Commit Graph

47 Commits

Author SHA1 Message Date
Nick Lewycky
7e0e166d17 Surprisingly, we missed a trivial case here. Fix that!
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@164814 91177308-0d34-0410-b5e6-96231b3b80d8
2012-09-28 09:33:53 +00:00
Nick Lewycky
466e0f38d3 Prefer shuffles to selects. Backends love shuffles!
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@164763 91177308-0d34-0410-b5e6-96231b3b80d8
2012-09-27 08:33:56 +00:00
Nuno Lopes
75564e3514 fix infinite loop in instcombine in the presence of a (malformed) self-referencing select inst.
This can happen as long as the instruction is not reachable. Instcombine does generate these unreachable malformed selects when doing RAUW

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@160874 91177308-0d34-0410-b5e6-96231b3b80d8
2012-07-27 18:03:57 +00:00
Pete Cooper
7971de4178 Simplify demanded bits of select sources where the condition is a constant vector
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@160835 91177308-0d34-0410-b5e6-96231b3b80d8
2012-07-26 23:10:24 +00:00
Nadav Rotem
2f6622c7bf Fix a bug in FoldSelectOpOp. Bitcast ops may change the number of vector elements, which may disagree with the select condition type.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@158166 91177308-0d34-0410-b5e6-96231b3b80d8
2012-06-07 20:28:57 +00:00
Benjamin Kramer
37fa1c81ac InstCombine: Fix infinite loop when encountering switch on trivial icmp.
The test case feeds the following into InstCombine's visitSelect:
%tobool8 = icmp ne i32 0, 0
%phitmp = select i1 %tobool8, i32 3, i32 0
Then instcombine replaces the right side of the switch with 0, doesn't notice
that nothing changes and tries again indefinitely.

This fixes PR12897.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@157587 91177308-0d34-0410-b5e6-96231b3b80d8
2012-05-28 19:18:16 +00:00
David Blaikie
4d6ccb5f68 More dead code removal (using -Wunreachable-code)
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@148578 91177308-0d34-0410-b5e6-96231b3b80d8
2012-01-20 21:51:11 +00:00
Pete Cooper
4e5a1ab10b Added InstCombine for "select cond, ~cond, x" type patterns
These can be reduced to "~cond & x" or "~cond | x"

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@146624 91177308-0d34-0410-b5e6-96231b3b80d8
2011-12-15 00:56:45 +00:00
Chad Rosier
aab8e28d5e Fix a few more places where TargetData/TargetLibraryInfo is not being passed.
Add FIXMEs to places that are non-trivial to fix.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@145661 91177308-0d34-0410-b5e6-96231b3b80d8
2011-12-02 01:26:24 +00:00
Nick Lewycky
11357d4f40 Add a new icmp+select optz'n. Also shows off the load(cst) folding added in
r140966.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@140969 91177308-0d34-0410-b5e6-96231b3b80d8
2011-10-02 10:37:37 +00:00
Nick Lewycky
267236ade3 Enhance a couple places where we were doing constant folding of instructions,
but not load instructions. Noticed by inspection.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@140966 91177308-0d34-0410-b5e6-96231b3b80d8
2011-10-02 09:12:55 +00:00
Eli Friedman
747032522f Clean up includes of llvm/Analysis/ConstantFolding.h so it's included where it's used and not included where it isn't.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@135628 91177308-0d34-0410-b5e6-96231b3b80d8
2011-07-20 21:57:23 +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
Eli Friedman
00805fae5b PR10180: Fix a instcombine crash with FP vectors.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@133756 91177308-0d34-0410-b5e6-96231b3b80d8
2011-06-23 20:40:23 +00:00
Benjamin Kramer
2c5cc68874 ConstantFoldInstOperands doesn't like compares, hand it off to instsimplify instead.
Fixes PR10040.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@132254 91177308-0d34-0410-b5e6-96231b3b80d8
2011-05-28 10:16:58 +00:00
Benjamin Kramer
17c1bb5d55 InstCombine: Make switch folding with equality compares more aggressive by trying instsimplify on the arm where we know the compared value.
Stuff like "x == y ? y : x&y" now folds into "x&y".

