Commit Graph

2424 Commits

Author SHA1 Message Date
Owen Anderson
7b6fafaa8d We should be returning true here since we've changed the function.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@50442 91177308-0d34-0410-b5e6-96231b3b80d8
2008-04-29 21:02:46 +00:00
Owen Anderson
9862f31533 A lot of cleanups and documentation improvements, as well as a few corner case fixes. Most
of this was suggested by Chris.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@50441 91177308-0d34-0410-b5e6-96231b3b80d8
2008-04-29 20:59:33 +00:00
Owen Anderson
0396cd33ca Rename DeadLoopElimination to LoopDeletion, part 2.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@50437 91177308-0d34-0410-b5e6-96231b3b80d8
2008-04-29 20:06:54 +00:00
Owen Anderson
d6864fee97 Rename DeadLoopElimination to LoopDeletion, part one.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@50436 91177308-0d34-0410-b5e6-96231b3b80d8
2008-04-29 19:58:07 +00:00
Chris Lattner
40700fe683 don't eliminate load from volatile value on paths where the load is dead.
This fixes the second half of PR2262


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@50430 91177308-0d34-0410-b5e6-96231b3b80d8
2008-04-29 17:28:22 +00:00
Chris Lattner
54545ac023 fix a subtle volatile handling bug.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@50428 91177308-0d34-0410-b5e6-96231b3b80d8
2008-04-29 17:13:43 +00:00
Owen Anderson
5f8b344255 Clarify what we mean by a dead loop.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@50406 91177308-0d34-0410-b5e6-96231b3b80d8
2008-04-29 06:34:55 +00:00
Chris Lattner
cea1fdd174 don't delete the last store to an alloca if the store is volatile.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@50390 91177308-0d34-0410-b5e6-96231b3b80d8
2008-04-29 04:58:38 +00:00
Owen Anderson
e54cfdb32a Add some more comments.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@50384 91177308-0d34-0410-b5e6-96231b3b80d8
2008-04-29 00:45:15 +00:00
Owen Anderson
d3d5b888d9 Remove debugging code.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@50383 91177308-0d34-0410-b5e6-96231b3b80d8
2008-04-29 00:39:24 +00:00
Owen Anderson
0ff7708a5b Add dead loop elimination, which removes dead loops for which we can compute
the trip count.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@50382 91177308-0d34-0410-b5e6-96231b3b80d8
2008-04-29 00:38:34 +00:00
Dan Gohman
00acf97feb Fix DSE to not eliminate volatile loads with no uses.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@50370 91177308-0d34-0410-b5e6-96231b3b80d8
2008-04-28 19:51:27 +00:00
Dan Gohman
23e8b71526 Teach InstCombine's ComputeMaskedBits what SelectionDAG's
ComputeMaskedBits knows about cttz, ctlz, and ctpop. Teach
SelectionDAG's ComputeMaskedBits what InstCombine's knows
about SRem. And teach them both some things about high bits
in Mul, UDiv, URem, and Sub. This allows instcombine and
dagcombine to eliminate sign-extension operations in
several new cases.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@50358 91177308-0d34-0410-b5e6-96231b3b80d8
2008-04-28 17:02:21 +00:00
Chris Lattner
5a09690446 Implement a signficant optimization for inline asm:
When choosing between constraints with multiple options,
like "ir", test to see if we can use the 'i' constraint and
go with that if possible.  This produces more optimal ASM in
all cases (sparing a register and an instruction to load it),
and fixes inline asm like this:

void test () {
  asm volatile (" %c0 %1 " : : "imr" (42), "imr"(14));
}

Previously we would dump "42" into a memory location (which
is ok for the 'm' constraint) which would cause a problem
because the 'c' modifier is not valid on memory operands.

Isn't it great how inline asm turns 'missed optimization'
into 'compile failed'??

Incidentally, this was the todo in 
PowerPC/2007-04-24-InlineAsm-I-Modifier.ll

Please do NOT pull this into Tak.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@50315 91177308-0d34-0410-b5e6-96231b3b80d8
2008-04-27 00:37:18 +00:00
Chris Lattner
4376fea663 Move a bunch of inline asm code out of line.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@50313 91177308-0d34-0410-b5e6-96231b3b80d8
2008-04-27 00:09:47 +00:00
Dale Johannesen
da30ccbe9a change comments per review
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@50300 91177308-0d34-0410-b5e6-96231b3b80d8
2008-04-25 21:16:07 +00:00
Dan Gohman
23ce502cb7 Remove the code from CodeGenPrepare that moved getresult instructions
to the block that defines their operands. This doesn't work in the
case that the operand is an invoke, because invoke is a terminator
and must be the last instruction in a block.

Replace it with support in SelectionDAGISel for copying struct values
into sequences of virtual registers.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@50279 91177308-0d34-0410-b5e6-96231b3b80d8
2008-04-25 18:27:55 +00:00
Nick Lewycky
280a6e607d Remove 'unwinds to' support from mainline. This patch undoes r47802 r47989
r48047 r48084 r48085 r48086 r48088 r48096 r48099 r48109 and r48123.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@50265 91177308-0d34-0410-b5e6-96231b3b80d8
2008-04-25 16:53:59 +00:00
Chris Lattner
eede65ce6c Don't infininitely thread branches when a threaded edge
goes back to the block, e.g.:

  Threading edge through bool from 'bb37.us.thread3829' to 'bb37.us' with cost: 1, across block:

bb37.us:		; preds = %bb37.us.thread3829, %bb37.us, %bb33
	%D1361.1.us = phi i32 [ %tmp36, %bb33 ], [ %D1361.1.us, %bb37.us ], [ 0, %bb37.us.thread3829 ]		; <i32> [#uses=2]
	%tmp39.us = icmp eq i32 %D1361.1.us, 0		; <i1> [#uses=1]
	br i1 %tmp39.us, label %bb37.us, label %bb42.us



