Commit Graph

4039 Commits

Author SHA1 Message Date
Owen Anderson
5023aa58ca This condition got inverted accidentally.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@50473 91177308-0d34-0410-b5e6-96231b3b80d8
2008-04-30 07:16:33 +00:00
Chris Lattner
69ea9d2308 move lowering of llvm.memset -> store from simplify libcalls
to instcombine.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@50472 91177308-0d34-0410-b5e6-96231b3b80d8
2008-04-30 06:39:11 +00:00
Chris Lattner
ea8650cddf use string length computation to generalize several xforms.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@50464 91177308-0d34-0410-b5e6-96231b3b80d8
2008-04-30 03:07:53 +00:00
Owen Anderson
02e9988020 Revert r50441. The original code was correct. Add some more comments so that I don't make the same mistake in the future.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@50446 91177308-0d34-0410-b5e6-96231b3b80d8
2008-04-29 21:51:00 +00:00
Owen Anderson
9dcace3caf Fix a bug in memcpyopt where the memcpy-memcpy transform was never being applied because
we were checking for it in the wrong order.  This caused a miscompilation because the
return slot optimization assumes that the call it is dealing with is NOT a memcpy.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@50444 91177308-0d34-0410-b5e6-96231b3b80d8
2008-04-29 21:26:06 +00:00
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
Chris Lattner
5b222d748a Implement more aggressive support for analyzing string length. This
generalizes the previous code to handle the case when the string is not
an immediate to the strlen call (for example, crazy stuff like 
strlen(c ? "foo" : "bart"+1) -> 3).  This implements 
gcc.c-torture/execute/builtins/strlen-2.c.  I will generalize other
cases in simplifylibcalls to use the same routine later.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@50408 91177308-0d34-0410-b5e6-96231b3b80d8
2008-04-29 06:56:02 +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
ffba5821ee Fix PR2256, yet another miscompilation in simplifycfg of i
multiple return values.

Bill, please pull this into Tak.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@50332 91177308-0d34-0410-b5e6-96231b3b80d8
2008-04-28 00:19:07 +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
Chris Lattner
998182b380 When SRoA'ing a global variable, make sure the new globals get the
appropriate alignment.  This fixes a miscompilation of 252.eon on
x86-64 (rdar://5891920).

Bill, please pull this into Tak.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@50308 91177308-0d34-0410-b5e6-96231b3b80d8
2008-04-26 07:40:11 +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
Nate Begeman
4182db4327 Feedback from chris
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@50271 91177308-0d34-0410-b5e6-96231b3b80d8
2008-04-25 17:45:52 +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
Nate Begeman
4be30ac0e2 Teach the PruningFunctionCloner how to look through loads with
ConstantExpression GEPs pointing into constant globals.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@50256 91177308-0d34-0410-b5e6-96231b3b80d8
2008-04-25 06:37:06 +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
Evan Cheng
79328661fa Adjust inline cost computation to be less aggressive.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@50222 91177308-0d34-0410-b5e6-96231b3b80d8
2008-04-24 18:42:47 +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
Chris Lattner
c9e495c534 Split some code out of the main SimplifyCFG loop into its own function.
Fix said code to handle merging return instructions together correctly
when handling multiple return values.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@50199 91177308-0d34-0410-b5e6-96231b3b80d8
2008-04-24 00:01:19 +00:00
Devang Patel
6829157f49 Check type instead of no. of operands.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@50179 91177308-0d34-0410-b5e6-96231b3b80d8
2008-04-23 20:18:29 +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
4af6ad3789 simplify code for propagation of constant arguments into
callees.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@50142 91177308-0d34-0410-b5e6-96231b3b80d8
2008-04-23 06:16:27 +00:00
Chris Lattner
e9625c6c88 Fix a number of bugs in ipconstantprop, simplify the code, fit in 80 cols,
fix read after free bug (PR2238).


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@50141 91177308-0d34-0410-b5e6-96231b3b80d8
2008-04-23 05:59:23 +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