105 Commits

Author SHA1 Message Date
Chris Lattner
cdb67482da 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
da1f5b882a 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
4bafa71dc1 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
cc8731fef4 Fix SimplifyCFG/2006-10-29-InvokeCrash.ll, a crash compiling QT.
llvm-svn: 31284
2006-10-29 21:21:20 +00:00
Reid Spencer
d414793dbc 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
d9aa90ded4 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
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
649af38df3 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
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
Chris Lattner
d9b0de3240 Fix Transforms/SimplifyCFG/2006-02-17-InfiniteUnroll.ll
llvm-svn: 26275
2006-02-18 00:33:17 +00:00
Chris Lattner
adff158fbd Add explicit #includes of <iostream>
llvm-svn: 25509
2006-01-22 22:53:01 +00:00
Chris Lattner
f9a1c37c84 Fix SimplifyCFG/2005-12-03-IncorrectPHIFold.ll
llvm-svn: 24581
2005-12-03 18:25:58 +00:00
Chris Lattner
cd43592209 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
5ce68bab6c remove some debugging code
llvm-svn: 23411
2005-09-23 18:49:09 +00:00
Chris Lattner
88c234b5e4 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
67437dce2c simplify some logic further
llvm-svn: 23408
2005-09-23 07:23:18 +00:00
Chris Lattner
48df043325 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
07cf4f249d 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
44a9487815 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
4013184d6b Reject a case we don't handle yet
llvm-svn: 23393
2005-09-19 23:57:04 +00:00
Chris Lattner
642f0d6aea remove debugging code :-/
llvm-svn: 23392
2005-09-19 23:50:15 +00:00
Chris Lattner
34785e2d43 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
3672ceb70b 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
6e1d5a8b28 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
cbf4b650ba Simplify some code, add the correct pred checks
llvm-svn: 22613
2005-08-03 00:38:27 +00:00
Chris Lattner
c59014baef 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
0f4e0d19cc use splice instead of remove/insert to avoid some symtab operations
llvm-svn: 22611
2005-08-03 00:23:42 +00:00
Chris Lattner
adbd086f50 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
b9efb90e1a 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
df31d75597 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
b5906d5783 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
b8fd6a098e 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
8c76d5c957 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
b13335fff2 Fix Transforms/SimplifyCFG/switch-simplify-crash.ll
llvm-svn: 22158
2005-05-20 22:19:54 +00:00
Chris Lattner
214f1a8cf9 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
53e199440e Remove trailing whitespace
llvm-svn: 21427
2005-04-21 23:48:37 +00:00
Chris Lattner
6ce1b109aa 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
ee06161a63 Get rid of this for_each loop
llvm-svn: 21253
2005-04-12 18:51:33 +00:00
Chris Lattner
a024984017 Fix spelling, patch contributed by Gabor Greif!
llvm-svn: 20343
2005-02-27 06:18:25 +00:00
Chris Lattner
14f720d625 remove extraneous cast
llvm-svn: 20334
2005-02-26 18:33:28 +00:00
Chris Lattner
7a434679c3 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
ccc0c99fae 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
5fff877f74 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
40e97884f6 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
c58bc8d96e Squelch warning
llvm-svn: 18381
2004-11-30 07:47:34 +00:00
Chris Lattner
25b93fea2a Alkis noticed that this variable is dead. Thanks!
llvm-svn: 18369
2004-11-30 04:01:44 +00:00
Chris Lattner
b237a19a78 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
3083f2a424 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
9f6f128630 Eliminate compilation warning on uninitialized variable.
llvm-svn: 17163
2004-10-22 16:10:39 +00:00