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@50251 91177308-0d34-0410-b5e6-96231b3b80d8
2008-04-25 04:12:29 +00:00
Chris Lattner
eb5f4092d9 code restructuring, not functionality change.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@50203 91177308-0d34-0410-b5e6-96231b3b80d8
2008-04-24 00:21:50 +00:00
Chris Lattner
7cb22ecf22 Don't replace multiple result of calls with undef,
sccp tracks getresult values, not call values in this
case.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@50202 91177308-0d34-0410-b5e6-96231b3b80d8
2008-04-24 00:19:54 +00:00
Chris Lattner
f4023a1ef6 code cleanup, no functionality change.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@50201 91177308-0d34-0410-b5e6-96231b3b80d8
2008-04-24 00:16:28 +00:00
Dale Johannesen
1f530a59f7 Rewrite previous patch to suit Chris's preference.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@50174 91177308-0d34-0410-b5e6-96231b3b80d8
2008-04-23 18:34:37 +00:00
Chris Lattner
c6ee00b8ee Rewrite multiple return value handling in SCCP. Before, the -sccp pass
would turn every getresult instruction into undef.  This helps with
rdar://5778210


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@50140 91177308-0d34-0410-b5e6-96231b3b80d8
2008-04-23 05:38:20 +00:00
Dale Johannesen
63e7eb4e12 Do not change the type of a ByVal argument to a
type of a different size.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@50121 91177308-0d34-0410-b5e6-96231b3b80d8
2008-04-23 01:03:05 +00:00
Evan Cheng
f30752cbcc Don't do: "(X & 4) >> 1 == 2 --> (X & 4) == 4" if there are more than one uses of the shift result.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@50118 91177308-0d34-0410-b5e6-96231b3b80d8
2008-04-23 00:38:06 +00:00
Chris Lattner
a5ddb59a13 Start doing the significantly useful part of jump threading: handle cases
where a comparison has a phi input and that phi is a constant.  For example,
stuff like:

  Threading edge through bool from 'bb2149' to 'bb2231' with cost: 1, across block:
bb2237:		; preds = %bb2231, %bb2149
	%tmp2328.rle = phi i32 [ %tmp2232, %bb2231 ], [ %tmp2232439, %bb2149 ]		; <i32> [#uses=2]
	%done.0 = phi i32 [ %done.2, %bb2231 ], [ 0, %bb2149 ]		; <i32> [#uses=1]
	%tmp2239 = icmp eq i32 %done.0, 0		; <i1> [#uses=1]
	br i1 %tmp2239, label %bb2231, label %bb2327

or

bb38.i298:		; preds = %bb33.i295, %bb1693
	%tmp39.i296.rle = phi %struct.ibox* [ null, %bb1693 ], [ %tmp39.i296.rle1109, %bb33.i295 ]		; <%struct.ibox*> [#uses=2]
	%minspan.1.i291.reg2mem.1 = phi i32 [ 32000, %bb1693 ], [ %minspan.0.i288, %bb33.i295 ]		; <i32> [#uses=1]
	%tmp40.i297 = icmp eq %struct.ibox* %tmp39.i296.rle, null		; <i1> [#uses=1]
	br i1 %tmp40.i297, label %implfeeds.exit311, label %bb43.i301

This triggers thousands of times in spec.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@50110 91177308-0d34-0410-b5e6-96231b3b80d8
2008-04-22 21:40:39 +00:00
Chris Lattner
ae65b3c791 Dig through multiple levels of AND to thread jumps if needed.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@50106 91177308-0d34-0410-b5e6-96231b3b80d8
2008-04-22 20:46:09 +00:00
Chris Lattner
6bf77500c6 Teach jump threading to thread through blocks like:
br (and X, phi(Y, Z, false)), label L1, label L2

This triggers once on 252.eon and 6 times on 176.gcc.  Blocks 
in question often look like this:

bb262:		; preds = %bb261, %bb248
	%iftmp.251.0 = phi i1 [ true, %bb261 ], [ false, %bb248 ]		; <i1> [#uses=4]
	%tmp270 = icmp eq %struct.rtx_def* %tmp.0.i, null		; <i1> [#uses=1]
	%bothcond = or i1 %iftmp.251.0, %tmp270		; <i1> [#uses=1]
	br i1 %bothcond, label %bb288, label %bb273

In this case, it is clear that it doesn't matter if tmp.0.i is null when coming from bb261.  When coming from bb248, it is all that matters.


Another random example:

check_asm_operands.exit:		; preds = %check_asm_operands.exit.thr_comm, %bb30.i, %bb12.i, %bb6.i413
	%tmp.0.i420 = phi i1 [ true, %bb6.i413 ], [ true, %bb12.i ], [ true, %bb30.i ], [ false, %check_asm_operands.exit.thr_comm ; <i1> [#uses=1]
	call void @llvm.stackrestore( i8* %savedstack ) nounwind 
	%tmp4389 = icmp eq i32 %added_sets_1.0, 0		; <i1> [#uses=1]
	%tmp4394 = icmp eq i32 %added_sets_2.0, 0		; <i1> [#uses=1]
	%bothcond80 = and i1 %tmp4389, %tmp4394		; <i1> [#uses=1]
	%bothcond81 = and i1 %bothcond80, %tmp.0.i420		; <i1> [#uses=1]
	br i1 %bothcond81, label %bb4398, label %bb4397