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@132185 91177308-0d34-0410-b5e6-96231b3b80d8
2011-05-27 13:00:16 +00:00
Eli Friedman
976e7e1cc8 Switch more inst insertion in instcombine to IRBuilder.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@131547 91177308-0d34-0410-b5e6-96231b3b80d8
2011-05-18 18:10:28 +00:00
Eli Friedman
1eca76a611 Switch more inst insertion in instcombine to IRBuilder.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@131544 91177308-0d34-0410-b5e6-96231b3b80d8
2011-05-18 17:58:37 +00:00
Eli Friedman
e87ca454ba Switch inst insertion in instcombine transform to IRBuilder.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@131542 91177308-0d34-0410-b5e6-96231b3b80d8
2011-05-18 17:31:55 +00:00
Nick Lewycky
2bf026e375 Remove tabs I accidentally added.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@128413 91177308-0d34-0410-b5e6-96231b3b80d8
2011-03-28 17:48:26 +00:00
Nick Lewycky
675619ca38 Teach the transformation that moves binary operators around selects to preserve
the subclass optional data.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@128388 91177308-0d34-0410-b5e6-96231b3b80d8
2011-03-27 19:51:23 +00:00
Nick Lewycky
98cd75027c Add a small missed optimization: turn X == C ? X : Y into X == C ? C : Y. This
removes one use of X which helps it pass the many hasOneUse() checks.

In my analysis, this turns up very often where X = A >>exact B and that can't be
simplified unless X has one use (except by increasing the lifetime of A which is
generally a performance loss).


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@128373 91177308-0d34-0410-b5e6-96231b3b80d8
2011-03-27 07:30:57 +00:00
Benjamin Kramer
6b4972518c InstCombine: Fix a thinko where transform an icmp under the assumption that it's a zero comparison when it's not.
Fixes PR9454.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@127464 91177308-0d34-0410-b5e6-96231b3b80d8
2011-03-11 11:37:40 +00:00
Nick Lewycky
df3bfae151 Fold select + select where both selects are on the same condition.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@124469 91177308-0d34-0410-b5e6-96231b3b80d8
2011-01-28 03:28:10 +00:00
Tobias Grosser
aa2be84356 Instcombine: Fix pattern where the sext did not dominate the icmp using it
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@123121 91177308-0d34-0410-b5e6-96231b3b80d8
2011-01-09 16:00:11 +00:00
Frits van Bommel
b686eb9186 Fix a bug in r123034 (trying to sext/zext non-integers) and clean up a little.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@123061 91177308-0d34-0410-b5e6-96231b3b80d8
2011-01-08 10:51:36 +00:00
Tobias Grosser
46431d7a93 InstCombine: Match min/max hidden by sext/zext
X = sext x; x >s c ? X : C+1 --> X = sext x; X <s C+1 ? C+1 : X
X = sext x; x <s c ? X : C-1 --> X = sext x; X >s C-1 ? C-1 : X
X = zext x; x >u c ? X : C+1 --> X = zext x; X <u C+1 ? C+1 : X
X = zext x; x <u c ? X : C-1 --> X = zext x; X >u C-1 ? C-1 : X
X = sext x; x >u c ? X : C+1 --> X = sext x; X <u C+1 ? C+1 : X
X = sext x; x <u c ? X : C-1 --> X = sext x; X >u C-1 ? C-1 : X

Instead of calculating this with mixed types promote all to the
larger type. This enables scalar evolution to analyze this
expression. PR8866

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@123034 91177308-0d34-0410-b5e6-96231b3b80d8
2011-01-07 21:33:14 +00:00
Tobias Grosser
8d088bd1e4 Some whitespace fixes
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@123033 91177308-0d34-0410-b5e6-96231b3b80d8
2011-01-07 21:33:13 +00:00
Benjamin Kramer
4ac19470dc InstCombine: creating selects from -1 and 0 is fine, they combine into a sext from i1.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@122453 91177308-0d34-0410-b5e6-96231b3b80d8
2010-12-22 23:12:15 +00:00
Benjamin Kramer
2f7228b80c Generalize the and-icmp-select instcombine further by allowing selects of the form
(x & 2^n) ? 2^m+C : C

