Commit Graph

2231 Commits

Author SHA1 Message Date
Chris Lattner
0dabb0b177 do not try to analyze bitcasts from i64 to <2 x i32> in ComputedMaskedBits. While
we could do this, doing so requires adjusting the demanded mask and the code isn't 
doing that yet.  This fixes PR4495


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@74699 91177308-0d34-0410-b5e6-96231b3b80d8
2009-07-02 16:04:08 +00:00
Dan Gohman
6cc18fedf8 Fix an instcombine abort on a scalar-to-vector bitcast. This fixes PR4487.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@74646 91177308-0d34-0410-b5e6-96231b3b80d8
2009-07-01 21:38:46 +00:00
Dan Gohman
cffddcd726 Don't cache PHI exit values from exhaustive evaluations, because
an individual exhaustive evaluation reflects only the exit value
implied by an individual exit, which may differ from the actual
exit value of the loop if there are other exits. This fixes PR4477.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@74447 91177308-0d34-0410-b5e6-96231b3b80d8
2009-06-29 20:34:13 +00:00
Dan Gohman
f7ca1611e2 Don't try to split a loop when the controlling icmp instruction
doesn't have an IV-based operand. This fixes PR4471.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@74399 91177308-0d34-0410-b5e6-96231b3b80d8
2009-06-27 22:58:27 +00:00
Dan Gohman
4b35f83b91 Teach LoopSimplify how to merge multiple loop exits into a single exit,
when one of them can be converted to a trivial icmp and conditional
branch.

This addresses what is essentially a phase ordering problem.
SimplifyCFG knows how to do this transformation, but it doesn't do so
if the primary block has any instructions in it other than an icmp and
a branch. In the given testcase, the block contains other instructions,
however they are loop-invariant and can be hoisted. SimplifyCFG doesn't
have LoopInfo though, so it can't hoist them. And, it's important that
the blocks be merged before LoopRotation, as it doesn't support
multiple-exit loops.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@74396 91177308-0d34-0410-b5e6-96231b3b80d8
2009-06-27 21:30:38 +00:00
Dan Gohman
de53dc03f5 When a value is used multiple times within a single PHI, instructions
inserted to replace that value must dominate all of of the basic
blocks associated with the uses of the value in the PHI, not just
one of them.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@74376 91177308-0d34-0410-b5e6-96231b3b80d8
2009-06-27 05:16:57 +00:00
Dan Gohman
16bdfdb178 Add some testcases for some of the recent ScalarEvolution bug fixes.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@74353 91177308-0d34-0410-b5e6-96231b3b80d8
2009-06-26 22:54:11 +00:00
Dan Gohman
6b9c959c61 Fix LCSSA to avoid emitting a PHI node for the unwind destination of
an invoke instruction, since the value isn't really live across that
edge.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@74242 91177308-0d34-0410-b5e6-96231b3b80d8
2009-06-26 00:31:13 +00:00
Dan Gohman
e5aceed168 Simplify [su]max(MAX, n) to MAX. This comes up in loop tripcount
computations in loops with multiple exits.

Adjust the testcase for PR4436 so that the relevant portion isn't
optimized away.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@74073 91177308-0d34-0410-b5e6-96231b3b80d8
2009-06-24 14:46:22 +00:00
Dan Gohman
32a81a3f6d When inserting code into a loop preheader, insert it before the
terminator, instead of after the last phi. This fixes a bug
exposed by ScalarEvolution analyzing more kinds of loops.
This fixes PR4436.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@74072 91177308-0d34-0410-b5e6-96231b3b80d8
2009-06-24 14:31:06 +00:00
Dan Gohman
51f53b7f5a Fix ScalarEvolution's backedge-taken count computations to check for
overflow when computing a integer division to round up.

Thanks to Nick Lewycky for noticing this!


