Commit Graph

4522 Commits

Author SHA1 Message Date
Chris Lattner 7bdaecb7f4 Zap sitofp/fptoui pairs. In all cases when the sign difference
matters, the result is undefined anyway.

llvm-svn: 54396
2008-08-06 05:13:06 +00:00
Nick Lewycky bf42893567 Reinstate this optimization, but without the miscompile. Thanks to Bill for
tracking down that this was breaking llvm-gcc bootstrap on Linux.

llvm-svn: 54394
2008-08-06 04:54:03 +00:00
Dan Gohman 1fcc804cfd Pass the computed iteration count value to RewriteLoopExitValues
instead of having it call getIterationCount again.

llvm-svn: 54380
2008-08-05 22:34:21 +00:00
Bill Wendling ee12a7aeff Revert r53282. This was causing a miscompile on Linux. Also, the transformation
looks bogus. Please see PR2629 for details on why this is breaking things.

llvm-svn: 54372
2008-08-05 21:23:45 +00:00
Dan Gohman 3da016d137 Trim #includes.
llvm-svn: 54350
2008-08-05 15:32:23 +00:00
Duncan Sands c1e48b582d Fix comment typos.
llvm-svn: 54266
2008-08-01 12:23:49 +00:00
Nate Begeman fecbc8cff1 Add vector shifts to the IR, patch by Eli Friedman.
CodeGen & Clang work coming next.

llvm-svn: 54161
2008-07-29 15:49:41 +00:00
Matthijs Kooijman 98b5c16e3b Add -unroll-allow-partial command line option that enabled the loop unroller to
partially unroll a loop when fully unrolling would not fit under the threshold.

Patch by Mikael Lepistö.

llvm-svn: 54160
2008-07-29 13:21:23 +00:00
Matthijs Kooijman fd3070459b Restructure ArgumentPromotion a bit. Instead of just having a single boolean
that says "unconditional loads from this argument are safe", we now keep track
of the safety per set of indices from which loads happen. This prevents
ArgPromotion from promoting loads that aren't really valid. As an added effect,
this will now disregard the the type of the indices passed to a GEP, so
"load GEP %A, i32 1" and "load GEP %A, i64 1" will result in a single argument,
not two.

This fixes PR2598, for which a testcase has been added as well.

llvm-svn: 54159
2008-07-29 10:00:13 +00:00
Owen Anderson 813bf7af7f Don't remove volatile loads. Thanks to Duncan for noticing this one.
llvm-svn: 54144
2008-07-28 20:52:42 +00:00
Owen Anderson 3f3389745d Add support for eliminating stores that store the same value that was just loaded.
This fixes PR2599.

llvm-svn: 54133
2008-07-28 16:14:26 +00:00
Dan Gohman 2ce6f2ad5e Rename SDOperand to SDValue.
llvm-svn: 54128
2008-07-27 21:46:04 +00:00
Dan Gohman 5f36a32e7b Put the LICM of constant GlobalVariables, introduced in r53945, under a
command-line option, and disable it by default. It introduced performance
regressions because CodeGen is currently not able to remat such loads.

llvm-svn: 53997
2008-07-24 23:57:25 +00:00
Chris Lattner 8a8fb908dc "Allow LICM to sink or lift loads from constant memory. Also add a test
case for this.

This allows instructions like loads from global variables declared to
be constant to be moved out of loops."

Patch by Stefanus Du Toit!

llvm-svn: 53945
2008-07-23 05:06:28 +00:00
Dan Gohman fa1211f69b Enable first-class aggregates support.
Remove the GetResultInst instruction. It is still accepted in LLVM assembly
and bitcode, where it is now auto-upgraded to ExtractValueInst. Also, remove
support for return instructions with multiple values. These are auto-upgraded
to use InsertValueInst instructions.

The IRBuilder still accepts multiple-value returns, and auto-upgrades them
to InsertValueInst instructions.

llvm-svn: 53941
2008-07-23 00:34:11 +00:00
Dan Gohman 7ad3cd8c9d Fix a bug in LSR's dead-PHI cleanup. If a PHI has a def-use chain that
leads into a cycle involving a different PHI, LSR got stuck running
around that cycle looking for the original PHI. To avoid this, keep
track of visited PHIs and stop searching if we see one more than once.
This fixes PR2570.

llvm-svn: 53879
2008-07-21 21:45:02 +00:00
Duncan Sands 2c741145a7 Supress a gcc-4.3 warning.
llvm-svn: 53771
2008-07-18 21:06:02 +00:00
Owen Anderson 04a6e0ba8c Make PRE actually handle critical edges (by splitting them). Confirmed that bootstrap passes with this change.
llvm-svn: 53762
2008-07-18 18:03:38 +00:00
Owen Anderson 9858691f25 Reapply r53735. My last patch fixed the failures Dan observed.
llvm-svn: 53761
2008-07-18 17:49:43 +00:00
Owen Anderson 1468bec06e Add some checks that got lost in the shuffle. This fixes 464.h264ref.
llvm-svn: 53760
2008-07-18 17:46:41 +00:00
Dan Gohman 29c3adaae0 Revert r53735. It broke SPEC 464.h264ref.
llvm-svn: 53757
2008-07-18 16:44:49 +00:00
Owen Anderson fd7102037d Use MergeBlockIntoPredecessor to simplify some code.
llvm-svn: 53735
2008-07-17 20:00:46 +00:00
Owen Anderson 27405efdc0 Make MergeBlockIntoPredecessor more aggressive when the same successor appears
more than once.