Here is the case from 252.eon:

bb290.i.i:		; preds = %bb23.i57.i.i, %bb8.i39.i.i, %bb100.i.i, %bb100.i.i, %bb85.i.i110
	%myEOF.1.i.i = phi i1 [ true, %bb100.i.i ], [ true, %bb100.i.i ], [ true, %bb85.i.i110 ], [ true, %bb8.i39.i.i ], [ false, %bb23.i57.i.i ]		; <i1> [#uses=2]
	%i.4.i.i = phi i32 [ %i.1.i.i, %bb85.i.i110 ], [ %i.0.i.i, %bb100.i.i ], [ %i.0.i.i, %bb100.i.i ], [ %i.3.i.i, %bb8.i39.i.i ], [ %i.3.i.i, %bb23.i57.i.i ]		; <i32> [#uses=3]
	%tmp292.i.i = load i8* %tmp16.i.i100, align 1		; <i8> [#uses=1]
	%tmp293.not.i.i = icmp ne i8 %tmp292.i.i, 0		; <i1> [#uses=1]
	%bothcond.i.i = and i1 %tmp293.not.i.i, %myEOF.1.i.i		; <i1> [#uses=1]
	br i1 %bothcond.i.i, label %bb202.i.i, label %bb301.i.i
  Factoring out 3 common predecessors.

On the path from any blocks other than bb23.i57.i.i, the load and compare 
are dead.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@50096 91177308-0d34-0410-b5e6-96231b3b80d8
2008-04-22 07:05:46 +00:00
Chris Lattner
d38c14e6ed refactor some code, no functionality change.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@50094 91177308-0d34-0410-b5e6-96231b3b80d8
2008-04-22 06:36:15 +00:00
Chris Lattner
9d4b94d3e1 remove dead code.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@50080 91177308-0d34-0410-b5e6-96231b3b80d8
2008-04-22 03:21:48 +00:00
Chris Lattner
10c0d9179e optimize "p != gep p, ..." better. This allows us to compile
getelementptr-seteq.ll into:

define i1 @test(i64 %X, %S* %P) {
	%C = icmp eq i64 %X, -1		; <i1> [#uses=1]
	ret i1 %C
}

instead of:

define i1 @test(i64 %X, %S* %P) {
	%A.idx.mask = and i64 %X, 4611686018427387903		; <i64> [#uses=1]
	%C = icmp eq i64 %A.idx.mask, 4611686018427387903		; <i1> [#uses=1]
	ret i1 %C
}

And fixes the second half of PR2235.  This speeds up the insertion sort
case by 45%, from 1.12s to 0.77s.  In practice, this will significantly
speed up for loops structured like:

for (double *P = Base + N; P != Base; --P)
  ...

Which happens frequently for C++ iterators.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@50079 91177308-0d34-0410-b5e6-96231b3b80d8
2008-04-22 02:53:33 +00:00
Chris Lattner
037c781de7 fix grammar-o, thanks to Duncan for noticing.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@50047 91177308-0d34-0410-b5e6-96231b3b80d8
2008-04-21 18:25:01 +00:00
Owen Anderson
4bda6e47e9 Remove unneeded #include's.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@50035 91177308-0d34-0410-b5e6-96231b3b80d8
2008-04-21 07:47:38 +00:00
Owen Anderson
a8bd65835b Refactor memcpyopt based on Chris' suggestions. Consolidate several functions
and simplify code that was fallout from the separation of memcpyopt and gvn.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@50034 91177308-0d34-0410-b5e6-96231b3b80d8
2008-04-21 07:45:10 +00:00
Chris Lattner
2cc675180b Use the new SplitBlockPredecessors to implement a todo.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@50022 91177308-0d34-0410-b5e6-96231b3b80d8
2008-04-21 02:57:57 +00:00
Chris Lattner
48a80b07bd fit some more code in 80 cols.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@50016 91177308-0d34-0410-b5e6-96231b3b80d8
2008-04-21 00:25:49 +00:00
Chris Lattner
bd3401fa98 finish the first cut of a jump threading pass implementation.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@50006 91177308-0d34-0410-b5e6-96231b3b80d8
2008-04-20 22:39:42 +00:00
Chris Lattner
0cfe85be0b replace a slow and verbose version of Instruction::isUsedOutsideOfBlock with
a call to Instruction::isUsedOutsideOfBlock.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@50005 91177308-0d34-0410-b5e6-96231b3b80d8
2008-04-20 22:18:22 +00:00
Chris Lattner
f9065a904f we can only thread blocks when there is a pred we can determine the succ of.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@50003 91177308-0d34-0410-b5e6-96231b3b80d8
2008-04-20 21:18:09 +00:00
Chris Lattner
177480b7ed improve comments, infrastructure, and add some validity checks for threading.
Add a cost function.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@50002 91177308-0d34-0410-b5e6-96231b3b80d8
2008-04-20 21:13:06 +00:00
Chris Lattner
8383a7b7a6 Add a new Jump Threading pass, which will handle cases
such as those in PR2235.  Right now the pass is not very
effective. :)


