Commit Graph

549 Commits

Author SHA1 Message Date
Chris Lattner
7903530b71 remove the last vestiges of llvm::GetConstantStringInfo, in CodeGen.
llvm-svn: 149356
2012-01-31 05:09:17 +00:00
Chris Lattner
b463bd21fc Change ConstantArray::get to form a ConstantDataArray when possible,
kicking in the big win of ConstantDataArray.  As part of this, change
the implementation of GetConstantStringInfo in ValueTracking to work
with ConstantDataArray (and not ConstantArray) making it dramatically,
amazingly, more efficient in the process and renaming it to 
getConstantStringInfo.

This keeps around a GetConstantStringInfo entrypoint that (grossly)
forwards to getConstantStringInfo and constructs the std::string 
required, but existing clients should move over to 
getConstantStringInfo instead.

llvm-svn: 149351
2012-01-31 04:42:22 +00:00
Chris Lattner
ba1715c058 progress making the world safe to ConstantDataVector. While
we're at it, allow PatternMatch's "neg" pattern to match integer
vector negations, and enhance ComputeNumSigned bits to handle
shl of vectors.

llvm-svn: 149082
2012-01-26 21:37:55 +00:00
Chris Lattner
4218b7524c use Constant::getAggregateElement to simplify a bunch of code.
llvm-svn: 148934
2012-01-25 06:48:06 +00:00
Chris Lattner
834679362f Use the right method to get the # elements in a CDS.
llvm-svn: 148897
2012-01-25 01:27:20 +00:00
Chris Lattner
e9cf212d3f teach valuetracking about ConstantDataSequential
llvm-svn: 148790
2012-01-24 07:54:10 +00:00
Dan Gohman
f9fb5b3951 Generalize isSafeToSpeculativelyExecute to work on arbitrary
Values, rather than just Instructions, since it's interesting
for ConstantExprs too.

llvm-svn: 147560
2012-01-04 23:01:09 +00:00
Benjamin Kramer
fba4e88bc2 PatternMatch: Introduce a matcher for instructions with the "exact" bit. Use it to simplify a few matchers.
llvm-svn: 147403
2012-01-01 17:55:30 +00:00
Benjamin Kramer
b5e584392b ComputeMaskedBits: Make knownzero computation more aggressive for ctlz with undef zero.
unsigned foo(unsigned x) { return 31 - __builtin_clz(x); }
now compiles into a single "bsrl" instruction on x86.

llvm-svn: 147255
2011-12-24 17:31:46 +00:00
Nick Lewycky
9adbd36737 Make some intrinsics safe to speculatively execute.
llvm-svn: 147036
2011-12-21 05:52:02 +00:00
Dan Gohman
1add31cc93 Move Instruction::isSafeToSpeculativelyExecute out of VMCore and
into Analysis as a standalone function, since there's no need for
it to be in VMCore. Also, update it to use isKnownNonZero and
other goodies available in Analysis, making it more precise,
enabling more aggressive optimization.

llvm-svn: 146610
2011-12-14 23:49:11 +00:00
Chad Rosier
7096fea51c Probably not a good idea to convert a single vector load into a memcpy. We
don't do this now, but add a test case to prevent this from happening in the
future.
Additional test for rdar://9892684

llvm-svn: 145879
2011-12-06 00:19:08 +00:00
Nadav Rotem
1a91e4381d Add support for vectors of pointers.
llvm-svn: 145801
2011-12-05 06:29:09 +00:00
Duncan Sands
97cc6da56c Fix a theoretical problem (not seen in the wild): if different instances of a
weak variable are compiled by different compilers, such as GCC and LLVM, while
LLVM may increase the alignment to the preferred alignment there is no reason to
think that GCC will use anything more than the ABI alignment.  Since it is the
GCC version that might end up in the final program (as the linkage is weak), it
is wrong to increase the alignment of loads from the global up to the preferred
alignment as the alignment might only be the ABI alignment.