llvm-svn: 53731
2008-07-17 19:42:29 +00:00
Owen Anderson addbe3eed1 Enable PRE. My last batch of changes fixed the miscompile.
llvm-svn: 53730
2008-07-17 19:41:00 +00:00
Matthijs Kooijman 8b69d77a7a Make GlobalOpt preserve address spaces when scalar replacing aggregate globals.
llvm-svn: 53716
2008-07-17 11:59:53 +00:00
Chris Lattner c600c53d1f Fix PR2553
llvm-svn: 53715
2008-07-17 06:07:20 +00:00
Evan Cheng 97cd0298cc Inliner tweak. Function calls should cost more than one instruction!
llvm-svn: 53712
2008-07-17 01:31:49 +00:00
Owen Anderson c062381c7b Factor MergeBlockIntoPredecessor out into BasicBlockUtils.
llvm-svn: 53705
2008-07-17 00:01:40 +00:00
Owen Anderson ac31096311 There's no need to iterate block merging and PRE. In fact, iterating the latter
could cause problems for memdep when it breaks critical edges.

llvm-svn: 53691
2008-07-16 17:52:31 +00:00
Matthijs Kooijman c1d7477ed2 Redo InstCombiner::visitExtractValueInst. Instead of using the (complicate)
FindInsertedValue, it now performs a number of simple transformations that
should result in the same effect when applied iteratively.

llvm-svn: 53673
2008-07-16 12:55:45 +00:00
Evan Cheng c97094552c Fix PR2296. Do not transform x86_sse2_storel_dq into a full-width store.
llvm-svn: 53666
2008-07-16 07:28:14 +00:00
Owen Anderson 24768e3dc4 Revert this, as it seems to still be broken.
llvm-svn: 53627
2008-07-15 17:59:02 +00:00
Owen Anderson 9d1f497a28 Enable local PRE by default.
llvm-svn: 53616
2008-07-15 16:28:23 +00:00
Owen Anderson 53d546e40b Have GVN do a pre-pass over the CFG that folds away unconditional branches where possible. This allows local PRE to be more aggressive.
llvm-svn: 53615
2008-07-15 16:28:06 +00:00
Matthijs Kooijman c893bf472d Allow deadargelim to change return types even though now values were dead. This
again canonicalizes {i32} into i32 and {} into void.

llvm-svn: 53610
2008-07-15 14:42:31 +00:00
Matthijs Kooijman 5e8c022e21 Revert r53606. It turns out that explicitely tracking the liveness of the
return value as a whole in deadargelim is really not needed now that we simply
rebuild the old return value and actually prevents some canonicalization from
taking place.

This revert stops deadargelim from changing {i32} into i32 for now, but I'll
fix that next.

llvm-svn: 53609
2008-07-15 14:39:36 +00:00
Matthijs Kooijman c1da874478 Make deadargelim a bit less smart, so it doesn't choke on nested structs as
return values that are still (partially) live. Instead of updating all uses of
a call instruction after removing some elements, it now just rebuilds the
original struct (With undef gaps where the unused values were) and leaves it to
instcombine to clean this up.

The added testcase still fails currently, but this is due to instcombine which
isn't good enough yet. I will fix that part next.

llvm-svn: 53608
2008-07-15 14:03:10 +00:00
Matthijs Kooijman 04d4c328ac Don't use isa when we can reuse a previous dyn_cast.
llvm-svn: 53607
2008-07-15 13:39:08 +00:00
Matthijs Kooijman 84194b6768 Make DeadArgElim keep liveness of the return value as a whole in addition to
only the liveness of partial return values (for functions returning a struct).
This is more explicit to prevent unwanted changes in the return value. 

In particular, deadargelim now canonicalizes a function returning {i32} to
returning i32 and {} to void, if the struct returned is not used in its
entirety, but only the single element is used.

llvm-svn: 53606
2008-07-15 13:36:06 +00:00
Matthijs Kooijman 79a8eb547c Let DAE keep a list of live functions, instead of simply marking all arguments
and return values live for those functions. This doesn't change anything yet,
but prepares for the coming commits.

llvm-svn: 53601
2008-07-15 09:11:16 +00:00
Matthijs Kooijman e9af814669 Split DAE::MarkLive into MarkLive and PropagateLiveness.
llvm-svn: 53600
2008-07-15 09:00:17 +00:00
Matthijs Kooijman 2ce5709e31 Pass around const RetOrArg references instead of copying values. Also, mark
RetOrArg::getDescription() as const.

llvm-svn: 53599
2008-07-15 08:56:49 +00:00
Matthijs Kooijman f2860b9fb3 Simplify debug code by using RetOrArg::getDescription().
llvm-svn: 53598
2008-07-15 08:53:36 +00:00
Matthijs Kooijman 90d08addb0 Fix indentation (intentionally left out of the previous commit).
llvm-svn: 53592
2008-07-15 08:47:32 +00:00
Matthijs Kooijman 06642d3812 Move the deadargelim code for intrinsically alive functions into its own
method, to slightly simplify control flow.

llvm-svn: 53591
2008-07-15 08:45:12 +00:00
Dan Gohman 162668fa78 Fix uninitialized use of the Changed variable.
llvm-svn: 53564
2008-07-14 17:55:01 +00:00
Chris Lattner 8882b1c41c Reapply r53540, now with the matching header!
llvm-svn: 53557
2008-07-14 17:32:59 +00:00
Duncan Sands 68b0383057 Revert r53540 - it does not compile.
llvm-svn: 53549
2008-07-14 07:59:28 +00:00
Chris Lattner 2831ad28be If a function calls setjmp, never inline it into other functions. This is
a hack around the fact that we don't represent the CFG correctly for sj/lj.
It fixes PR2486.