we can offset both arms by C to get the "(x & 2^n) ? 2^m : 0" form, optimize the
select to a shift and apply the offset afterwards.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@121609 91177308-0d34-0410-b5e6-96231b3b80d8
2010-12-11 10:49:22 +00:00
Benjamin Kramer
20e3b4b380 Factor the (x & 2^n) ? 2^m : 0 instcombine into its own method and generalize it
to catch cases where n != m with a shift.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@121608 91177308-0d34-0410-b5e6-96231b3b80d8
2010-12-11 09:42:59 +00:00
Dale Johannesen
f514f52790 Teach InstCombine not to use Add and Neg on FP. PR 8490.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@117510 91177308-0d34-0410-b5e6-96231b3b80d8
2010-10-27 23:45:18 +00:00
Owen Anderson
835d425a16 Remove the rest of my instcombine changes. Back to the drawing board on this one.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@108530 91177308-0d34-0410-b5e6-96231b3b80d8
2010-07-16 16:39:00 +00:00
Owen Anderson
11acba0470 Speculatively revert r108429 to fix the clang self-host.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@108436 91177308-0d34-0410-b5e6-96231b3b80d8
2010-07-15 18:18:57 +00:00
Owen Anderson
40bf5e7a68 Per Chris' suggestion, get rid of the select canonicalization and just add
the corresponding or-icmp-and pattern.  This has the added benefit of doing
the matching earlier, and thus being less susceptible to being confused by
earlier transforms.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@108429 91177308-0d34-0410-b5e6-96231b3b80d8
2010-07-15 17:24:23 +00:00
Owen Anderson
96fe621e07 Reapply r108378, with bugfixes, testcase, and improved comment formatting.
This now passes LIT, nighty test, and llvm-gcc bootstrap on my machine.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@108422 91177308-0d34-0410-b5e6-96231b3b80d8
2010-07-15 15:00:23 +00:00
Eli Friedman
5e84e8e52a Speculatively revert r108378; may be causing bootstrap failures.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@108389 91177308-0d34-0410-b5e6-96231b3b80d8
2010-07-15 00:33:00 +00:00
Owen Anderson
bd129a7460 Add instcombine transforms to optimize tests of multiple bits of the same value into a single larger comparison.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@108378 91177308-0d34-0410-b5e6-96231b3b80d8
2010-07-14 23:33:51 +00:00
Benjamin Kramer
1db071f0da Teach instcombine to transform
(X >s -1) ? C1 : C2 and (X <s  0) ? C2 : C1
into ((X >>s 31) & (C2 - C1)) + C1, avoiding the conditional.

This optimization could be extended to take non-const C1 and C2 but we better
stay conservative to avoid code size bloat for now.

for
int sel(int n) {
     return n >= 0 ? 60 : 100;
}

we now generate
  sarl  $31, %edi
  andl  $40, %edi
  leal  60(%rdi), %eax

instead of
  testl %edi, %edi
  movl  $60, %ecx
  movl  $100, %eax
  cmovnsl %ecx, %eax


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@107866 91177308-0d34-0410-b5e6-96231b3b80d8
2010-07-08 11:39:10 +00:00
Chris Lattner
047542669a move some select simplifications out out instcombine into
inst simplify.  No functionality change.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@101873 91177308-0d34-0410-b5e6-96231b3b80d8
2010-04-20 05:32:14 +00:00
Dan Gohman
21dc20cbd6 Don't do (X != Y) ? X : Y -> X for floating-point values; it doesn't
handle NaN properly.

Do (X une Y) ? X : Y  -> X if one of X and Y is not zero.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@96955 91177308-0d34-0410-b5e6-96231b3b80d8
2010-02-23 17:17:57 +00:00
Duncan Sands
b0bc6c361d Uniformize the names of type predicates: rather than having isFloatTy and
isInteger, we now have isFloatTy and isIntegerTy.  Requested by Chris!


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@96223 91177308-0d34-0410-b5e6-96231b3b80d8
2010-02-15 16:12:20 +00:00
Chris Lattner
abb992d6a3 change the canonical form of "cond ? -1 : 0" to be
"sext cond" instead of a select.  This simplifies some instcombine
code, matches the policy for zext (cond ? 1 : 0 -> zext), and allows
us to generate better code for a testcase on ppc.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@94339 91177308-0d34-0410-b5e6-96231b3b80d8
2010-01-24 00:09:49 +00:00
Benjamin Kramer
11acaa374c Convert a ton of simple integer type equality tests to the new predicate.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@92760 91177308-0d34-0410-b5e6-96231b3b80d8
2010-01-05 20:07:06 +00:00
Chris Lattner
1c22c80d71 clean up header.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@92688 91177308-0d34-0410-b5e6-96231b3b80d8
2010-01-05 06:05:07 +00:00
Chris Lattner
c6334b97e1 split select out to its own file.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@92687 91177308-0d34-0410-b5e6-96231b3b80d8
2010-01-05 06:03:12 +00:00