Increasing alignment up to the ABI alignment might be OK, but I'm not totally
convinced that it is.  It seems better to just leave the alignment of weak
globals alone.

llvm-svn: 145413
2011-11-29 18:26:38 +00:00
Eli Friedman
473a76a0df Make SelectionDAG::InferPtrAlignment use llvm::ComputeMaskedBits instead of duplicating the logic for globals. Make llvm::ComputeMaskedBits handle GlobalVariables slightly more aggressively, to match what InferPtrAlignment knew how to do.
llvm-svn: 145304
2011-11-28 22:48:22 +00:00
Duncan Sands
3c1878ef53 Fix a crash in which a multiplication was being reported as being both negative
and positive: positive, because it could be directly computed to be positive;
negative, because the nsw flags means it is either negative or undefined (the
multiplication always overflowed).

llvm-svn: 145104
2011-11-23 16:26:47 +00:00
Duncan Sands
3483c23658 A shift of a power of two is a power of two or zero.
For completeness - not spotted in the wild.

llvm-svn: 143211
2011-10-28 18:30:05 +00:00
Duncan Sands
ca325638c8 Reapply commit 143028 with a fix: the problem was casting a ConstantExpr Mul
using BinaryOperator (which only works for instructions) when it should have
been a cast to OverflowingBinaryOperator (which also works for constants).
While there, correct a few other dubious looking uses of BinaryOperator.
Thanks to Chad Rosier for the testcase.  Original commit message:
My super-optimizer noticed that we weren't folding this expression to
true: (x *nsw x) sgt 0, where x = (y | 1).  This occurs in 464.h264ref.

llvm-svn: 143125
2011-10-27 19:16:21 +00:00
Bob Wilson
2ca603d9b7 Revert Duncan's r143028 expression folding which appears to be the culprit
behind a compile failure on 483.xalancbmk.

llvm-svn: 143102
2011-10-27 15:47:25 +00:00
Duncan Sands
5c8fa99c32 The maximum power of 2 dividing a power of 2 is itself. This occurs
in 403.gcc and was spotted by my super-optimizer.

llvm-svn: 143054
2011-10-26 20:55:21 +00:00
Duncan Sands
c463f54342 My super-optimizer noticed that we weren't folding this expression to
true: (x *nsw x) sgt 0, where x = (y | 1).  This occurs in 464.h264ref.

llvm-svn: 143028
2011-10-26 15:31:51 +00:00
Nick Lewycky
21a67a1454 "@string = constant i8 0" is a value i8* string of length zero. Analyze that
correctly in GetStringLength, fixing PR11181!

llvm-svn: 142558
2011-10-20 00:34:35 +00:00
Frits van Bommel
6c24f9c277 Migrate LLVM and Clang to use the new makeArrayRef(...) functions where previously explicit non-default constructors were used.
Mostly mechanical with some manual reformatting.

llvm-svn: 135390
2011-07-18 12:00:32 +00:00
Chris Lattner
e1fe7061ce land David Blaikie's patch to de-constify Type, with a few tweaks.
llvm-svn: 135375
2011-07-18 04:54:35 +00:00
Jay Foad
88fb4f4597 Convert InsertValueInst and ExtractValueInst APIs to use ArrayRef.
llvm-svn: 135040
2011-07-13 10:26:04 +00:00
Nick Lewycky
4a0f5218f2 Move onlyUsedByLifetimeMarkers to ValueTracking so that it can be used by other
passes as well.

llvm-svn: 133904
2011-06-27 04:20:45 +00:00
Chad Rosier
b87c4a6945 Renamed llvm.x86.sse42.crc32 intrinsics; crc64 doesn't exist.
crc32.[8|16|32] have been renamed to .crc32.32.[8|16|32] and
crc64.[8|16|32] have been renamed to .crc32.64.[8|64].

llvm-svn: 132163
2011-05-26 23:13:19 +00:00
Chris Lattner
c277b19e97 Teach valuetracking that byval arguments with a specified alignment are
aligned.

Teach memcpyopt to not give up all hope when confonted with an underaligned
memcpy feeding an overaligned byval.  If the *source* of the memcpy can be
determined to be adequeately aligned, or if it can be forced to be, we can
eliminate the memcpy.

This addresses PR9794.  We now compile the example into:

define i32 @f(%struct.p* nocapture byval align 8 %q) nounwind ssp {
entry:
  %call = call i32 @g(%struct.p* byval align 8 %q) nounwind
  ret i32 %call
}

in both x86-64 and x86-32 mode.  We still don't get a tailcall though,
because tailcalls apparently can't handle byval.

llvm-svn: 131884
2011-05-23 00:03:39 +00:00
Evan Cheng
a2e8770368 Teach ValueTracking about x86 crc32 intrinsics.
llvm-svn: 131861
2011-05-22 18:25:30 +00:00
Chris Lattner
0304b82f80 Fix a ton of comment typos found by codespell. Patch by
Luis Felipe Strano Moraes!