llvm-svn: 53540
2008-07-14 00:46:56 +00:00
Chris Lattner 6f5ea6e49c simplify some code, shuffle and insertelt always return a vector.
llvm-svn: 53538
2008-07-14 00:32:20 +00:00
Chris Lattner 16395e51f4 Fix PR2506 by being a bit more careful about reverse fact propagation when
disproving a condition.  This actually compiles the existing testcase
(udiv_select_to_select_shift) to:

define i64 @test(i64 %X, i1 %Cond) {
entry:
	%divisor1.t = lshr i64 %X, 3		; <i64> [#uses=1]
	%quotient2 = lshr i64 %X, 3		; <i64> [#uses=1]
	%sum = add i64 %divisor1.t, %quotient2		; <i64> [#uses=1]
	ret i64 %sum
}

instead of:

define i64 @test(i64 %X, i1 %Cond) {
entry:
	%quotient1.v = select i1 %Cond, i64 3, i64 4		; <i64> [#uses=1]
	%quotient1 = lshr i64 %X, %quotient1.v		; <i64> [#uses=1]
	%quotient2 = lshr i64 %X, 3		; <i64> [#uses=1]
	%sum = add i64 %quotient1, %quotient2		; <i64> [#uses=1]
	ret i64 %sum
}

llvm-svn: 53534
2008-07-14 00:15:52 +00:00
Chris Lattner 80b03a1b49 Fix mishandling of the infinite loop case when merging two blocks. This
fixes PR2540.

llvm-svn: 53533
2008-07-13 22:23:11 +00:00
Chris Lattner 834ab4ec1b more refactoring. Use early exits instead of really complex logic.
No functionality change.

llvm-svn: 53532
2008-07-13 22:04:41 +00:00
Chris Lattner 5eed37224a improve comments.
llvm-svn: 53531
2008-07-13 21:55:46 +00:00
Chris Lattner 9aada1d755 factor another large hunk of code out into its own function.
No functionality change.

llvm-svn: 53530
2008-07-13 21:53:26 +00:00
Chris Lattner 55eaae1e0c Final bit of simplification for FoldBranchToCommonDest.
llvm-svn: 53528
2008-07-13 21:20:19 +00:00
Chris Lattner 1b317ea48a simplify logic a bit
llvm-svn: 53527
2008-07-13 21:15:11 +00:00
Chris Lattner 2e25b8f444 Refactor some code out into its own helper function, getting rid of crazy multiline
conditionals and commenting the code better.

No functionality change.

llvm-svn: 53526
2008-07-13 21:12:01 +00:00
Nick Lewycky f76aa23b54 Enhance analysis of srem.
Remove dead code analyzing urem. 'urem' of power-of-2 is canonicalized to an
'and' instruction.

llvm-svn: 53506
2008-07-12 05:04:38 +00:00
Dan Gohman 3707f1daba Use find instead of lower_bound.
llvm-svn: 53474
2008-07-11 20:58:19 +00:00
Owen Anderson 8e462e9a82 Don't call lookupNumber more than we have to.
llvm-svn: 53470
2008-07-11 20:05:13 +00:00
Nick Lewycky 45e127ab20 Document 'mask' in this calculation.
llvm-svn: 53454
2008-07-11 08:16:26 +00:00
Nick Lewycky da405e1155 Remove misleading constant from comment.
llvm-svn: 53452
2008-07-11 07:36:19 +00:00
Nick Lewycky f95b64acaa Add another optimization from PR2330. Also catch some missing cases that are
similar.

llvm-svn: 53451
2008-07-11 07:20:53 +00:00
Chris Lattner 3994bed1a9 a missed optimization that Eli spotted
llvm-svn: 53449
2008-07-11 06:40:29 +00:00
Chris Lattner 13a6911ea2 another bug in the same line.
llvm-svn: 53448
2008-07-11 06:38:16 +00:00
Chris Lattner de89b507dd fix a bug spotted by Eli's eagle eyes
llvm-svn: 53447
2008-07-11 06:36:01 +00:00
Chris Lattner bd25b8507c simplify and merge a bunch of code. Instead of comparing against
the min/max values for an integer type, compare against the min/max
values we can prove contain the input.  This might be a tighter bound,
so this is general goodness.

llvm-svn: 53446
2008-07-11 05:40:05 +00:00
Chris Lattner 38a50c9528 fold away (x <= cst) earlier, allowing us to not have to
handle them in some code.

llvm-svn: 53445
2008-07-11 05:08:55 +00:00
Chris Lattner 6af608b8ce Fix folding of icmp's of i1 where the comparison is signed. The code
was using the algorithm for folding unsigned comparisons which is
completely wrong.  This has been broken since the signless types change.

llvm-svn: 53444
2008-07-11 04:20:58 +00:00
Chris Lattner 4fa8bb3430 Fix a bogus optimization: folding (slt (zext i1 A to i32), 1) -> (slt i1 A, true)
This cause a regression in InstCombine/JavaCompare, which was doing the right
thing on accident.  To handle the missed case, generalize the comparisons based
on masked bits a little bit to handle comparisons against the max value. For 
example, we can now xform (slt i32 (and X, 4), 4) -> (setne i32 (and X, 4), 4)

llvm-svn: 53443
2008-07-11 04:09:09 +00:00
Matthijs Kooijman e0f3ab82c4 Restructure dead argument elimination, try #3 :-)
Rewrite the DeadArgumentElimination pass, to use a more explicit tracking of
dependencies between return values and/or arguments. Also make the handling of
arguments and return values the same.

The pass now looks properly inside returned structs, but only at the first
level (ie, not inside nested structs).

