threading 
control across branches with determined outcomes.  More generality to follow.
This triggers a couple thousand times in specint.

llvm-svn: 23391
 2005-09-19 23:49:37 +00:00
Chris Lattner
d683bdd0f8 Fix Transforms/SimplifyCFG/2005-08-03-PHIFactorCrash.ll, a problem that 
occurred while bugpointing another testcase

llvm-svn: 22621
 2005-08-03 17:59:45 +00:00
Chris Lattner
2dbf1960ff Finally, add the required constraint checks to fix Transforms/SimplifyCFG/2005-08-01-PHIUpdateFail.ll 
the right way

llvm-svn: 22615
 2005-08-03 00:59:12 +00:00
Chris Lattner
908036942c Simplify some code, add the correct pred checks 
llvm-svn: 22613
 2005-08-03 00:38:27 +00:00
Chris Lattner
982b75c061 Refactor code out of PropagatePredecessorsForPHIs, turning it into a pure function with no side-effects 
llvm-svn: 22612
 2005-08-03 00:29:26 +00:00
Chris Lattner
1f047fd513 use splice instead of remove/insert to avoid some symtab operations 
llvm-svn: 22611
 2005-08-03 00:23:42 +00:00
Chris Lattner
76dc204488 move two functions up in the file, use SafeToMergeTerminators to eliminate 
some duplicated code

llvm-svn: 22610
 2005-08-03 00:19:45 +00:00
Chris Lattner
733d6704ce Rip some code out of the main SimplifyCFG function into a subfunction and 
call it from the only place it is live.  No functionality changes.

llvm-svn: 22609
 2005-08-03 00:11:16 +00:00
Chris Lattner
ac594de8dc Disable this patch: 
http://lists.cs.uiuc.edu/pipermail/llvm-commits/Week-of-Mon-20050801/027345.html

This breaks real programs and only fixes an obscure regression testcase.  A
real fix is in development.

llvm-svn: 22606
 2005-08-02 23:31:38 +00:00
Chris Lattner
eee90f7eb4 Change a place to use an arbitrary value instead of null, when possible 
llvm-svn: 22605
 2005-08-02 23:29:23 +00:00
Chris Lattner
4fd3e16cbd This code was very close, but not quite right. It did not take into 
consideration the case where a reference in an unreachable block could
occur.  This fixes Transforms/SimplifyCFG/2005-08-01-PHIUpdateFail.ll,
something I ran into while bugpoint'ing another pass.

llvm-svn: 22584
 2005-08-02 03:24:05 +00:00
Chris Lattner
5e735294bf Don't crash on: X = phi (X, X). 
This fixes PR584 and Transforms/SimplifyCFG/2005-06-16-PHICrash.ll

llvm-svn: 22232
 2005-06-17 01:45:53 +00:00
Chris Lattner
19f9f32a5c Fix Transforms/SimplifyCFG/switch-simplify-crash.ll 
llvm-svn: 22158
 2005-05-20 22:19:54 +00:00
Chris Lattner
bcefcf8552 Make sure to preserve the calling convention when changing an invoke into 
a call.  This fixes Prolangs-C++/deriv2, kimwitu++, and Misc-C++/bigfib
on X86 with -enable-x86-fastcc.

llvm-svn: 22023
 2005-05-14 12:21:56 +00:00
Misha Brukman
b1c9317bb4 Remove trailing whitespace 
llvm-svn: 21427
 2005-04-21 23:48:37 +00:00
Chris Lattner
b38b443b15 Teach simplifycfg that setcc is cheap and non-trapping, so that it can 
convert this:

        %tmp.1 = seteq int %i, 0                ; <bool> [#uses=1]
        br bool %tmp.1, label %shortcirc_done, label %shortcirc_next

shortcirc_next:         ; preds = %entry
        %tmp.4 = seteq int %j, 0                ; <bool> [#uses=1]
        br label %shortcirc_done

shortcirc_done:         ; preds = %shortcirc_next, %entry
        %shortcirc_val = phi bool [ %tmp.4, %shortcirc_next ], [ true, %entry ]         ; <bool> [#uses=1]

to this:
        %tmp.1 = seteq int %i, 0                ; <bool> [#uses=1]
        %tmp.4 = seteq int %j, 0                ; <bool> [#uses=1]
        %shortcirc_val = select bool %tmp.1, bool true, bool %tmp.4             ; <bool> [#uses=1]

... which is later simplified by instcombine into an or.

llvm-svn: 21388
 2005-04-21 05:31:13 +00:00
Chris Lattner
95f16a3ac4 Get rid of this for_each loop 
llvm-svn: 21253
 2005-04-12 18:51:33 +00:00
Chris Lattner
0ce80cd542 Fix spelling, patch contributed by Gabor Greif! 
llvm-svn: 20343
 2005-02-27 06:18:25 +00:00
Chris Lattner
cc6d75fddf remove extraneous cast 
llvm-svn: 20334
 2005-02-26 18:33:28 +00:00
Chris Lattner
1cca959e5d Implement Transforms/SimplifyCFG/switch_thread.ll 
This does a simple form of "jump threading", which eliminates CFG edges that
are provably dead.  This triggers 90 times in the external tests, and
eliminating CFG edges is always always a good thing! :)

llvm-svn: 20300
 2005-02-24 06:17:52 +00:00
Chris Lattner
a35dfcedd3 switchinst ctor now takes a hint for the number of cases that it will have. 
llvm-svn: 19898
 2005-01-29 00:38:26 +00:00
Chris Lattner
3215bb6049 Implement SimplifyCFG/DeadSetCC.ll 
SimplifyCFG is one of those passes that we use for final cleanup: it should
not rely on other passes to clean up its garbage.  This fixes the "why are
trivially dead setcc's in the output of gccas" problem.

llvm-svn: 19212
 2005-01-01 16:02:12 +00:00
Chris Lattner
4fc998da2e Fix Regression/Transforms/SimplifyCFG/2004-12-10-SimplifyCFGCrash.ll, 
and the failure on make_dparser last night.

llvm-svn: 18766
 2004-12-10 17:42:31 +00:00
Chris Lattner
019445715e Squelch warning 
llvm-svn: 18381
 2004-11-30 07:47:34 +00:00
Chris Lattner
fd8cbc257e Alkis noticed that this variable is dead. Thanks! 
llvm-svn: 18369
 2004-11-30 04:01:44 +00:00
Chris Lattner
389cfac0d1 If we have something like this: 
if (x) {
    code
    ...
  } else {
    code
    ...
  }

Turn it into:

  code
  if (x) {
    ...
  } else {
    ...
  }

This reduces code size and in some common cases allows us to completely
eliminate the conditional.  This turns several if/then/else blocks in loops
into straightline code in 179.art, turning the loops into single basic blocks
(good for modsched even!).

Maybe now brg will leave me alone ;-)

llvm-svn: 18366
 2004-11-30 00:29:14 +00:00
Chris Lattner
93d1e39f3e Do not compute the predecessor list for a block unless we need it. 
This speeds up simplifycfg on this program, from 44.87s to 0.29s (with
a profiled build):

 #define CL0(a) case a: goto c;
 #define CL1(a) CL0(a##0) CL0(a##1) CL0(a##2) CL0(a##3) CL0(a##4) CL0(a##5) \
 CL0(a##6) CL0(a##7) CL0(a##8) CL0(a##9)
 #define CL2(a) CL1(a##0) CL1(a##1) CL1(a##2) CL1(a##3) CL1(a##4) CL1(a##5) \
 CL1(a##6) CL1(a##7) CL1(a##8) CL1(a##9)
 #define CL3(a) CL2(a##0) CL2(a##1) CL2(a##2) CL2(a##3) CL2(a##4) CL2(a##5) \
 CL2(a##6) CL2(a##7) CL2(a##8) CL2(a##9)
 #define CL4(a) CL3(a##0) CL3(a##1) CL3(a##2) CL3(a##3) CL3(a##4) CL3(a##5) \
 CL3(a##6) CL3(a##7) CL3(a##8) CL3(a##9)