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@50000 91177308-0d34-0410-b5e6-96231b3b80d8
2008-04-20 20:35:01 +00:00
Torok Edwin
3eaee31393 g++-4.3 build-fix: CHAR_BIT requires <climits>.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@49989 91177308-0d34-0410-b5e6-96231b3b80d8
2008-04-20 08:33:11 +00:00
Chris Lattner
02a260aa11 Switch to using Simplified ConstantFP::get API.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@49977 91177308-0d34-0410-b5e6-96231b3b80d8
2008-04-20 00:41:09 +00:00
Owen Anderson
241f65321e Make GVN able to remove unnecessary calls to read-only functions again.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@49842 91177308-0d34-0410-b5e6-96231b3b80d8
2008-04-17 05:36:50 +00:00
Dan Gohman
0a9371de6d Remove unnecessary <sstream> includes.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@49681 91177308-0d34-0410-b5e6-96231b3b80d8
2008-04-14 20:40:47 +00:00
Dan Gohman
4a9a3e5374 Minor whitespace and comment cleanups.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@49671 91177308-0d34-0410-b5e6-96231b3b80d8
2008-04-14 18:26:16 +00:00
Owen Anderson
6bc41e8a74 Revert r49614. As Dan pointed out, some of these aren't correct.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@49657 91177308-0d34-0410-b5e6-96231b3b80d8
2008-04-14 17:38:21 +00:00
Owen Anderson
386ea355e7 Replace calls of the form V1->setName(V2->getName()) with V1->takeName(V2),
which is significantly more efficient.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@49614 91177308-0d34-0410-b5e6-96231b3b80d8
2008-04-13 19:15:17 +00:00
Owen Anderson
8f46c78fcc Fix PR2213 by simultaneously making GVN more aggressive with the return values
of calls and less aggressive with non-readnone calls.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@49516 91177308-0d34-0410-b5e6-96231b3b80d8
2008-04-11 05:11:49 +00:00
Dan Gohman
eee962e1ce Teach InstCombine's ComputeMaskedBits to handle pointer expressions
in addition to integer expressions. Rewrite GetOrEnforceKnownAlignment
as a ComputeMaskedBits problem, moving all of its special alignment
knowledge to ComputeMaskedBits as low-zero-bits knowledge.

Also, teach ComputeMaskedBits a few basic things about Mul and PHI
instructions.

This improves ComputeMaskedBits-based simplifications in a few cases,
but more noticeably it significantly improves instcombine's alignment
detection for loads, stores, and memory intrinsics.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@49492 91177308-0d34-0410-b5e6-96231b3b80d8
2008-04-10 18:43:06 +00:00
Devang Patel
d4e0af9f89 Be conservative if getresult operand is neither call nor invoke.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@49430 91177308-0d34-0410-b5e6-96231b3b80d8
2008-04-09 15:58:24 +00:00
Owen Anderson
a723d1e48f Factor a bunch of functionality related to memcpy and memset transforms out of
GVN and into its own pass.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@49419 91177308-0d34-0410-b5e6-96231b3b80d8
2008-04-09 08:23:16 +00:00
Owen Anderson
82a66291b0 Remove accidentally duplicated code.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@49418 91177308-0d34-0410-b5e6-96231b3b80d8
2008-04-09 07:55:01 +00:00
Owen Anderson
412821284f Add operator= implementations to SparseBitVector, allowing it to be used in GVN. This results
in both time and memory savings for GVN.  For example, one testcase went from 10.5s to 6s with
this patch.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@49345 91177308-0d34-0410-b5e6-96231b3b80d8
2008-04-07 17:38:23 +00:00
Owen Anderson
e5ffa900f8 Make GVN more memory efficient, particularly on code that contains a large number of
allocations, which GVN can't optimize anyways.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@49329 91177308-0d34-0410-b5e6-96231b3b80d8
2008-04-07 09:59:07 +00:00
Chris Lattner
0c80c75783 silence a warning when assertions are disabled.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@49283 91177308-0d34-0410-b5e6-96231b3b80d8
2008-04-06 21:44:08 +00:00
Gabor Greif
051a950000 API changes for class Use size reduction, wave 1.
Specifically, introduction of XXX::Create methods
for Users that have a potentially variable number of
Uses.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@49277 91177308-0d34-0410-b5e6-96231b3b80d8
2008-04-06 20:25:17 +00:00
David Greene
a022e3fc2f Iterators folloring a SmallVector erased element are invalidated so
don't access cached iterators from after the erased element.

Re-apply 49056 with SmallVector support.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@49106 91177308-0d34-0410-b5e6-96231b3b80d8
2008-04-02 18:24:46 +00:00
Tanya Lattner
48afd9f8a9 Reverting 49056 due to the build being broken.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@49060 91177308-0d34-0410-b5e6-96231b3b80d8
2008-04-01 23:41:44 +00:00
David Greene
da2903f028 Iterators folloring a SmallVector erased element are invalidated so
don't access cached iterators from after the erased element.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@49056 91177308-0d34-0410-b5e6-96231b3b80d8
2008-04-01 22:14:23 +00:00
Nate Begeman
83ad90a779 Don't eliminate bitcast instructions that change the type of a pointer
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@48971 91177308-0d34-0410-b5e6-96231b3b80d8
2008-03-31 00:22:16 +00:00
Chris Lattner
d27c991ceb Fix "Control reaches the end of non-void function" warnings,
patch by David Chisnall.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@48963 91177308-0d34-0410-b5e6-96231b3b80d8
2008-03-30 18:22:13 +00:00
Chris Lattner
97ae12a988 change iterator invalidation avoidance to just move the iterator backward
when something changes, instead of moving forward.  This allows us to 
simplify memset lowering, inserting the memset at the end of the range of 
stuff we're touching instead of at the start.

