88 Commits

Author SHA1 Message Date
Owen Anderson
bea70ee1de Hopefully the final attempt at making IndVars preserve LCSSA.
This should fix PR 831.

llvm-svn: 29141
2006-07-14 18:49:15 +00:00
Chris Lattner
9b6c02ebe4 Revert this patch temporarily until PR831 is fixed.
llvm-svn: 29134
2006-07-13 19:05:20 +00:00
Owen Anderson
dea9202e3b IndVars now (correctly) preserves LCSSA form.
llvm-svn: 29126
2006-07-12 21:29:14 +00:00
Owen Anderson
15b1f7d2cd Revert my indvars changes because they were breaking things. Unfortunately this
didn't start showing up until after the recent instcombine fixes.

llvm-svn: 29102
2006-07-11 07:25:33 +00:00
Owen Anderson
b659bb4196 De-pessimize the handling of LCSSA Phi nodes in IndVarSimplify. Hopefully this
will make Shootout-C/nestedloop faster.

llvm-svn: 28924
2006-06-27 02:17:08 +00:00
Chris Lattner
053fb9319d Fix IndVarsSimplify/2006-06-16-Indvar-LCSSA-Crash.ll, a case where a
"LCSSA" phi node causes indvars to break dominance properties.  This fixes
causes indvars to avoid inserting aggressive code in this case, instead
indvars should be fixed to be more aggressive in the face of lcssa phi's.

llvm-svn: 28850
2006-06-17 01:02:31 +00:00
Chris Lattner
9c37f23645 Fix a crash building 176.gcc due to my recent patch, which only fixed
half the problem.

llvm-svn: 24414
2005-11-18 18:30:47 +00:00
Chris Lattner
bca0be812d This was checking the wrong GEP expression. Fixing this fixes a gccas crash
compiling mysql reported by Ted Kremenek.

llvm-svn: 24402
2005-11-17 19:35:42 +00:00
Chris Lattner
677d85784a Allow indvar simplify to canonicalize ANY affine IV, not just affine IVs with
constant stride.  This implements Transforms/IndVarsSimplify/variable-stride-ivs.ll

llvm-svn: 22744
2005-08-10 01:12:06 +00:00
Nate Begeman
2bca4d9b7b Break SCEVExpander out of IndVarSimplify into its own .h/.cpp file so that
other passes may use it.

llvm-svn: 22557
2005-07-30 00:12:19 +00:00
Chris Lattner
df81539278 Fix PR582. The rewriter can move casts around, which invalidated the
BB iterator.  This fixes Transforms/IndVarsSimplify/2005-06-15-InstMoveCrash.ll

llvm-svn: 22221
2005-06-15 21:29:31 +00:00
Misha Brukman
b1c9317bb4 Remove trailing whitespace
llvm-svn: 21427
2005-04-21 23:48:37 +00:00
Chris Lattner
31f3382b3b Fix the second bug attached to PR504.
llvm-svn: 20181
2005-02-14 20:11:45 +00:00
Chris Lattner
e616fea3bc Fix for testcase Transforms/IndVarsSimplify/2005-02-11-InvokeCrash.ll
and PR504.

llvm-svn: 20129
2005-02-12 03:26:49 +00:00
Chris Lattner
7dfc2d29ac Convert 'struct' to 'class' in various places to adhere to the coding standards
and work better with VC++.  Patch contributed by Morten Ofstad!

llvm-svn: 17281
2004-10-27 16:14:51 +00:00
Chris Lattner
7cabf6f87a Fix a REALLY obscure bug in my previous checkin, which was splicing the END
marker from one ilist into the middle of another basic block!

llvm-svn: 16925
2004-10-12 01:02:29 +00:00
Chris Lattner
9776f7259b Handle a common case more carefully. In particular, instead of transforming
pointer recurrences into expressions from this:

  %P_addr.0.i.0 = phi sbyte* [ getelementptr ([8 x sbyte]* %.str_1, int 0, int 0), %entry ], [ %inc.0.i, %no_exit.i ]
  %inc.0.i = getelementptr sbyte* %P_addr.0.i.0, int 1            ; <sbyte*> [#uses=2]

into this:

  %inc.0.i = getelementptr sbyte* getelementptr ([8 x sbyte]* %.str_1, int 0, int 0), int %inc.0.i.rec

Actually create something nice, like this:

  %inc.0.i = getelementptr [8 x sbyte]* %.str_1, int 0, int %inc.0.i.rec

llvm-svn: 16924
2004-10-11 23:06:50 +00:00
Chris Lattner
3e86084641 Prototype these functions more accurately
llvm-svn: 16432
2004-09-20 04:43:15 +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
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
Chris Lattner
e5ad26dbb3 Throttle back indvar substitution from creating multiplies in loops. This is bad bad bad.
llvm-svn: 15227
2004-07-26 02:47:12 +00:00
Chris Lattner
7a002d6010 Two fixes. First, stop using the ugly shouldSubstituteIndVar method.
Second, disable substitution of quadratic addrec expressions to avoid putting
multiplies in loops!

llvm-svn: 14358
2004-06-24 06:49:18 +00:00
Chris Lattner
c9e06336ab Make use of BinaryOperator::create* methods to shrinkify code.
llvm-svn: 14262
2004-06-20 05:04:01 +00:00
Chris Lattner
4027500e1c Fix a nasty bug, noticed by Reid
llvm-svn: 14249
2004-06-19 18:15:50 +00:00
Chris Lattner
83cd87efcd Move the scev expansion code into this pass, where it belongs. There is
still room for cleanup, but at least the code modification is out of the
analysis now.

llvm-svn: 13135
2004-04-23 21:29:48 +00:00
Chris Lattner
c27302c79f Disable a previous patch that was causing indvars to loop infinitely :(
llvm-svn: 13108
2004-04-22 15:12:36 +00:00
Chris Lattner
c1a682dda0 Fix an extremely serious thinko I made in revision 1.60 of this file.
llvm-svn: 13106
2004-04-22 14:59:40 +00:00
Chris Lattner
af532f27e7 Implement a todo, rewriting all possible scev expressions inside of the
loop.  This eliminates the extra add from the previous case, but it's
not clear that this will be a performance win overall.  Tommorows test
results will tell. :)

llvm-svn: 13103
2004-04-21 23:36:08 +00:00
Chris Lattner
dc7cc35088 Implement a fixme. The helps loops that have induction variables of different
types in them.  Instead of creating an induction variable for all types, it
creates a single induction variable and casts to the other sizes.  This generates
this code:

no_exit:                ; preds = %entry, %no_exit
        %indvar = phi uint [ %indvar.next, %no_exit ], [ 0, %entry ]            ; <uint> [#uses=4]
***     %j.0.0 = cast uint %indvar to short             ; <short> [#uses=1]
        %indvar = cast uint %indvar to int              ; <int> [#uses=1]
        %tmp.7 = getelementptr short* %P, uint %indvar          ; <short*> [#uses=1]
        store short %j.0.0, short* %tmp.7
        %inc.0 = add int %indvar, 1             ; <int> [#uses=2]
        %tmp.2 = setlt int %inc.0, %N           ; <bool> [#uses=1]
        %indvar.next = add uint %indvar, 1              ; <uint> [#uses=1]
        br bool %tmp.2, label %no_exit, label %loopexit

instead of:

no_exit:                ; preds = %entry, %no_exit
        %indvar = phi ushort [ %indvar.next, %no_exit ], [ 0, %entry ]          ; <ushort> [#uses=2]
***     %indvar = phi uint [ %indvar.next, %no_exit ], [ 0, %entry ]            ; <uint> [#uses=3]
        %indvar = cast uint %indvar to int              ; <int> [#uses=1]
        %indvar = cast ushort %indvar to short          ; <short> [#uses=1]
        %tmp.7 = getelementptr short* %P, uint %indvar          ; <short*> [#uses=1]
        store short %indvar, short* %tmp.7
        %inc.0 = add int %indvar, 1             ; <int> [#uses=2]
        %tmp.2 = setlt int %inc.0, %N           ; <bool> [#uses=1]
        %indvar.next = add uint %indvar, 1
***     %indvar.next = add ushort %indvar, 1
        br bool %tmp.2, label %no_exit, label %loopexit

This is an improvement in register pressure, but probably doesn't happen that
often.

The more important fix will be to get rid of the redundant add.

llvm-svn: 13101
2004-04-21 22:22:01 +00:00
Chris Lattner
d72c3eb54e Change the ExitBlocks list from being explicitly contained in the Loop
structure to being dynamically computed on demand.  This makes updating
loop information MUCH easier.

llvm-svn: 13045
2004-04-18 22:14:10 +00:00
Chris Lattner
a814080025 If the loop executes a constant number of times, try a bit harder to replace
exit values.

llvm-svn: 13018
2004-04-17 18:44:09 +00:00
Chris Lattner
885a6eb74d Even if there are not any induction variables in the loop, if we can compute
the trip count for the loop, insert one so that we can canonicalize the exit
condition.

llvm-svn: 13015
2004-04-17 18:08:33 +00:00
Chris Lattner
9e9b2b7474 Fix some of the strange CBE-only failures that happened last night.
llvm-svn: 12980
2004-04-16 06:03:17 +00:00
Chris Lattner
d7a559e353 Fix a bug in the previous checkin: if the exit block is not the same as
the back-edge block, we must check the preincremented value.

llvm-svn: 12968
2004-04-15 20:26:22 +00:00
Chris Lattner
0cec5cb92c Change the canonical induction variable that we insert.
Instead of producing code like this:

Loop:
  X = phi 0, X2
  ...