 void f();

 void a() {
     int b;
  c: switch (b) {
         CL4(1)
     }
 }

This testcase is contrived to expose N^2 behavior, but this patch should speedup
simplifycfg on any programs that use large switch statements.  This testcase
comes from GCC PR17895.

llvm-svn: 17389
 2004-11-01 06:53:58 +00:00
Reid Spencer
fad217c847 Eliminate compilation warning on uninitialized variable. 
llvm-svn: 17163
 2004-10-22 16:10:39 +00:00
Chris Lattner
5edb2f32d0 Simplify code by deleting instructions that preceed unreachable instructions. 
Simplify code by simplifying terminators that branch to blocks that start
with an unreachable instruction.

llvm-svn: 17116
 2004-10-18 04:07:22 +00:00
Chris Lattner
45c35b1d1f When converting phi nodes into select instructions, we shouldn't promote PHI 
nodes unless we KNOW that we are able to promote all of them.

This fixes: test/Regression/Transforms/SimplifyCFG/PhiNoEliminate.ll

llvm-svn: 16973
 2004-10-14 05:13:36 +00:00
Chris Lattner
879ce7894c Do not insert trivially dead select instructions, which allows us to 
potentially fold more in one pass.

llvm-svn: 16583
 2004-09-29 05:43:32 +00:00
Reid Spencer
6614946443 Convert code to compile with vc7.1. 
Patch contributed by Paolo Invernizzi. Thanks Paolo!

llvm-svn: 16368
 2004-09-15 17:06:42 +00:00
Alkis Evlogimenos
a5c04ee50f Fixes to make LLVM compile with vc7.1. 
Patch contributed by Paolo Invernizzi!

llvm-svn: 16152
 2004-09-03 18:19:51 +00:00
Reid Spencer
7c16caa336 Changes For Bug 352 
Move include/Config and include/Support into include/llvm/Config,
include/llvm/ADT and include/llvm/Support. From here on out, all LLVM
public header files must be under include/llvm/.

llvm-svn: 16137
 2004-09-01 22:55:40 +00:00
Brian Gaeke
902dcf0729 These files don't need to include <iostream> since they include "Support/Debug.h". 
llvm-svn: 15089
 2004-07-21 20:50:33 +00:00
Chris Lattner
5823ac1c21 Implement SimplifyCFG/BrUnwind.ll 
llvm-svn: 15022
 2004-07-20 01:17:38 +00:00
Reid Spencer
ef784f01dd bug 122: 
- Minimize redundant isa<GlobalValue> usage

llvm-svn: 14948
 2004-07-18 00:32:14 +00:00
Chris Lattner
32c518e526 Progress on PR341 
llvm-svn: 14840
 2004-07-15 02:06:12 +00:00
Reid Spencer
eb04d9bcb4 Add #include <iostream> since Value.h does not #include it any more. 
llvm-svn: 14622
 2004-07-04 12:19:56 +00:00
Chris Lattner
f12c4a3d37 *FINALLY* Fix a really nasty nondeterministic bug that has been haunting us 
since May 1st.  In this code, the pred iterator was being invalidated sometimes
causing the wrong entries to be added to PHI nodes.

The fix for this is to defererence and safe the *PI value before we hack on
branch instructions, which changes use/def chains, which SOMETIMES invalidates
the iterator.

llvm-svn: 14278
 2004-06-21 07:19:01 +00:00
Chris Lattner
9734fd0980 Add some DEBUG output to the simplifycfg routines 
Fix another non-deterministic behavior, this one should actually speed up the
code though as it was doing silly things.

llvm-svn: 14258
 2004-06-20 01:13:18 +00:00
Chris Lattner
b2b151d297 Do not sort by the address of LLVM ConstantInt* objects. This produces 
nondeterministic results that depend on where these objects land in memory.
Instead, sort by the value of the constant, which is stable.