This version fixed a few more bugs and was cleaned up a bit. It now passes all
of LLVM's testing, and should still pass SPEC2006. There is still a minor bug
with regard to returning nested structs. Since there is currently nothing that
emits such IR, I will fix that in a seperate commit (partly because it requires
a non-trivial fix).

llvm-svn: 53400
2008-07-10 10:24:08 +00:00
Nick Lewycky 6193a564ab Fix overzealous optimization. Thanks to Duncan Sands for pointing out my error!
llvm-svn: 53393
2008-07-10 05:51:40 +00:00
Nick Lewycky bb89c2a3f6 Simplify, suggested by Chris Lattner.
llvm-svn: 53283
2008-07-09 07:35:26 +00:00
Nick Lewycky f9c27c343a Fold (a < 8) && (b < 8) into (a|b) < 8 for unsigned less or greater than.
llvm-svn: 53282
2008-07-09 07:29:11 +00:00
Nick Lewycky 364661c43e Fold ((1 << a) & 1) to (a == 0).
llvm-svn: 53276
2008-07-09 05:20:13 +00:00
Nick Lewycky 0d3645e673 Reduce x - y to -y when we know the 'x' part will get masked off anyways.
llvm-svn: 53271
2008-07-09 04:32:37 +00:00
Devang Patel 51cbf928ab If loop induction variable's start value is less then its exit value then do not split the loop.
llvm-svn: 53265
2008-07-09 00:12:01 +00:00
Chris Lattner 501d78fdc0 Fix PR2496, a really nasty bug which involved sinking volatile loads
into phis.  This is actually the same bug as PR2262 /
2008-04-29-VolatileLoadDontMerge.ll, but I missed checking the first 
predecessor for multiple successors.  Testcase here:
InstCombine/2008-07-08-VolatileLoadMerge.ll

llvm-svn: 53240
2008-07-08 17:18:32 +00:00
Evan Cheng 03001cb820 Fix two serious LSR bugs.
1. LSR runOnLoop is always returning false regardless if any transformation is made.
2. AddUsersIfInteresting can create new instructions that are added to DeadInsts. But there is a later early exit which prevents them from being freed.

llvm-svn: 53193
2008-07-07 19:51:32 +00:00
Dan Gohman 38740a98b2 Make DenseMap's insert return a pair, to more closely resemble std::map.
llvm-svn: 53177
2008-07-07 17:46:23 +00:00
Nick Lewycky 9f1a4dc672 Fix missed optimization opportunity when analyzing cast of mul and select.
llvm-svn: 53151
2008-07-05 21:19:34 +00:00
Owen Anderson 3ea90a7d55 Use information already present in the ValueTable to fast-fail when we know there won't be a value number match. This speeds up GVN on a case where there are very few redundancies by ~25%.
llvm-svn: 53108
2008-07-03 17:44:33 +00:00
Devang Patel eb611ddeb2 Do not try to update dominator info while manipulating CFG. This code does not handle all cases and keeps invalid dom info around some cases, which misleads other passes down stream.
Right now, dom info is recaluclated in the end if the loop is switched.

llvm-svn: 53106
2008-07-03 17:37:52 +00:00
Owen Anderson d57cdc3c60 Remove the ability for ADCE to remove unreachable blocks in loop nests, because, as Eli pointed out, SimplifyCFG already does this.
llvm-svn: 53104
2008-07-03 17:21:41 +00:00
Bill Wendling a96eabaab7 Remove unused function.
llvm-svn: 53090
2008-07-03 07:10:03 +00:00
Devang Patel f94b9826b5 Preserve dom info.
llvm-svn: 53089
2008-07-03 07:04:22 +00:00
Devang Patel 226edd1826 Remove extra FIXME
llvm-svn: 53087
2008-07-03 06:50:04 +00:00
Devang Patel c4dcf82a16 Reconstruct dom info, if loop is unswitched.
llvm-svn: 53086
2008-07-03 06:48:21 +00:00
Devang Patel e491bb8845 LoopUnswitch does not preserve dominator info in all cases.
llvm-svn: 53085
2008-07-03 05:55:03 +00:00
Devang Patel 7dcfff392a Undo previous patch. It is not that simple to fix dom info here.
llvm-svn: 53062
2008-07-03 00:08:13 +00:00
Devang Patel 5adfcb5783 Preserve dom info while simplifing loop after the unswitch.
llvm-svn: 53052
2008-07-02 22:58:54 +00:00
Owen Anderson 488b89f608 Use df_ext_iterator to capture the reachable set without allocating an extra set.
Also, move large sets and vectors out of instance variables and onto the stack,
and give them more reasonable sizes.

llvm-svn: 53044
2008-07-02 18:41:09 +00:00
Owen Anderson 6acc782dad Avoid a redundant call.
llvm-svn: 53040
2008-07-02 18:15:31 +00:00
Owen Anderson 323b5755a6 Add support to ADCE for pruning unreachable blocks. This addresses the final
part of PR2509.

llvm-svn: 53038
2008-07-02 18:05:19 +00:00
Owen Anderson 9edcf24da9 Use DenseSet rather than SmallPtrSet for the alive set. Using SmallPtrSet
with a huge "size" parameter is actually quite inefficient.

llvm-svn: 53034
2008-07-02 17:32:04 +00:00
Owen Anderson b22a640fe4 A better fix for PR2503 that doesn't pessimize GVN in the presence of unreachable blocks.
llvm-svn: 53032
2008-07-02 17:20:16 +00:00
Devang Patel ed50fb5b61 reuse vectors.
llvm-svn: 53007
2008-07-02 01:44:29 +00:00
Devang Patel 57d94d6304 Fix comment.
llvm-svn: 53006
2008-07-02 01:31:19 +00:00
Devang Patel e149d4ed4d Preserve loop data so that it is not fetched everytime it is needed.
Keep track of currentLoop.

llvm-svn: 53005
2008-07-02 01:18:13 +00:00
Evan Cheng da3db11db3 - Re-apply 52748 and friends with fix. GetConstantStringInfo() returns an empty string for ConstantAggregateZero case which surprises selectiondag.
- Correctly handle memcpy from constant string which is zero-initialized.

llvm-svn: 52891
2008-06-30 07:31:25 +00:00
Anton Korobeynikov a7c583d584 Revert (52748 and friends):
Move GetConstantStringInfo to lib/Analysis. Remove
string output routine from Constant. Update all
callers. Change debug intrinsic api slightly to
accomodate move of routine, these now return values
instead of strings.

