Commit Graph

2312 Commits

Author SHA1 Message Date
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