llvm-svn: 129558
2011-04-15 05:18:47 +00:00
Eli Friedman
823b0d6c77 Don't assume something which might be a constant expression is an instruction.
Based on PR9429, but no testcase because I can't figure out how to trigger it
anymore given other changes to the relevant code.

llvm-svn: 128781
2011-04-02 22:11:56 +00:00
Nick Lewycky
e8f6eb49ee Fix INT_MIN gotcha pointed out by Eli Friedman.
llvm-svn: 128028
2011-03-21 21:40:32 +00:00
Benjamin Kramer
5986a24bae Teach ComputeMaskedBits about sub nsw.
llvm-svn: 127548
2011-03-12 17:18:11 +00:00
Benjamin Kramer
d4ea449e7e ComputeMaskedBits: sub falls through to add, and sub doesn't have the same overflow semantics as add.
Should fix the selfhost failures that started with r127463.

llvm-svn: 127465
2011-03-11 14:46:49 +00:00
Nick Lewycky
cf0e3e88df Teach ComputeMaskedBits about nsw on add. I don't think there's anything we can
do with nuw here, but sub and mul should be given similar treatment.
Fixes PR9343 #15!

llvm-svn: 127463
2011-03-11 09:00:19 +00:00
Duncan Sands
41075b3ffb Fix PR9331. Simplified version of a patch by Jakub Staszak.
llvm-svn: 127243
2011-03-08 12:39:03 +00:00
Nick Lewycky
2cbaf887bb Add more analysis of the sign bit of an srem instruction. If the LHS is negative
then the result could go either way. If it's provably positive then so is the
srem. Fixes PR9343 #7!

llvm-svn: 127146
2011-03-07 01:50:10 +00:00
Nick Lewycky
fe02856d37 Fix comment.
llvm-svn: 126645
2011-02-28 09:18:11 +00:00
Nick Lewycky
dcc97b5f44 srem doesn't actually have the same resulting sign as its numerator, you could
also have a zero when numerator = denominator. Reverts parts of r126635 and
r126637.

llvm-svn: 126644
2011-02-28 09:17:39 +00:00
Nick Lewycky
dd5df7ef0a Teach value tracking to make use of flags in more situations.
llvm-svn: 126642
2011-02-28 08:02:21 +00:00
Nick Lewycky
aa03b76c53 Teach ValueTracking to look at the dividend when determining the sign bit of an
srem instruction.

llvm-svn: 126637
2011-02-28 06:52:12 +00:00
Chris Lattner
90786c35a5 Stores of null pointers should turn into memset, we weren't recognizing
them as splat values.

llvm-svn: 126041
2011-02-19 19:35:49 +00:00
Nick Lewycky
6380885ba1 Tolerate degenerate phi nodes that can occur in the middle of optimization
passes. Fixes PR9112. Patch by Jakub Staszak!

llvm-svn: 125319
2011-02-10 23:54:10 +00:00
Duncan Sands
659237307a Add a m_SignBit pattern for convenience.
llvm-svn: 124656
2011-02-01 08:50:33 +00:00
Duncan Sands
0587f785bf Fix typo: should have been testing that X was odd, not V.
llvm-svn: 124533
2011-01-29 13:27:00 +00:00
Duncan Sands
803522ec6f APInt has a method for determining whether a number is a power of 2
which is more efficient than countPopulation - use it.

llvm-svn: 124283
2011-01-26 08:44:16 +00:00
Duncan Sands
017a3d76f7 In which I discover that zero+zero is zero, d'oh!
llvm-svn: 124188
2011-01-25 15:14:15 +00:00
Duncan Sands
4d8a541ae2 See if this fixes llvm-gcc bootstrap.
llvm-svn: 124184
2011-01-25 12:15:09 +00:00
Duncan Sands
92b081bd42 According to my auto-simplifier the most common missed simplifications in
optimized code are:
  (non-negative number)+(power-of-two) != 0 -> true
and
  (x | 1) != 0 -> true
Instcombine knows about the second one of course, but only does it if X|1
has only one use.  These fire thousands of times in the testsuite.

llvm-svn: 124183
2011-01-25 09:38:29 +00:00
Dan Gohman
db0dc19c04 Give GetUnderlyingObject a TargetData, to keep it in sync
with BasicAA's DecomposeGEPExpression, which recently began
using a TargetData. This fixes PR8968, though the testcase
is awkward to reduce.

Also, update several off GetUnderlyingObject's users
which happen to have a TargetData handy to pass it in.

llvm-svn: 124134
2011-01-24 18:53:32 +00:00