This unbreaks llvm-gcc bootstrap.

llvm-svn: 52884
2008-06-29 17:57:03 +00:00
Eric Christopher 3f1c75c4d8 Remove unused function.
llvm-svn: 52749
2008-06-26 01:19:35 +00:00
Eric Christopher d0ab9c47e6 Move GetConstantStringInfo to lib/Analysis. Remove
string output routine from Constant. Update all
callers. Change debug intrinsic api slightly to
accomodate move of routine, these now return values
instead of strings.

llvm-svn: 52748
2008-06-26 00:31:12 +00:00
Evan Cheng 88ca48b09d Restore DeadArgElim back to 52570. It's breaking 447.dealII.
llvm-svn: 52736
2008-06-25 18:10:09 +00:00
Duncan Sands 1b03c2ac98 Pacify gcc-4.3.
llvm-svn: 52723
2008-06-25 16:31:18 +00:00
Matthijs Kooijman 2e2001d8b9 Fix a (false) warning on darwin.
llvm-svn: 52705
2008-06-25 08:12:16 +00:00
Matthijs Kooijman 4e1cf1e7d7 Fix some cosmetics in comments.
llvm-svn: 52704
2008-06-25 08:10:21 +00:00
Evan Cheng 5fd28b54c7 - Use O(1) check of basic block size limit.
- Avoid speculatively execute vector ops.

llvm-svn: 52703
2008-06-25 07:50:12 +00:00
Chris Lattner c9c81fb0df Fix PR2488, a case where we deleted stack restores too aggressively.
llvm-svn: 52702
2008-06-25 05:59:28 +00:00
Dan Gohman 04c8bd7e11 Revert 52645, the loop unroller changes. It caused a regression in 252.eon.
llvm-svn: 52688
2008-06-24 20:44:42 +00:00
Dan Gohman 4be44e62b3 Fix a typo in a comment.
llvm-svn: 52687
2008-06-24 18:00:21 +00:00
Matthijs Kooijman c702e1d32f Commit the new DeadArgElim pass again, this time with the gcc bootstrap failures fixed.
Also add a testcase to reproduce the gcc bootstrap failure in very much reduced form.

llvm-svn: 52677
2008-06-24 16:30:26 +00:00
Matthijs Kooijman 19a6469e1b Rename a few variables to be more consistent.
llvm-svn: 52672
2008-06-24 09:14:10 +00:00
Dan Gohman abd8f41c81 Use use_empty() instead of getNumUses(), avoiding a use list traversal.
llvm-svn: 52651
2008-06-23 23:23:49 +00:00
Dan Gohman ac563833ae Fix spelling and grammar in a comment.
llvm-svn: 52648
2008-06-23 22:11:52 +00:00
Dan Gohman 48c5c7e860 Revamp the loop unroller, extending it to correctly update PHI nodes
in the presence of out-of-loop users of in-loop values and the trip
count is not a known multiple of the unroll count, and to be a bit
simpler overall. This fixes PR2253.

llvm-svn: 52645
2008-06-23 21:29:41 +00:00
Evan Cheng 403e567043 Disable PRE. It's breaking bootstrapping.
llvm-svn: 52643
2008-06-23 21:22:35 +00:00
Owen Anderson 54e02194a1 Tighten the conditions under which we do PRE, remove some unneeded code, and correct our preserved analyses list, since we
do now change the CFG by splitting critical edges during PRE.

llvm-svn: 52631
2008-06-23 17:49:45 +00:00
Chris Lattner 4d754bc97b minor tidying of comments.
llvm-svn: 52630
2008-06-23 17:11:23 +00:00
Owen Anderson 00fdbd01e5 At Chris' suggestion, move the liveness and worklist datastructures into
instance variables so they can be allocated just once, and reuse the worklist
as the dead list as well.

llvm-svn: 52618
2008-06-23 06:13:12 +00:00
Dan Gohman 5ca5e02480 Improve LSR's dead-phi detection to handle use-def cycles
with more than two nodes.

llvm-svn: 52617
2008-06-22 20:44:02 +00:00
Dan Gohman 90071075e2 Use Loop::block_iterator.
llvm-svn: 52616
2008-06-22 20:18:58 +00:00
Chris Lattner 6ff85681e4 Fix PR2369 by making scalarrepl more careful about promoting
structures.  Its default threshold is to promote things that are
smaller than 128 bytes, which is sane.  However, it is not sane
to do this for things that turn into 128 *registers*.  Add a cap
on the number of registers introduced, defaulting to 128/4=32.

llvm-svn: 52611
2008-06-22 17:46:21 +00:00
Eli Friedman d3449df326 Fix for PR2479: correctly optimize expressions like (a > 13) & (a ==
15).