This, in turn, allows us to make use of the addressing instructions already
used in the function instead of inserting our own.  For example, we now
codegen:

	%tmp41 = getelementptr [8 x i8]* %ref_idx, i32 0, i32 0		; <i8*> [#uses=2]
	call void @llvm.memset.i64( i8* %tmp41, i8 -1, i64 8, i32 1 )

instead of:

	%tmp20 = getelementptr [8 x i8]* %ref_idx, i32 0, i32 7		; <i8*> [#uses=1]
	%ptroffset = getelementptr i8* %tmp20, i64 -7		; <i8*> [#uses=1]
	call void @llvm.memset.i64( i8* %ptroffset, i8 -1, i64 8, i32 1 )



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@48940 91177308-0d34-0410-b5e6-96231b3b80d8
2008-03-29 05:15:47 +00:00
Chris Lattner
d22fe2b51f make the common case of a single store (which clearly shouldn't be turned
into a memset!) faster by avoiding an allocation of an std::list node.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@48939 91177308-0d34-0410-b5e6-96231b3b80d8
2008-03-29 04:52:12 +00:00
Chris Lattner
9f8a6a7498 give form-memset a significantly more sane heuristic, enable it by default.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@48937 91177308-0d34-0410-b5e6-96231b3b80d8
2008-03-29 04:36:18 +00:00
Chris Lattner
7f0965e7da make memset inference significantly more powerful: it can now handle
memsets that initialize "structs of arrays" and other store sequences
that are not sequential.  This is still only enabled if you pass 
-form-memset-from-stores.  The flag is not heavily tested and I haven't
analyzed the perf regressions when -form-memset-from-stores is passed
either, but this causes no make check regressions.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@48909 91177308-0d34-0410-b5e6-96231b3b80d8
2008-03-28 06:45:13 +00:00
Devang Patel
4a3c0ac798 PHI->removeIncomingValue may remove PHInode.
Increment iterator in advance.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@48890 91177308-0d34-0410-b5e6-96231b3b80d8
2008-03-27 17:32:46 +00:00
Evan Cheng
d34af7875b Handle a special case xor undef, undef -> 0. Technically this should be transformed to undef. But this is such a common idiom (misuse) we are going to handle it.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@48791 91177308-0d34-0410-b5e6-96231b3b80d8
2008-03-25 20:07:13 +00:00
Devang Patel
60a12907c3 Add incoming value from header only if phi node has any use inside the loop.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@48738 91177308-0d34-0410-b5e6-96231b3b80d8
2008-03-24 20:16:14 +00:00
Evan Cheng
88ffdddcc4 Temporarily disabling memset forming optimization. Add an option.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@48720 91177308-0d34-0410-b5e6-96231b3b80d8
2008-03-24 05:28:38 +00:00
Evan Cheng
b98a10e8a3 Transform (zext (or (icmp), (icmp))) to (or (zext (cimp), (zext icmp))) if at least one of the (zext icmp) can be transformed to eliminate an icmp.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@48715 91177308-0d34-0410-b5e6-96231b3b80d8
2008-03-24 00:21:34 +00:00
Chris Lattner
b017c9e89c implement an initial hack at a straight-line store -> memset optimization.
This fires dozens of times across spec and multisource, but I don't know
if it actually speeds stuff up.  Hopefully the testers will show something
nice :)



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@48680 91177308-0d34-0410-b5e6-96231b3b80d8
2008-03-22 05:37:16 +00:00
Chris Lattner
d27290d733 implement the logic for memset insertion and store deletion.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@48679 91177308-0d34-0410-b5e6-96231b3b80d8
2008-03-22 04:13:49 +00:00
Chris Lattner
641dae19eb This is a partially implemented and currently disabled start of a store
merging optimization.  Nothing to see here, hopefully more later :)


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@48670 91177308-0d34-0410-b5e6-96231b3b80d8
2008-03-22 00:31:52 +00:00
Dan Gohman
c9235d2e85 Don't include <map> in Pass.h, which doesn't need it. This requires
adding <map> to many files that actually do need it.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@48667 91177308-0d34-0410-b5e6-96231b3b80d8
2008-03-21 23:51:57 +00:00
Chris Lattner
8e1e95cb04 the size of a smallvector shouldn't be part of the interface to these methods.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@48662 91177308-0d34-0410-b5e6-96231b3b80d8
2008-03-21 22:01:16 +00:00
Chris Lattner
2e60701b9d make gvn marginally faster by reallocating the lastSeenLoad map for
each basic block.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@48660 91177308-0d34-0410-b5e6-96231b3b80d8
2008-03-21 21:33:23 +00:00
Chris Lattner
88365bb404 Minor cleanups and shrinkification.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@48658 91177308-0d34-0410-b5e6-96231b3b80d8
2008-03-21 21:14:38 +00:00
Dan Gohman
f1d3d666c1 Handle getresult instructions in different basic blocks
from their aggregate operands by moving the getresult
instructions.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@48657 91177308-0d34-0410-b5e6-96231b3b80d8
2008-03-21 21:01:32 +00:00
Duncan Sands
1d57a752a2 Fix the build for gcc-4.2.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@48639 91177308-0d34-0410-b5e6-96231b3b80d8
2008-03-21 08:32:17 +00:00
Chris Lattner
41dc0fcb68 Teach masked value is zero about add and sub, and use MVIZ to
simplify things like (X & 4) >> 1 == 2  --> (X & 4) == 4.

since it is obvious that the shift doesn't remove any bits.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@48631 91177308-0d34-0410-b5e6-96231b3b80d8
2008-03-21 05:19:58 +00:00
Gordon Henriksen
69cf031ee3 C and Objective Caml bindings for mem2reg and reg2mem.
Patch by Erick Tryzelaar.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@48602 91177308-0d34-0410-b5e6-96231b3b80d8
2008-03-20 17:16:03 +00:00
Devang Patel
ac3844d3f9 Add comment.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@48567 91177308-0d34-0410-b5e6-96231b3b80d8
2008-03-19 23:05:52 +00:00
Evan Cheng
55e641b766 Remove dead options.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@48556 91177308-0d34-0410-b5e6-96231b3b80d8
2008-03-19 22:02:26 +00:00
Devang Patel
b176038f98 Update heuritics that estimates cost of call instructions.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@48474 91177308-0d34-0410-b5e6-96231b3b80d8
2008-03-17 23:41:20 +00:00
Gordon Henriksen
41ba1546eb C and Objective Caml bindings for several scalar transforms.
Patch originally by Erick Tryzelaar, but has been modified somewhat.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@48419 91177308-0d34-0410-b5e6-96231b3b80d8
2008-03-16 16:32:40 +00:00
Bill Wendling
b9d4f8df70 The inst combining of inttoptr into GEP with one index was using the bit size of
the type instead of the byte size. This was causing troublesome mis-compilations.