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@73862 91177308-0d34-0410-b5e6-96231b3b80d8
2009-06-21 23:46:38 +00:00
Nick Lewycky
e47f59db44 Expand this test to handle more cases (remainder and shifts) of zero.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@73839 91177308-0d34-0410-b5e6-96231b3b80d8
2009-06-21 01:56:41 +00:00
Chris Lattner
1db6866147 implement PR4424: 0/x is always 0 for integer division.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@73835 91177308-0d34-0410-b5e6-96231b3b80d8
2009-06-21 01:15:55 +00:00
Dan Gohman
97b52b2a88 Tweak this test to be a little less unusual.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@73808 91177308-0d34-0410-b5e6-96231b3b80d8
2009-06-20 00:40:56 +00:00
Dan Gohman
763bad1a2b Generalize isLoopGuardedByCond's checking to consider two
SCEVUnknowns with identical Instructions to be equal. This allows
it to analze cases such as the attached testcase, where the front-end
has cloned the loop controlling expression. Along with r73805, this
lets IndVarSimplify eliminate all the sign-extend casts in the
loop in the attached testcase.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@73807 91177308-0d34-0410-b5e6-96231b3b80d8
2009-06-20 00:35:32 +00:00
Dan Gohman
958e292c7a Don't (unconditionally) use getSCEVAtScope to simplify the step
expression in IVUsers, because in the case of a use of a non-linear
addrec outside of a loop, this causes the addrec to be evaluated as
a linear addrec.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@73774 91177308-0d34-0410-b5e6-96231b3b80d8
2009-06-19 17:33:15 +00:00
Chris Lattner
79c740ff47 make jump threading handle lexically identical compare instructions
as if they were multiple uses of the same instruction.  This interacts
well with the existing loadpre that j-t does to open up many new jump
threads earlier.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@73768 91177308-0d34-0410-b5e6-96231b3b80d8
2009-06-19 16:27:56 +00:00
Nick Lewycky
9683f18174 Teach jump threading to look at comparisons between phi nodes and non-constants.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@73755 91177308-0d34-0410-b5e6-96231b3b80d8
2009-06-19 04:56:29 +00:00
Chris Lattner
6a35b40250 Improve tail call elim to move loads above readonly calls
when it allows forming a tail call.  Patch by Frits van
Bommel.  This implements PR4323.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@73752 91177308-0d34-0410-b5e6-96231b3b80d8
2009-06-19 04:22:16 +00:00
Chris Lattner
849832c0fb part of PR4405: disable a contentious optimization for
strcmp -> memcmp when the lengths of the strings are unknown.

Patch by Nick Lewycky!


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@73751 91177308-0d34-0410-b5e6-96231b3b80d8
2009-06-19 04:17:36 +00:00
Dan Gohman
4e8a98519e Remove the code from IVUsers that attempted to handle
casted induction variables in cases where the cast
isn't foldable. It ended up being a pessimization in
many cases. This could be fixed, but it would require
a bunch of complicated code in IVUsers' clients. The
advantages of this approach aren't visible enough to
justify it at this time.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@73706 91177308-0d34-0410-b5e6-96231b3b80d8
2009-06-18 16:54:06 +00:00
Dan Gohman
fd3daa74c2 Generalize the zext(trunc(t) & C) instcombine to work even with
C is not a low-bits mask, and add a similar instcombine for
zext((trunc(t) & C) ^ C).


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@73705 91177308-0d34-0410-b5e6-96231b3b80d8
2009-06-18 16:30:21 +00:00
Dan Gohman
a392c788be Instcombine zext(trunc(x) & mask) to x&mask, even if the trunc has
multiple users.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@73656 91177308-0d34-0410-b5e6-96231b3b80d8
2009-06-17 23:17:05 +00:00
Dan Gohman
559254b697 Add -disable-output to a bunch of tests that don't care about the output.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@73633 91177308-0d34-0410-b5e6-96231b3b80d8
2009-06-17 20:56:26 +00:00
Dale Johannesen
42c3f554f4 This fixes a bug introduced in 72661, which can
move loads back past a check that the load address
is valid, see new testcase.  The test that went
in with 72661 has exactly this case, except that
the conditional it's moving past is checking
something else; I've settled for changing that
test to reference a global, not a pointer.  It
may be possible to scan all the tests you pass and
make sure none of them are checking any component
of the address, but it's not trivial and I'm not
trying to do that here.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@73632 91177308-0d34-0410-b5e6-96231b3b80d8
2009-06-17 20:48:23 +00:00
Eli Friedman
af79ae558f Correct an accidental duplication of the test (patch doesn't handle
creating new files very well).



