Commit Graph

109 Commits

Author SHA1 Message Date
Benjamin Kramer
ae707bd559 InstSimplify: Don't try to replace an extractvalue/insertvalue pair with the original value if types don't match.
Fixes clang selfhost.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@139120 91177308-0d34-0410-b5e6-96231b3b80d8
2011-09-05 18:16:19 +00:00
Duncan Sands
dabc280672 Add some simple insertvalue simplifications, for the purpose of cleaning
up do-nothing exception handling code produced by dragonegg.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@139113 91177308-0d34-0410-b5e6-96231b3b80d8
2011-09-05 06:52:48 +00:00
Eli Friedman
f23d4adbfa Revert r137781; I agree with Duncan's comment that the situation in question is clearly impossible given the current structure of the code.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@137853 91177308-0d34-0410-b5e6-96231b3b80d8
2011-08-17 19:31:49 +00:00
Eli Friedman
207634263c Extend the undef ^ undef idiom once more. No testcase: I can't figure out how to actually trigger the codepath in question at the moment, but it might get exposed in the future.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@137781 91177308-0d34-0410-b5e6-96231b3b80d8
2011-08-16 22:38:34 +00:00
Duncan Sands
c9d904ee2c Fix what seems an obvious typo. Patch by Ivan Krasin. Problem
reported at http://habrahabr.ru/blogs/compilers/125626/.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@136865 91177308-0d34-0410-b5e6-96231b3b80d8
2011-08-04 10:02:21 +00:00
Duncan Sands
f56138d4ae Add helper function for getting true/false constants in a uniform
way for i1 and vector of i1 types.  Use these to make some code
more self-documenting.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@136079 91177308-0d34-0410-b5e6-96231b3b80d8
2011-07-26 15:03:53 +00:00
Jay Foad
a9203109f4 Convert GetElementPtrInst to use ArrayRef.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@135904 91177308-0d34-0410-b5e6-96231b3b80d8
2011-07-25 09:48:08 +00:00
Jay Foad
dab3d29605 Convert ConstantExpr::getGetElementPtr and
ConstantExpr::getInBoundsGetElementPtr to use ArrayRef.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@135673 91177308-0d34-0410-b5e6-96231b3b80d8
2011-07-21 14:31:17 +00:00
Jay Foad
b9b54ebfed Convert SimplifyGEPInst to use ArrayRef.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@135482 91177308-0d34-0410-b5e6-96231b3b80d8
2011-07-19 15:07:52 +00:00
Jay Foad
1d2f569c34 Use ArrayRef in ConstantFoldInstOperands and ConstantFoldCall.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@135477 91177308-0d34-0410-b5e6-96231b3b80d8
2011-07-19 13:32:40 +00:00
Chris Lattner
db125cfaf5 land David Blaikie's patch to de-constify Type, with a few tweaks.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@135375 91177308-0d34-0410-b5e6-96231b3b80d8
2011-07-18 04:54:35 +00:00
Dan Gohman
68c0dbc14f Improve constant folding of undef for cmp and select operators.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@134223 91177308-0d34-0410-b5e6-96231b3b80d8
2011-07-01 01:03:43 +00:00
Duncan Sands
e864b5b840 The comparision "max(x,y)==x" is equivalent to "x>=y". Since the max is
often expressed as "x >= y ? x : y", there is a good chance we can extract
the existing "x >= y" from it and use that as a replacement for "max(x,y)==x".


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@131049 91177308-0d34-0410-b5e6-96231b3b80d8
2011-05-07 16:56:49 +00:00
Eli Friedman
b6e7cd655c PR9838: Fix transform introduced in r127064 to not trigger when only one side of the icmp is an exact shift.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@130954 91177308-0d34-0410-b5e6-96231b3b80d8
2011-05-05 21:59:18 +00:00
Duncan Sands
8140ad32ce Add variations on: max(x,y) >= min(x,z) folds to true. This isn't that common,
but according to my super-optimizer there are only two missed simplifications
of -instsimplify kind when compiling bzip2, and this is one of them.  It amuses
me to have bzip2 be perfectly optimized as far as instsimplify goes!