True to form, this took 2 days to find and is a one-line fix. :-P


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@48354 91177308-0d34-0410-b5e6-96231b3b80d8
2008-03-14 05:12:19 +00:00
Owen Anderson
8a97fddbc2 Fix a bug in GVN that Duncan noticed, where we potentially need to insert a
pointer bitcast when performing return slot optimization.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@48343 91177308-0d34-0410-b5e6-96231b3b80d8
2008-03-13 22:07:10 +00:00
Chris Lattner
58d74910c6 Reimplement the parameter attributes support, phase #1. hilights:
1. There is now a "PAListPtr" class, which is a smart pointer around
   the underlying uniqued parameter attribute list object, and manages
   its refcount.  It is now impossible to mess up the refcount.
2. PAListPtr is now the main interface to the underlying object, and
   the underlying object is now completely opaque.
3. Implementation details like SmallVector and FoldingSet are now no
   longer part of the interface.
4. You can create a PAListPtr with an arbitrary sequence of
   ParamAttrsWithIndex's, no need to make a SmallVector of a specific 
   size (you can just use an array or scalar or vector if you wish).
5. All the client code that had to check for a null pointer before
   dereferencing the pointer is simplified to just access the 
   PAListPtr directly.
6. The interfaces for adding attrs to a list and removing them is a
   bit simpler.