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@73599 91177308-0d34-0410-b5e6-96231b3b80d8
2009-06-17 03:05:00 +00:00
Eli Friedman
a999a511f7 PR3439: Correct a silly mistake in the SimplifyDemandedUseBits code for
SRem.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@73598 91177308-0d34-0410-b5e6-96231b3b80d8
2009-06-17 02:57:36 +00:00
Dan Gohman
c6ac322c1c Generalize a few more instcombines to be vector/scalar-independent.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@73541 91177308-0d34-0410-b5e6-96231b3b80d8
2009-06-16 19:55:29 +00:00
Dan Gohman
61ffa8e373 Instcombine's ShrinkDemandedConstant may strip bits out of constants,
obscuring what would otherwise be a low-bits mask.  Use ComputeMaskedBits
to compute what ShrinkDemandedConstant knew about to reconstruct a
low-bits mask value.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@73540 91177308-0d34-0410-b5e6-96231b3b80d8
2009-06-16 19:52:01 +00:00
Chris Lattner
3d0cbbe0ad Testcase for r73506
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@73508 91177308-0d34-0410-b5e6-96231b3b80d8
2009-06-16 17:23:25 +00:00
Dan Gohman
6de29f8d96 Support vector casts in more places, fixing a variety of assertion
failures.

To support this, add some utility functions to Type to help support
vector/scalar-independent code. Change ConstantInt::get and
ConstantFP::get to support vector types, and add an overload to
ConstantInt::get that uses a static IntegerType type, for
convenience.

Introduce a new getConstant method for ScalarEvolution, to simplify
common use cases.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@73431 91177308-0d34-0410-b5e6-96231b3b80d8
2009-06-15 22:12:54 +00:00
Dale Johannesen
c1f104054d Fix the crash in this test. This is basically the same
problem addressed in 31284, but the patch there only
addressed the case where an invoke is the first thing in
a block.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@73416 91177308-0d34-0410-b5e6-96231b3b80d8
2009-06-15 20:59:27 +00:00
Chris Lattner
d3b295c23f fix testcase to properly check for the patch in r73195.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@73380 91177308-0d34-0410-b5e6-96231b3b80d8
2009-06-15 05:46:02 +00:00
Dan Gohman
bd59d7b603 Implement more aggressive folding of add operand lists when
they contain multiplications of constants with add operations.
This helps simplify several kinds of things; in particular it
helps simplify expressions like ((-1 * (%a + %b)) + %a) to %b,
as expressions like this often come up in loop trip count
computations.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@73361 91177308-0d34-0410-b5e6-96231b3b80d8
2009-06-14 22:58:51 +00:00
Dan Gohman
4d8414f420 Teach SCEVExpander's visitAddRecExpr to reuse an existing canonical
induction variable when the addrec to be expanded does not require
a wider type. This eliminates the need for IndVarSimplify to
micro-manage SCEV expansions, because SCEVExpander now
automatically expands them in the form that IndVarSimplify considers
to be canonical. (LSR still micro-manages its SCEV expansions,
because it's optimizing for the target, rather than for
other optimizations.)