See also PR1800, which is about the signed case.

llvm-svn: 52608
2008-06-21 23:36:13 +00:00
Dan Gohman 158ff2c4a9 Use Instruction::eraseFromParent().
llvm-svn: 52606
2008-06-21 22:08:46 +00:00
Chris Lattner 8459e0bc59 Fix warning when assertions disabled.
llvm-svn: 52590
2008-06-21 19:49:01 +00:00
Evan Cheng 42bbca11cc Enable PRE.
llvm-svn: 52574
2008-06-21 07:26:53 +00:00
Evan Cheng 33067210d1 Back out Matthijs' DAE patches. It's miscompiling gcc driver.
llvm-svn: 52570
2008-06-21 00:31:44 +00:00
Dan Gohman 3ada1e118b Clean up a use of std::distance.
llvm-svn: 52544
2008-06-20 17:11:32 +00:00
Dan Gohman a5dd67f002 Tidy up some commments and use the getAggregateOperand and
getInsertedValueOperand accessors. Thanks Matthijs!

llvm-svn: 52543
2008-06-20 16:41:17 +00:00
Dan Gohman b5210efb31 Fix the conditions under which SCCP should examine insertvalue
instructions. Thanks to Matthijs Kooijman for pointing this out!

llvm-svn: 52542
2008-06-20 16:39:44 +00:00
Matthijs Kooijman c456f9dfc6 80 column and trailing whitespace fixes.
llvm-svn: 52539
2008-06-20 15:34:07 +00:00
Matthijs Kooijman 0c50b953c5 Don't let DeadArgumentElimination attempt to update callers when the return
type wasn't changed.

llvm-svn: 52538
2008-06-20 15:25:43 +00:00
Matthijs Kooijman 9dc59b7666 Don't let DeadArgElimination change the return type ({} into void and {T}
into T) when no return values are actually dead.

llvm-svn: 52537
2008-06-20 15:16:45 +00:00
Matthijs Kooijman 013b6a9a42 Explicitely track if any arguments or return values were removed in
DeadArgumentElimination and assert that the function type does not change if
nothing was changed. This should catch subtle changes in function type that are
not intended.

llvm-svn: 52536
2008-06-20 14:28:52 +00:00
Matthijs Kooijman e91aed6ce1 Remove debug output.
llvm-svn: 52535
2008-06-20 14:03:35 +00:00
Matthijs Kooijman 8d32dee428 Recommit r52459, rewriting of the dead argument elimination pass.
This is a fixed version that no longer uses multimap::equal_range, which
resulted in a pointer invalidation problem.

Also, DAE::InspectedFunctions was not really necessary, so it got removed.

Lastly, this version no longer applies the extra arg hack on functions who did
not have any arguments to start with.

llvm-svn: 52532
2008-06-20 09:36:16 +00:00
Owen Anderson 78fbcafb53 Really disable PRE.
llvm-svn: 52531
2008-06-20 08:59:13 +00:00
Chris Lattner f3ecd2d290 Fix PR2471, which is a bug involving an invalid promotion from a conditional load.
llvm-svn: 52525
2008-06-20 05:12:56 +00:00
Owen Anderson 1b3ea963f7 Change around the data structures used to store availability sets, resulting in a GVN+PRE that is faster that GVN alone was before.
llvm-svn: 52521
2008-06-20 01:15:47 +00:00
Dan Gohman 041f9d03ff Teach SCCP about insertvalue and extractvalue, and about
propagating constants across aggregate return values when
insertvalue and extractvalue are used.

llvm-svn: 52520
2008-06-20 01:15:44 +00:00
Dan Gohman 3b18fd7b02 Teach InlineFunction how to differentiate between multiple-value
return statements and aggregate returns so that it handles both
correctly.

llvm-svn: 52519
2008-06-20 01:03:44 +00:00
Evan Cheng 9598f930f3 Disable PRE for now. It seems to be breaking llvm-gcc bootstrapping.
llvm-svn: 52518
2008-06-20 01:01:07 +00:00
Owen Anderson e780d66657 Add a hidden -disable-pre flag for testing purposes. This should be removed
once benchmarking is completed.

llvm-svn: 52506
2008-06-19 19:57:25 +00:00
Owen Anderson fdf9f168b5 PRE requires that critical edges be split.
llvm-svn: 52505
2008-06-19 19:54:19 +00:00
Bill Wendling cd6fb1d0a8 Remove dead code causing a warning.
llvm-svn: 52502
2008-06-19 18:00:44 +00:00
Dan Gohman d6530872f3 Use the common API for adding instructions to basic blocks instead of
using BasicBlock::getInstList.

llvm-svn: 52500
2008-06-19 17:53:32 +00:00
Owen Anderson ff21db851d Be sure to remove values from the value numbering table after we delete them.
This fixes a failure on povray.

llvm-svn: 52499
2008-06-19 17:53:26 +00:00
Dan Gohman ed2250990a Use Instruction::moveBefore instead of manipulating the instruction list
directly.

llvm-svn: 52498
2008-06-19 17:47:47 +00:00
Dan Gohman 9eea470fcf Avoid using BasicBlock::getInstList directly in a few places.
llvm-svn: 52497
2008-06-19 17:37:25 +00:00
Owen Anderson 45d3701fce Revert support for insertvalue and extractvalue instructions for the moment.
GVN expects that all inputs which to an instruction fall somewhere in the value
hierarchy, which isn't true for these.

llvm-svn: 52496
2008-06-19 17:25:39 +00:00
Dan Gohman 68f539e807 Delete dead code.
llvm-svn: 52494
2008-06-19 17:18:39 +00:00
Matthijs Kooijman 0c71732497 Use a CallSite to find the nth argument of a call/invoke instruction instead of
using getOperand() directly. This makes things work with invoke instructions as
well.