Phase #2 will rename some stuff (e.g. PAListPtr) and do other less 
invasive changes.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@48289 91177308-0d34-0410-b5e6-96231b3b80d8
2008-03-12 17:45:29 +00:00
Owen Anderson
6bb0bd52ec Improve the return slot optimization to be both more aggressive (not limited to sret parameters), and
safer (when the passed pointer might be invalid).  Thanks to Duncan and Chris for the idea behind this, 
and extra thanks to Duncan for helping me work out the trap-safety.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@48280 91177308-0d34-0410-b5e6-96231b3b80d8
2008-03-12 07:37:44 +00:00
Devang Patel
75e6f02445 Skip functions that return multiple values.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@48233 91177308-0d34-0410-b5e6-96231b3b80d8
2008-03-11 18:04:06 +00:00
Devang Patel
826c49132a Become multiple return value aware.
Right now, the pass does not optimize tail recursions 
involving multiple return values.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@48228 91177308-0d34-0410-b5e6-96231b3b80d8
2008-03-11 17:33:32 +00:00
Devang Patel
9af014f80c Add TODO reminder.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@48227 91177308-0d34-0410-b5e6-96231b3b80d8
2008-03-11 17:32:05 +00:00
Devang Patel
7c490d4104 Initial multiple return values support.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@48210 91177308-0d34-0410-b5e6-96231b3b80d8
2008-03-11 05:46:42 +00:00
Nick Lewycky
a66696ef0d SCCP also needs to be taught to follow unwind_to
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@48109 91177308-0d34-0410-b5e6-96231b3b80d8
2008-03-09 09:44:38 +00:00
Nick Lewycky
9143699260 Don't eliminate blocks that are only reachable by unwind_to.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@48106 91177308-0d34-0410-b5e6-96231b3b80d8
2008-03-09 08:50:23 +00:00
Nick Lewycky
529de8a457 Update the block cloner which fixes bugpoint on code using unwind_to (phew!)
and also update the cloning interface's major user, the loop optimizations.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@48088 91177308-0d34-0410-b5e6-96231b3b80d8
2008-03-09 05:24:34 +00:00
Nick Lewycky
6c36a0f9ee Not all users of a BB are Instructions any more.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@48047 91177308-0d34-0410-b5e6-96231b3b80d8
2008-03-08 07:48:41 +00:00
Nick Lewycky
c1a2a61201 Don't try to simplify urem and srem using arithmetic rules that don't work
under modulo (overflow). Fixes PR1933.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@47987 91177308-0d34-0410-b5e6-96231b3b80d8
2008-03-06 06:48:30 +00:00
Chris Lattner
9d34c4d678 fix a bug Anders ran into where scalarrepl would crash when promoting
a union containing a vector and an array whose elements were smaller than
the vector elements.  this means we need to compile the load of the 
array elements into an extract element plus a truncate.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@47752 91177308-0d34-0410-b5e6-96231b3b80d8
2008-02-29 07:12:06 +00:00
Chris Lattner
800de31776 Refactor some code out of ConvertUsesToScalar into their own methods, no
functionality change.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@47751 91177308-0d34-0410-b5e6-96231b3b80d8
2008-02-29 07:03:13 +00:00
Chris Lattner
5ebd93630b Folding or(fcmp,fcmp) only works if the operands of the fcmps are the same fp type.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@47750 91177308-0d34-0410-b5e6-96231b3b80d8
2008-02-29 06:09:11 +00:00
Owen Anderson
77db50f68f Fix an issue where GVN had the sizes of the two memcpy's reverse, resulting
in an invalid transformation.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@47639 91177308-0d34-0410-b5e6-96231b3b80d8
2008-02-26 23:06:17 +00:00
Gabor Greif
53bdbd7565 fix http://llvm.org/bugs/show_bug.cgi?id=2097
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@47615 91177308-0d34-0410-b5e6-96231b3b80d8
2008-02-26 19:13:21 +00:00
Eli Friedman
9ec8095485 Fix for pr2093: direct operands aren't necessarily addresses, so don't
try to simplify them.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@47610 91177308-0d34-0410-b5e6-96231b3b80d8
2008-02-26 18:37:49 +00:00
Bill Wendling
587c01d674 De-tabify.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@47599 91177308-0d34-0410-b5e6-96231b3b80d8
2008-02-26 10:53:30 +00:00
Evan Cheng
9bf12b5583 Fix PR2076. CodeGenPrepare now sinks address computation for inline asm memory
operands into inline asm block.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@47589 91177308-0d34-0410-b5e6-96231b3b80d8
2008-02-26 02:42:37 +00:00
Owen Anderson
c0808a7e1d Fix an issue where GVN was performing the return slot optimization when it was
not safe.  This is fixed by more aggressively checking that the return slot is
not used elsewhere in the function.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@47544 91177308-0d34-0410-b5e6-96231b3b80d8
2008-02-25 04:08:09 +00:00
Owen Anderson
0f7ea1ab10 Fix an issue where GVN would try to use an instruction before its definition when performing return slot optimization.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@47541 91177308-0d34-0410-b5e6-96231b3b80d8
2008-02-25 00:40:41 +00:00
Dale Johannesen
22c3979fca Split ParameterAttributes.h, putting the complicated
stuff into ParamAttrsList.h.  Per feedback from
ParamAttrs changes.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@47504 91177308-0d34-0410-b5e6-96231b3b80d8
2008-02-22 22:17:59 +00:00
Zhou Sheng
58d13af6f0 Fixed a typo.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@47478 91177308-0d34-0410-b5e6-96231b3b80d8
2008-02-22 10:00:35 +00:00
Dan Gohman
b5660dc822 Add explicit keywords.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@47382 91177308-0d34-0410-b5e6-96231b3b80d8
2008-02-20 16:44:09 +00:00
Anton Korobeynikov
4aefd6b7d4 Fix newly-introduced 4.3 warnings
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@47375 91177308-0d34-0410-b5e6-96231b3b80d8
2008-02-20 12:07:57 +00:00
Anton Korobeynikov
07e6e56f57 Make Transforms to be 4.3 warnings-clean
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@47371 91177308-0d34-0410-b5e6-96231b3b80d8
2008-02-20 11:26:25 +00:00
Anton Korobeynikov
ae9f3a3b7c Unbreak build with gcc 4.3: provide missed includes and silence most annoying warnings.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@47367 91177308-0d34-0410-b5e6-96231b3b80d8
2008-02-20 11:08:44 +00:00
Owen Anderson
61d30a821f When performing return slot optimization, remember to inform memdep when we're removing the memcpy.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@47364 91177308-0d34-0410-b5e6-96231b3b80d8
2008-02-20 08:23:02 +00:00
Dale Johannesen
0d51e7ec0d Expand ParameterAttributes to 32 bits (in preparation
for adding alignment info, not there yet).  Clean up
interfaces to reference ParameterAttributes consistently.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@47342 91177308-0d34-0410-b5e6-96231b3b80d8
2008-02-19 21:38:47 +00:00
Chris Lattner
15f166c7b6 remove the lower packed pass. It can never work and even the parts that
could work don't work fully.  This fixes PR1705.  Oh yeah, we don't have
packed types anymore either ;-)


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@47322 91177308-0d34-0410-b5e6-96231b3b80d8
2008-02-19 07:39:17 +00:00
Owen Anderson
967552e7ec Refactor this method a bit, and correct a test that was completely wrong but happened to work out anyways. :-)
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@47321 91177308-0d34-0410-b5e6-96231b3b80d8
2008-02-19 07:07:51 +00:00
Chris Lattner
e42ce73c37 isa+cast -> dyncast.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@47320 91177308-0d34-0410-b5e6-96231b3b80d8
2008-02-19 06:53:20 +00:00
Chris Lattner
0a76a621a4 simplify this code again, try 2 :)
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@47319 91177308-0d34-0410-b5e6-96231b3b80d8
2008-02-19 06:52:38 +00:00
Owen Anderson
9cffa9a6ed Fix a comment.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@47318 91177308-0d34-0410-b5e6-96231b3b80d8
2008-02-19 06:51:23 +00:00
Owen Anderson
61c24e96b1 Major improvements to yesterday's return slot optimization. Remove some unneccessary constraints,
and add some others that should have been in from the first place.  Document the whole thing better.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@47315 91177308-0d34-0410-b5e6-96231b3b80d8
2008-02-19 06:35:43 +00:00
Chris Lattner
50b2ca4c73 fdiv/frem of undef can produce undef, because the undef operand
can be a SNaN.  We could be more aggressive and turn this into 
unreachable, but that is less nice, and not really worth it.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@47313 91177308-0d34-0410-b5e6-96231b3b80d8
2008-02-19 06:12:18 +00:00
Owen Anderson
fa113f8155 Factor the profitability check for return slot optimization out into a static function.
At some point in the future, this check will become smarter.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@47310 91177308-0d34-0410-b5e6-96231b3b80d8
2008-02-19 03:27:34 +00:00
Owen Anderson
c0755a6f98 An sret parameter is required to be the first parameter, so there's no need to loop
over all the parameters of the callee looking for it.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@47309 91177308-0d34-0410-b5e6-96231b3b80d8
2008-02-19 03:15:29 +00:00
Owen Anderson
7acc0af95a Cleanup some of my patches from yesterday. Refactor the check for which xform
to apply to a memcpy into processInstruction.  Also, fix a bug in the check due to
missing braces.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@47307 91177308-0d34-0410-b5e6-96231b3b80d8
2008-02-19 03:09:45 +00:00
Owen Anderson
c2580ab9b0 Fix Transforms/GVN/memcpy.ll, which Chris broke in r47275 by reordering the branches. memcpy's are a kind of CallInst.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@47305 91177308-0d34-0410-b5e6-96231b3b80d8
2008-02-19 02:53:23 +00:00
Nick Lewycky
e0cfecf47d Correctly fold divide-by-constant, even when faced with overflow.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@47287 91177308-0d34-0410-b5e6-96231b3b80d8
2008-02-18 22:48:05 +00:00
Chris Lattner
e10c0b9d66 Transforming -A + -B --> -(A + B) isn't safe for FP, thanks
to Dale for noticing this!