Before this patch, the -simplifycfg pass run from two different compilers
could cause different code to be generated, though it was semantically the
same:

@@ -12258,8 +12258,8 @@
        %s_addr.1 = phi sbyte* [ %s, %entry ], [ %inc.0, %no_exit ]             ; <sbyte*> [#uses=5]
        %tmp.1 = load sbyte* %s_addr.1          ; <sbyte> [#uses=1]
        switch sbyte %tmp.1, label %no_exit [
-                sbyte 0, label %loopexit
                 sbyte 46, label %loopexit
+                sbyte 0, label %loopexit
        ]

We need to stomp all of this stuff out.

llvm-svn: 14243
 2004-06-19 07:02:14 +00:00
Chris Lattner
be6f06818c Do not clone arbitrary condition instructions. 
llvm-svn: 13316
 2004-05-02 05:19:36 +00:00
Chris Lattner
51a6dbcb65 Do not infinitely "unroll" single BB loops. 
llvm-svn: 13315
 2004-05-02 05:02:03 +00:00
Chris Lattner
1e94ed606e Dont' merge terminators that are needed to select PHI node values. 
llvm-svn: 13312
 2004-05-02 01:00:44 +00:00
Chris Lattner
2e93c4275e Implement SimplifyCFG/branch-cond-merge.ll 
Turning "if (A < B && B < C)" into "if (A < B & B < C)"

llvm-svn: 13311
 2004-05-01 23:35:43 +00:00
Chris Lattner
4cbd160b45 Fix my missing parens 
llvm-svn: 13307
 2004-05-01 22:41:51 +00:00
Chris Lattner
88da6f7b52 Implement SimplifyCFG/branch-cond-prop.ll 
llvm-svn: 13306
 2004-05-01 22:36:37 +00:00
Chris Lattner
0aa565647c Fold code like: 
if (C)
    V1 |= V2;

into:
  Vx = V1 | V2;
  V1 = select C, V1, Vx

when the expression can be evaluated unconditionally and is *cheap* to
execute.  This limited form of if conversion is quite handy in lots of cases.
For example, it turns this testcase into straight-line code:

int in0 ; int in1 ; int in2 ; int in3 ;
int in4 ; int in5 ; int in6 ; int in7 ;
int in8 ; int in9 ; int in10; int in11;
int in12; int in13; int in14; int in15;
long output;

void mux(void) {
  output =
      (in0   ?  0x00000001 : 0) | (in1   ?  0x00000002 : 0) |
      (in2   ?  0x00000004 : 0) | (in3   ?  0x00000008 : 0) |
      (in4   ?  0x00000010 : 0) | (in5   ?  0x00000020 : 0) |
      (in6   ?  0x00000040 : 0) | (in7   ?  0x00000080 : 0) |
      (in8   ?  0x00000100 : 0) | (in9   ?  0x00000200 : 0) |
      (in10  ?  0x00000400 : 0) | (in11  ?  0x00000800 : 0) |
      (in12  ?  0x00001000 : 0) | (in13  ?  0x00002000 : 0) |
      (in14  ?  0x00004000 : 0) | (in15  ?  0x00008000 : 0) ;
}

llvm-svn: 12798
 2004-04-09 22:50:22 +00:00
Chris Lattner
eed034bcd3 Fix the obvious bug in my previous checkin 
llvm-svn: 12618
 2004-04-02 18:15:10 +00:00
Chris Lattner
9f0db32625 Implement Transforms/SimplifyCFG/return-merge.ll 
This actually causes us to turn code like:

  return C ? A : B;

into a select instruction.

llvm-svn: 12617
 2004-04-02 18:13:43 +00:00