  X2 = X + 1
  if (X != N-1) goto Loop

We now generate code that looks like this:

Loop:
  X = phi 0, X2
  ...

  X2 = X + 1
  if (X2 != N) goto Loop

This has two big advantages:
  1. The trip count of the loop is now explicit in the code, allowing
     the direct implementation of Loop::getTripCount()
  2. This reduces register pressure in the loop, and allows X and X2 to be
     put into the same register.

As a consequence of the second point, the code we generate for loops went
from:

.LBB2:  # no_exit.1
	...
        mov %EDI, %ESI
        inc %EDI
        cmp %ESI, 2
        mov %ESI, %EDI
        jne .LBB2 # PC rel: no_exit.1

To:

.LBB2:  # no_exit.1
	...
        inc %ESI
        cmp %ESI, 3
        jne .LBB2 # PC rel: no_exit.1

... which has two fewer moves, and uses one less register.

llvm-svn: 12961
2004-04-15 15:21:43 +00:00
Chris Lattner
e61b67d7d5 Rewrite the indvars pass to use the ScalarEvolution analysis.
This also implements some new features for the indvars pass, including
linear function test replacement, exit value substitution, and it works with
a much more general class of induction variables and loops.

llvm-svn: 12620
2004-04-02 20:24:31 +00:00
Chris Lattner
59d2d7fc33 Improve encapsulation in the Loop and LoopInfo classes by eliminating the
getSubLoops/getTopLevelLoops methods, replacing them with iterator-based
accessors.

llvm-svn: 10714
2004-01-08 00:09:44 +00:00
Chris Lattner
7e755e443f More minor non-functional changes. This now computes the exit condition, though
it doesn't do anything with it.

llvm-svn: 10590
2003-12-23 07:47:09 +00:00
Chris Lattner
a02d5aa6ce Don't mind me, I'm just refactoring away. This patch makes room for LFTR, but
contains no functionality changes.

llvm-svn: 10583
2003-12-22 09:53:29 +00:00
Chris Lattner
6449dcefbc Implement IndVarsSimplify/pointer-indvars.ll, transforming pointer
arithmetic into "array subscripts"

llvm-svn: 10580
2003-12-22 05:02:01 +00:00
Chris Lattner
d3678bc7c5 Fix PR194
llvm-svn: 10573
2003-12-22 03:58:44 +00:00
John Criswell
b22e9b4b35 Reverted back to previous revision - this was previously merged
according to the CVS log messages.

llvm-svn: 10517
2003-12-18 17:19:19 +00:00
John Criswell
86a3a48697 Merged in RELEASE_11.
llvm-svn: 10516
2003-12-18 16:43:17 +00:00
Chris Lattner
6c08bb8b8e Fix for PR185 & IndVarsSimplify/2003-12-15-Crash.llx
llvm-svn: 10473
2003-12-15 17:34:02 +00:00
Chris Lattner
713907e2b8 Fix bug: IndVarsSimplify/2003-12-10-RemoveInstrCrash.llx
llvm-svn: 10385
2003-12-10 20:43:04 +00:00
Chris Lattner
ccd9f3c1f8 Finegrainify namespacification
Reorder #includes
Implement: IndVarsSimplify/2003-12-10-IndVarDeadCode.ll

llvm-svn: 10376
2003-12-10 18:06:47 +00:00
Brian Gaeke
960707c335 Put all LLVM code into the llvm namespace, as per bug 109.
llvm-svn: 9903
2003-11-11 22:41:34 +00:00
John Criswell
482202a601 Added LLVM project notice to the top of every C++ source file.
Header files will be on the way.

llvm-svn: 9298
2003-10-20 19:43:21 +00:00
Chris Lattner
72272a70b8 Rename loop preheaders pass to loop simplify
llvm-svn: 9061
2003-10-12 21:52:28 +00:00
Misha Brukman
8b2bd4ed47 Fix spelling.
llvm-svn: 9027
2003-10-10 17:57:28 +00:00