Also, this uses the new getAnyExtendExpr, which has more clever
expression simplification logic than the IndVarSimplify code it
replaces, and this cleans up some ugly expansions in code such as
the included masked-iv.ll testcase.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@73294 91177308-0d34-0410-b5e6-96231b3b80d8
2009-06-13 16:25:49 +00:00
Dan Gohman
e54aba5fa9 Don't do (x - (y - z)) --> (x + (z - y)) on floating-point types, because
it may round differently. This fixes PR4374.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@73243 91177308-0d34-0410-b5e6-96231b3b80d8
2009-06-12 19:23:25 +00:00
Nick Lewycky
8728d7a3ea Given two identical weak functions, produce one internal function and two weak
thunks.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@73230 91177308-0d34-0410-b5e6-96231b3b80d8
2009-06-12 15:56:56 +00:00
Nick Lewycky
f343b69f47 This test is wrong. If you have two weak functions F and G you can't make
either one call the other since either one can be replaced at link time, and
they need to be independent.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@73225 91177308-0d34-0410-b5e6-96231b3b80d8
2009-06-12 13:24:41 +00:00
Chris Lattner
3590abfda0 Fix 4366: store to null in non-default addr space should not be
turned into unreachable.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@73195 91177308-0d34-0410-b5e6-96231b3b80d8
2009-06-11 17:54:56 +00:00
Eli Friedman
b9a4cacc91 PR4340: Run SimplifyDemandedVectorElts on insertelement instructions;
sometimes it can find simplifications that won't be found otherwise.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@73006 91177308-0d34-0410-b5e6-96231b3b80d8
2009-06-06 20:08:03 +00:00
Dan Gohman
ae3a0be92e Split the Add, Sub, and Mul instruction opcodes into separate
integer and floating-point opcodes, introducing
FAdd, FSub, and FMul.

For now, the AsmParser, BitcodeReader, and IRBuilder all preserve
backwards compatability, and the Core LLVM APIs preserve backwards
compatibility for IR producers. Most front-ends won't need to change
immediately.

This implements the first step of the plan outlined here:
http://nondot.org/sabre/LLVMNotes/IntegerOverflow.txt


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@72897 91177308-0d34-0410-b5e6-96231b3b80d8
2009-06-04 22:49:04 +00:00
Dan Gohman
0e19a3f89e Check in test changes that I accidentally left out of r72872.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@72875 91177308-0d34-0410-b5e6-96231b3b80d8
2009-06-04 18:22:31 +00:00
Dan Gohman
68c9344056 Don't attempt to simplify an non-affine IV expression if it can't
be simplified to a loop-invariant value. This fixes PR4315.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@72798 91177308-0d34-0410-b5e6-96231b3b80d8
2009-06-03 19:11:31 +00:00
Evan Cheng
5d16396a33 Avoid infinite looping in AllGlobalLoadUsesSimpleEnoughForHeapSRA(). This can happen when PHI uses are recursively dependent on each other.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@72710 91177308-0d34-0410-b5e6-96231b3b80d8
2009-06-02 00:56:07 +00:00
Eli Friedman
41b33f437f PR4286: Make RewriteLoadUserOfWholeAlloca and
RewriteStoreUserOfWholeAlloca deal with tail padding because 
isSafeUseOfBitCastedAllocation expects them to.  Otherwise, we crash 
trying to erase the bitcast.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@72688 91177308-0d34-0410-b5e6-96231b3b80d8
2009-06-01 09:14:32 +00:00
Owen Anderson
88554df4a2 Be more aggressive in doing LoadPRE by tracing backwards when a block only has
a single predecessor.

Patch by Jakub Staszak.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@72661 91177308-0d34-0410-b5e6-96231b3b80d8
2009-05-31 09:03:40 +00:00
Chris Lattner
0e98e4d299 fix PR4284, a bug in simplifylibcalls handling memcmp. Patch by
Benjamin Kramer!


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@72625 91177308-0d34-0410-b5e6-96231b3b80d8
2009-05-30 18:43:04 +00:00
Nick Lewycky
e3f1fb1ee8 Use Operands.data() instead of &Operands[0] where Operands is a potentially
empty SmallVector.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@72512 91177308-0d34-0410-b5e6-96231b3b80d8
2009-05-28 04:08:10 +00:00
Dan Gohman
c2695eba57 Revert 72493 and replace it with a more conservative fix, for now: don't
rewrite the comparison if there is any implicit extension or truncation
on the induction variable. I'm planning for IVUsers to eventually take
over some of the work of this code, and for it to be generalized.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@72496 91177308-0d34-0410-b5e6-96231b3b80d8
2009-05-27 21:10:47 +00:00
Dan Gohman
ead28bd04b In ChangeCompareStride, when the stride to be reused is truncated to
a smaller type, promoted its offset back up to the type of the new
comparison. This fixes PR4222.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@72493 91177308-0d34-0410-b5e6-96231b3b80d8
2009-05-27 20:00:18 +00:00