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@47276 91177308-0d34-0410-b5e6-96231b3b80d8
2008-02-18 17:50:16 +00:00
Chris Lattner
913b19f6fc minor code simplification, no functionality change.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@47275 91177308-0d34-0410-b5e6-96231b3b80d8
2008-02-18 17:47:29 +00:00
Owen Anderson
5aa4f2a085 Add support to GVN for performing sret return slot optimization. This means that, if an sret function tail calls
another sret function, it should pass its own sret parameter to the tail callee, allowing it to fill in the correct
return value.  llvm-gcc does not emit this by default.  Instead, it allocates space in the caller for the sret of
the tail call and then uses memcpy to copy the result into the caller's sret parameter.  This optimization detects
and optimizes that case.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@47265 91177308-0d34-0410-b5e6-96231b3b80d8
2008-02-18 09:24:53 +00:00
Chris Lattner
bf1d8a7099 optimize away stackrestore calls that have no intervening alloca or call.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@47258 91177308-0d34-0410-b5e6-96231b3b80d8
2008-02-18 06:12:38 +00:00
Chris Lattner
d5b8d92b9f simplify some code, BreakUpSubtract always returns nonnull now.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@47251 91177308-0d34-0410-b5e6-96231b3b80d8
2008-02-18 02:18:25 +00:00
Chris Lattner
dd12f96c5e Fold (-x + -y) -> -(x+y) which promotes better association, fixing
the second half of PR2047


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2008-02-17 21:03:36 +00:00
Chris Lattner
5329bb22e9 fix pasto
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@47242 91177308-0d34-0410-b5e6-96231b3b80d8
2008-02-17 20:54:40 +00:00
Chris Lattner
0b0803ae15 Split up subtracts into add+negate if they have a reassociable use or operand
that is also a subtract.  This implements PR2047 and Transforms/Reassociate/subtest2.ll 


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@47241 91177308-0d34-0410-b5e6-96231b3b80d8
2008-02-17 20:51:26 +00:00
Chris Lattner
9bc5ed78c8 make the logic for breaking up subtracts more explicit, no
functionality change.


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2008-02-17 20:44:51 +00:00
Devang Patel
9d9b204d6a Fix PR2028
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@47150 91177308-0d34-0410-b5e6-96231b3b80d8
2008-02-15 01:24:49 +00:00
Devang Patel
9b03daa2a3 If loop header is also loop exiting block then OrigPN is incoming value for B loop header.
Fixes PR 2030.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@47141 91177308-0d34-0410-b5e6-96231b3b80d8
2008-02-14 23:18:47 +00:00
Chris Lattner
13daadbd25 simplify code, no functionality change.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@47116 91177308-0d34-0410-b5e6-96231b3b80d8
2008-02-14 07:39:01 +00:00
Nick Lewycky
95f0ba2703 Fix PR2032. Inform the alias analysis of changes to the underlying program.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@47111 91177308-0d34-0410-b5e6-96231b3b80d8
2008-02-14 07:11:24 +00:00
Devang Patel
ea06906559 A loop latch phi node may have uses inside loop, not just in loop header.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@47093 91177308-0d34-0410-b5e6-96231b3b80d8
2008-02-13 22:23:07 +00:00
Dan Gohman
7649127ec1 Rename APInt's isPositive to isNonNegative, to reflect what it
actually does.


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2008-02-13 22:09:18 +00:00
Devang Patel
23067dfeac While moving exit condition, do not drop loop latch on the floor.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@47089 91177308-0d34-0410-b5e6-96231b3b80d8
2008-02-13 22:06:36 +00:00
Devang Patel
02c4836f3d Keep track of exit value operand number when operands are swapped.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@47082 91177308-0d34-0410-b5e6-96231b3b80d8
2008-02-13 19:48:48 +00:00
Owen Anderson
30b4bd4d10 Re-apply the patch to improve the optimizations of memcpy's, with several
bugs fixed.  This now passes PPC bootstrap.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@47026 91177308-0d34-0410-b5e6-96231b3b80d8
2008-02-12 21:15:18 +00:00
Eli Friedman
b6c36e4058 Fix for bug 1996: optimize out loads of undef. This code basically just
checks for a malloc/alloca immediately followed by a load.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@47006 91177308-0d34-0410-b5e6-96231b3b80d8
2008-02-12 12:08:14 +00:00
Chris Lattner
916c954bf2 Fix scalarrepl to not 'miscompile' undefined code, part #2.
This fixes the store case, my previous patch just fixed the load
case.  rdar://5707076.


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2008-02-10 19:05:37 +00:00