llvm-svn: 52489
2008-06-19 08:53:24 +00:00
Owen Anderson 3ea800fbad Add support for extractvalue and insertvalue instructions in GVN.
llvm-svn: 52472
2008-06-18 21:59:00 +00:00
Owen Anderson 6a903bc601 Add local PRE to GVN. This only operates in cases where it would not increase code size, namely when the instantiated expression
would only need to be created in one predecessor.

llvm-svn: 52471
2008-06-18 21:41:49 +00:00
Chris Lattner 78119b4742 Fix the regressions on sext-misc.ll my patch yesterday caused.
llvm-svn: 52466
2008-06-18 18:11:55 +00:00
Owen Anderson 9094cc957e Revert r52459, which was causing an infinite loop or massive slowdown on MultiSource/Applications/SPASS, and possibly others as well.
Please reapply once this is fixed.

llvm-svn: 52465
2008-06-18 17:32:16 +00:00
Dan Gohman be928e3b21 Move LSR's private isZero function to a public SCEV member
function, and make use of it in several places.

llvm-svn: 52463
2008-06-18 16:23:07 +00:00
Matthijs Kooijman 964557fdf5 Rewrite the DeadArgumentElimination pass, to use a more explicit tracking of
dependencies between return values and/or arguments. Also make the handling of
arguments and return values the same.

The pass now looks properly inside returned structs, but only at the first                                                                                     
level (ie, not inside nested structs).

Also add a testcase for testing various variations of (multiple) dead rerturn
values.

llvm-svn: 52459
2008-06-18 11:12:53 +00:00
Matthijs Kooijman fd17357643 Reapply r52397 (make IPConstProp promote returned arguments), but fixed this
time. Sorry for the trouble!

This time, also add a testcase, which I should have done in the first place...

llvm-svn: 52455
2008-06-18 08:30:37 +00:00
Matthijs Kooijman 97034598b1 Reapply r52396, it was unrelated to the breakage (that was caused by r52397, my
commit after this).

llvm-svn: 52453
2008-06-18 08:09:27 +00:00
Chris Lattner ef36dcd10b implement some simple bswap optimizations, rdar://5992453
llvm-svn: 52442
2008-06-18 04:33:20 +00:00
Chris Lattner b5ee8b3e89 make truncate/sext elimination capable of changing phi's. This
implements rdar://6013816 and the testcase in Transforms/InstCombine/sext-misc.ll.

llvm-svn: 52440
2008-06-18 04:00:49 +00:00
Devang Patel cd6b697945 Preserve dominance frontier while trivially unswitching loop.
llvm-svn: 52438
2008-06-18 02:16:38 +00:00
Owen Anderson 75f3732b23 We don't want to find dependencies within the same block in this case. It leads to incorrect results because
we're detecting something at or after the call we're querying on.

llvm-svn: 52433
2008-06-17 22:27:06 +00:00
Chris Lattner aecc3750d1 revert recent patch which is causing widespread breakage.
llvm-svn: 52415
2008-06-17 17:06:43 +00:00
Duncan Sands 4b50fde2c4 Fix typo that changed the logic to something wrong.
Spotted by Nick Lewycky.

llvm-svn: 52411
2008-06-17 15:55:30 +00:00
Matthijs Kooijman 332836d68d Learn IPConstProp to propagate arguments that are directly returned. Strictly
speaking these are not constant values. However, when a function always returns
one of its arguments, then from the point of view of each caller the return
value is constant (or at least a known value) and can be replaced.

llvm-svn: 52397
2008-06-17 12:20:24 +00:00
Matthijs Kooijman f03c1ae407 Learn IPConstProp to look at individual return values and propagate them
individually.

Also learn IPConstProp how returning first class aggregates work, in addition
to old style multiple return instructions.

Modify the return-constants testscase to confirm this behaviour.

llvm-svn: 52396
2008-06-17 12:02:52 +00:00
Dan Gohman ab0dccba6b Refine the change in r52258 for avoiding use-before-def conditions
when changing the stride of a comparison so that it's slightly
more precise, by having it scan the instruction list to determine
if there is a use of the condition after the point where the
condition will be inserted.

llvm-svn: 52371
2008-06-16 22:34:15 +00:00
Evan Cheng 319e9a4f63 Switch over to SetVector to ensure same order of iterations do not vary across runs.
llvm-svn: 52361
2008-06-16 21:08:17 +00:00
Evan Cheng a72cdcd1a2 Iterating over SmallPtrSet is not deterministic.
llvm-svn: 52339
2008-06-16 18:17:09 +00:00
Matthijs Kooijman 86cda9e050 Pass around Instruction* instead of Instruction& in FindInsertedValue and friends.
llvm-svn: 52318
2008-06-16 13:13:08 +00:00
Matthijs Kooijman 5cb387735d 80 column fixes.
llvm-svn: 52316
2008-06-16 12:57:37 +00:00
Matthijs Kooijman e92e18be5a Move FindScalarValue from InstructionCombining.cpp to ValueTracking.cpp. While
I'm at it, rename it to FindInsertedValue.