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@130840 91177308-0d34-0410-b5e6-96231b3b80d8
2011-05-04 16:05:05 +00:00
Duncan Sands
ad20681cde Implement some basic simplifications involving min/max, for example
max(a,b) >= a -> true.  According to my super-optimizer, these are
by far the most common simplifications (of the -instsimplify kind)
that occur in the testsuite and aren't caught by -std-compile-opts.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@130780 91177308-0d34-0410-b5e6-96231b3b80d8
2011-05-03 19:53:10 +00:00
Duncan Sands
448a6d3cc2 Fix PR9579: when simplifying a compare to "true" or "false", and it was
a vector compare, generate a vector result rather than i1 (and crashing).


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@130706 91177308-0d34-0410-b5e6-96231b3b80d8
2011-05-02 18:51:41 +00:00
Duncan Sands
f24ed77d24 Move some rem transforms out of instcombine and into instsimplify.
This automagically provides a transform noticed by my super-optimizer
as occurring quite often: "rem x, (select cond, x, 1)" -> 0.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@130694 91177308-0d34-0410-b5e6-96231b3b80d8
2011-05-02 16:27:02 +00:00
Jay Foad
562b84b3ae Don't include Operator.h from InstrTypes.h.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@129271 91177308-0d34-0410-b5e6-96231b3b80d8
2011-04-11 09:35:34 +00:00
Nick Lewycky
a0e2f38b25 Fix two cases I forgot to update when doing a mental "getSwappedPredicate".
Thanks Duncan Sands!


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@127323 91177308-0d34-0410-b5e6-96231b3b80d8
2011-03-09 08:20:06 +00:00
Nick Lewycky
84dd4fa2e3 Add another micro-optimization. Apologies for the lack of refactoring, but I
gave up when I realized I couldn't come up with a good name for what the
refactored function would be, to describe what it does.

This is PR9343 test12, which is test3 with arguments reordered. Whoops!


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@127318 91177308-0d34-0410-b5e6-96231b3b80d8
2011-03-09 06:26:03 +00:00
Nick Lewycky
58bfcdbcf6 Thread comparisons over udiv/sdiv/ashr/lshr exact and lshr nuw/nsw whenever
possible. This goes into instcombine and instsimplify because instsimplify
doesn't need to check hasOneUse since it returns (almost exclusively) constants.

This fixes PR9343 #4 #5 and #8!


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@127064 91177308-0d34-0410-b5e6-96231b3b80d8
2011-03-05 05:19:11 +00:00
Nick Lewycky
e2ee753bc4 Revert broken srem logic from r126991.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@127021 91177308-0d34-0410-b5e6-96231b3b80d8
2011-03-04 19:26:08 +00:00
Nick Lewycky
786792784e Fold "icmp pred (srem X, Y), Y" like we do for urem. Handle signed comparisons
in the urem case, though not the other way around. This is enough to get #3 from
PR9343!


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@126991 91177308-0d34-0410-b5e6-96231b3b80d8
2011-03-04 10:06:52 +00:00
Nick Lewycky
3a73e343d0 Teach instruction simplify to use constant ranges to solve problems of the form
"icmp pred %X, CI" and a number of examples where "%X = binop %Y, CI2".

Some of these cases (div and rem) used to make it through opt -O2, but the
others are probably now making code elsewhere redundant (probably instcombine).


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@126988 91177308-0d34-0410-b5e6-96231b3b80d8
2011-03-04 07:00:57 +00:00
Nick Lewycky
88cd0aadb2 Optimize "icmp pred (urem X, Y), Y" --> true/false depending on pred. There's
more work to do here, "icmp ult (urem X, 10), 11" doesn't optimize away yet.
Fixes example 3 from PR9343!


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@126741 91177308-0d34-0410-b5e6-96231b3b80d8
2011-03-01 08:15:50 +00:00
Benjamin Kramer
38f7f66fcc Move "A | ~(A & ?) -> -1" from InstCombine to InstructionSimplify.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@126082 91177308-0d34-0410-b5e6-96231b3b80d8
2011-02-20 15:20:01 +00:00
Duncan Sands
5380d28070 Remove pointless blank line.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@125463 91177308-0d34-0410-b5e6-96231b3b80d8
2011-02-13 18:11:05 +00:00
Duncan Sands
52fb846578 Teach instsimplify that X+Y>=X+Z is the same as Y>=Z if neither side overflows,
plus some variations of this.  According to my auto-simplifier this occurs a lot
but usually in combination with max/min idioms.  Because max/min aren't handled
yet this unfortunately doesn't have much effect in the testsuite.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@125462 91177308-0d34-0410-b5e6-96231b3b80d8
2011-02-13 17:15:40 +00:00
Duncan Sands
ffeb98ad3b Formatting and comment tweaks.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@125200 91177308-0d34-0410-b5e6-96231b3b80d8
2011-02-09 17:45:03 +00:00
Chris Lattner
81a0dc9115 Teach instsimplify some tricks about exact/nuw/nsw shifts.
improve interfaces to instsimplify to take this info.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@125196 91177308-0d34-0410-b5e6-96231b3b80d8
2011-02-09 17:15:04 +00:00
Chris Lattner
aeaf3d484b Rework InstrTypes.h so to reduce the repetition around the NSW/NUW/Exact
versions of creation functions.  Eventually, the "insertion point" versions
of these should just be removed, we do have IRBuilder afterall.

Do a massive rewrite of much of pattern match.  It is now shorter and less
redundant and has several other widgets I will be using in other patches.
Among other changes, m_Div is renamed to m_IDiv (since it only matches 
integer divides) and m_Shift is gone (it used to match all binops!!) and
we now have m_LogicalShift for the one client to use.

Enhance IRBuilder to have "isExact" arguments to things like CreateUDiv
and reduce redundancy within IRbuilder by having these methods chain to
each other more instead of duplicating code.




git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@125194 91177308-0d34-0410-b5e6-96231b3b80d8
2011-02-09 17:00:45 +00:00
Duncan Sands
163a84bbce Add an m_Div pattern for matching either a udiv or an sdiv and use it
to simplify the "(X/Y)*Y->X when the division is exact" transform.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@125004 91177308-0d34-0410-b5e6-96231b3b80d8
2011-02-07 09:36:32 +00:00
Chris Lattner
c6ee9181a5 teach instsimplify to transform (X / Y) * Y to X
when the div is an exact udiv.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@124994 91177308-0d34-0410-b5e6-96231b3b80d8
2011-02-06 22:05:31 +00:00
Anders Carlsson
479b4b9ef0 Fix another warning.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@124961 91177308-0d34-0410-b5e6-96231b3b80d8
2011-02-05 18:33:43 +00:00
Duncan Sands
50ca4d37f7 Improve threading of comparisons over select instructions (spotted by my
auto-simplifier).  This has a big impact on Ada code, but not much else.
Unfortunately the impact is mostly negative!  This is due to PR9004 (aka
SCCP failing to resolve conditional branch conditions in the destination
blocks of the branch), in which simple correlated expressions are not
resolved but complicated ones are, so simplifying has a bad effect!


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@124788 91177308-0d34-0410-b5e6-96231b3b80d8
2011-02-03 09:37:39 +00:00
Duncan Sands
4b720718fb Reenable the transform "(X*Y)/Y->X" when the multiplication is known not to
overflow (nsw flag), which was disabled because it breaks 254.gap.  I have
informed the GAP authors of the mistake in their code, and arranged for the
testsuite to use -fwrapv when compiling this benchmark.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@124746 91177308-0d34-0410-b5e6-96231b3b80d8
2011-02-02 20:52:00 +00:00
Duncan Sands
f9e4a986c0 Add a m_Undef pattern for convenience. This is so that code that uses
pattern matching can also pattern match undef, creating a more uniform
style.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@124657 91177308-0d34-0410-b5e6-96231b3b80d8
2011-02-01 09:06:20 +00:00
Duncan Sands
7681c6da60 Have m_One also match constant vectors for which every element is 1.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@124655 91177308-0d34-0410-b5e6-96231b3b80d8
2011-02-01 08:39:12 +00:00
Duncan Sands
7af00c0f6e Commit 124487 broke 254.gap. See if disabling the part that might be triggered
by PR9088 fixes things.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@124561 91177308-0d34-0410-b5e6-96231b3b80d8
2011-01-30 18:24:20 +00:00
Duncan Sands
1895e98ef3 Transform (X/Y)*Y into X if the division is exact. Instcombine already knows how
to do this and more, but would only do it if X/Y had only one use.  Spotted as the
most common missed simplification in SPEC by my auto-simplifier, now that it knows
about nuw/nsw/exact flags.  This removes a bunch of multiplications from 447.dealII
and 483.xalancbmk.  It also removes a lot from tramp3d-v4, which results in much
more inlining.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@124560 91177308-0d34-0410-b5e6-96231b3b80d8
2011-01-30 18:03:50 +00:00
Nick Lewycky
5413880654 Fix comment.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@124544 91177308-0d34-0410-b5e6-96231b3b80d8
2011-01-29 19:55:23 +00:00
Frits van Bommel
1fca2c32cc Move InstCombine's knowledge of fdiv to SimplifyInstruction().
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@124534 91177308-0d34-0410-b5e6-96231b3b80d8
2011-01-29 15:26:31 +00:00
Duncan Sands
79f4eea7a3 This dyn_cast should be a cast. Pointed out by Frits van Bommel.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@124497 91177308-0d34-0410-b5e6-96231b3b80d8
2011-01-28 18:53:08 +00:00
Duncan Sands
a3e292c7e8 Thread divisions over selects and phis. This doesn't fire much and has basically
zero effect on the testsuite (it improves two Ada testcases).