The only functional change is that newly created instructions are no longer
added to instcombine's worklist, but that is not really necessary anyway (and
I'll commit some improvements next that will completely remove the need).

llvm-svn: 52315
2008-06-16 12:48:21 +00:00
Chris Lattner 1c9922703f Fix the crash on SimplifyLibCalls/2005-05-20-sprintf-crash.ll
llvm-svn: 52295
2008-06-16 04:10:21 +00:00
Chris Lattner a88cd4ea2a Fix a case where tailcallelim wouldn't set the changed bit when it made a change.
llvm-svn: 52267
2008-06-14 00:49:48 +00:00
Eli Friedman 5de0a77a9b Don't skip over instructions other than loads that might read memory
when trying to sink stores.

llvm-svn: 52259
2008-06-13 22:02:12 +00:00
Dan Gohman 9ad8c54aab Protect ChangeCompareStride from situations in which it is possible
for it to generate use-before-def IR, such as in this testcase.

llvm-svn: 52258
2008-06-13 21:43:41 +00:00
Eli Friedman 9833a1b407 Make sure SimplifyStoreAtEndOfBlock doesn't mess with loops; the
structure checks are incorrect if the blocks aren't distinct.
Fixes PR2435.

llvm-svn: 52257
2008-06-13 21:17:49 +00:00
Wojciech Matyjewicz 25a7f5de92 Use recently added getTruncateOrZeroExtend method to make the code shorter.
llvm-svn: 52251
2008-06-13 17:02:03 +00:00
Gabor Greif 431e9560b7 fix a minor deviation from the original in my previous commit
llvm-svn: 52247
2008-06-12 21:51:29 +00:00
Gabor Greif f6d8e77027 op_iterator-ify some loops, low hanging fruit only, there is more
llvm-svn: 52246
2008-06-12 21:37:33 +00:00
Evan Cheng 89553cc42e Do not speculatively execute an instruction by hoisting it to its predecessor BB if any of its operands are defined but not used in BB. The transformation will prevent the operand from being sunk into the use block.
llvm-svn: 52244
2008-06-12 21:15:59 +00:00
Evan Cheng 70fe16353a Revert 52223.
llvm-svn: 52243
2008-06-12 20:55:39 +00:00
Owen Anderson accdca1b03 Switch GVN to use ScopedHashTable.
llvm-svn: 52242
2008-06-12 19:25:32 +00:00
Gabor Greif 0babc61631 op_iterator-ify some loops, fix 80col violations
llvm-svn: 52226
2008-06-11 21:38:51 +00:00
Evan Cheng 933c743042 For now, avoid generating FP select instructions in order to speculatively execute integer arithmetic instructions. FP selects are more likely to be expensive (even compared to branch on fcmp). This is not a wonderful solution but I rather err on the side of conservative.
This fixes the heapsort performance regressions.

llvm-svn: 52224
2008-06-11 19:18:20 +00:00
Evan Cheng f3c2902ead Avoid duplicating loop header which leads to unnatural loops (and just seem like general badness to me, likely to cause code explosion).
Patch by Florian Brandner.

llvm-svn: 52223
2008-06-11 19:07:54 +00:00
Matthijs Kooijman b2fc72bfbf Teach instruction combining about the extractvalue. It can succesfully fold
useless insert-extract chains, similar to how it folds them for vectors.

Add a testcase for this.

llvm-svn: 52217
2008-06-11 14:05:05 +00:00
Matthijs Kooijman 3453c7bcb5 Clarify a comment.
llvm-svn: 52212
2008-06-11 09:00:12 +00:00
Gabor Greif 945f2f7fed op_iterator-ify loops
llvm-svn: 52191
2008-06-10 22:03:26 +00:00
Chris Lattner 9c9f531a47 lower calls to abs to inline code, PR2337
llvm-svn: 52138
2008-06-09 08:26:51 +00:00
Chris Lattner dbd595f22d Fix PR2411, where ip constant prop would propagate the
result of a weak function.

llvm-svn: 52137
2008-06-09 07:58:07 +00:00
Duncan Sands 11dd424539 Remove comparison methods for MVT. The main cause
of apint codegen failure is the DAG combiner doing
the wrong thing because it was comparing MVT's using
< rather than comparing the number of bits.  Removing
the < method makes this mistake impossible to commit.
Instead, add helper methods for comparing bits and use
them.

llvm-svn: 52098
2008-06-08 20:54:56 +00:00
Chris Lattner b4866ef30c Limit the icmp+phi merging optimization to the cases where it is profitable:
don't make i1 phis when it won't be possible to eliminate them.

llvm-svn: 52097
2008-06-08 20:52:11 +00:00
Evan Cheng 89200c9177 Speculatively execute a block when the the block is the then part of a triangle shape and it contains a single, side effect free, cheap instruction. The branch is eliminated by adding a select instruction. i.e.
Turn                                                                                                                                                                                                       
BB:                                                                                                                                                                                                        
    %t1 = icmp                                                                                                                                                                                             
    br i1 %t1, label %BB1, label %BB2                                                                                                                                                                      
BB1:                                                                                                                                                                                                       
    %t3 = add %t2, c                                                                                                                                                                                       
    br label BB2                                                                                                                                                                                           
BB2:                                                                                                                                                                                                       
=>                                                                                                                                                                                                         
BB:                                                                                                                                                                                                        
    %t1 = icmp                                                                                                                                                                                             
    %t4 = add %t2, c                                                                                                                                                                                       
    %t3 = select i1 %t1, %t2, %t3

llvm-svn: 52073
2008-06-07 08:52:29 +00:00
Devang Patel 8549e4ca07 LoopSimplify preserves AA.
llvm-svn: 52053
2008-06-06 17:50:58 +00:00
Duncan Sands 13237ac3b9 Wrap MVT::ValueType in a struct to get type safety
and better control the abstraction.  Rename the type
to MVT.  To update out-of-tree patches, the main
thing to do is to rename MVT::ValueType to MVT, and
rewrite expressions like MVT::getSizeInBits(VT) in
the form VT.getSizeInBits().  Use VT.getSimpleVT()
to extract a MVT::SimpleValueType for use in switch
statements (you will get an assert failure if VT is
an extended value type - these shouldn't exist after
type legalization).
This results in a small speedup of codegen and no
new testsuite failures (x86-64 linux).

llvm-svn: 52044
2008-06-06 12:08:01 +00:00