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@124496 91177308-0d34-0410-b5e6-96231b3b80d8
2011-01-28 18:50:50 +00:00
Duncan Sands
593faa53fa My auto-simplifier noticed that ((X/Y)*Y)/Y occurs several times in SPEC
benchmarks, and that it can be simplified to X/Y.  (In general you can only
simplify (Z*Y)/Y to Z if the multiplication did not overflow; if Z has the
form "X/Y" then this is the case).  This patch implements that transform and
moves some Div logic out of instcombine and into InstructionSimplify.
Unfortunately instcombine gets in the way somewhat, since it likes to change
(X/Y)*Y into X-(X rem Y), so I had to teach instcombine about this too.
Finally, thanks to the NSW/NUW flags, sometimes we know directly that "Z*Y"
does not overflow, because the flag says so, so I added that logic too.  This
eliminates a bunch of divisions and subtractions in 447.dealII, and has good
effects on some other benchmarks too.  It seems to have quite an effect on
tramp3d-v4 but it's hard to say if it's good or bad because inlining decisions
changed, resulting in massive changes all over.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@124487 91177308-0d34-0410-b5e6-96231b3b80d8
2011-01-28 16:51:11 +00:00
Duncan Sands
d70d1a5c44 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.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@124183 91177308-0d34-0410-b5e6-96231b3b80d8
2011-01-25 09:38:29 +00:00
Duncan Sands
9d32f60a6f At -O123 the early-cse pass is run before instcombine has run. According to my
auto-simplier the transform most missed by early-cse is (zext X) != 0 -> X != 0.
This patch adds this transform and some related logic to InstructionSimplify
and removes some of the logic from instcombine (unfortunately not all because
there are several situations in which instcombine can improve things by making
new instructions, whereas instsimplify is not allowed to do this).  At -O2 this
often results in more than 15% more simplifications by early-cse, and results in
hundreds of lines of bitcode being eliminated from the testsuite.  I did see some
small negative effects in the testsuite, for example a few additional instructions
in three programs.  One program, 483.xalancbmk, got an additional 35 instructions,
which seems to be due to a function getting an additional instruction and then
being inlined all over the place.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@123911 91177308-0d34-0410-b5e6-96231b3b80d8
2011-01-20 13:21:55 +00:00
Duncan Sands
b2f3c383ec For completeness, generalize the (X + Y) - Y -> X transform and add X - (X + 1) -> -1.
These were not recommended by my auto-simplifier since they don't fire often enough.
However they do fire from time to time, for example they remove one subtraction from
the final bitcode for 483.xalancbmk.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@123755 91177308-0d34-0410-b5e6-96231b3b80d8
2011-01-18 11:50:19 +00:00
Duncan Sands
fe02c69f84 Simplify (X<<1)-X into X. According to my auto-simplier this is the most common missed
simplification in fully optimized code.  It occurs sporadically in the testsuite, and
many times in 403.gcc: the final bitcode has 131 fewer subtractions after this change.
The reason that the multiplies are not eliminated is the same reason that instcombine
did not catch this: they are used by other instructions (instcombine catches this with
a more general transform which in general is only profitable if the operands have only
one use).


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@123754 91177308-0d34-0410-b5e6-96231b3b80d8
2011-01-18 09:24:58 +00:00