2fd66441c6
Switch more inst insertion in instcombine to IRBuilder.
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llvm-svn: 131547
2011-05-18 18:10:28 +00:00
0b43b9ee98
Switch more inst insertion in instcombine to IRBuilder.
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llvm-svn: 131544
2011-05-18 17:58:37 +00:00
cde9c1628c
Switch inst insertion in instcombine transform to IRBuilder.
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llvm-svn: 131542
2011-05-18 17:31:55 +00:00
728f6260b9
Fix inelegant initialization.
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llvm-svn: 131538
2011-05-18 15:54:26 +00:00
96254a0d53
Start trying to make InstCombine preserve more debug info. The idea here is to set the debug location on the IRBuilder, which will be then right location in most cases. This should magically give many transformations debug locations, and fixing places which are missing a debug location will usually just means changing the code creating it to use the IRBuilder.
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As an example, the change to InstCombineCalls catches a common case where a call to a bitcast of a function is rewritten.
Chris, does this approach look reasonable?
llvm-svn: 131516
2011-05-18 01:28:27 +00:00
b9ed18f2cb
Use ReplaceInstUsesWith instead of replaceAllUsesWith where appropriate in instcombine.
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llvm-svn: 131512
2011-05-18 00:32:01 +00:00
5bd18b6638
X86 pmovsx/pmovzx ignore the upper half of their inputs.
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rdar://problem/6945110
llvm-svn: 131493
2011-05-17 22:13:31 +00:00
66a82b966e
Avoid combining GEPs that might overflow at runtime.
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rdar://problem/9267970
Patch by Julien Lerouge!
llvm-svn: 131339
2011-05-14 05:55:10 +00:00
8a20e66926
PR9838: Fix transform introduced in r127064 to not trigger when only one side of the icmp is an exact shift.
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llvm-svn: 130954
2011-05-05 21:59:18 +00:00
6b699f863f
Remove unused variable.
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llvm-svn: 130705
2011-05-02 18:41:29 +00:00
a3e3699c88
Move some rem transforms out of instcombine and into instsimplify.
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This automagically provides a transform noticed by my super-optimizer
as occurring quite often: "rem x, (select cond, x, 1)" -> 0.
llvm-svn: 130694
2011-05-02 16:27:02 +00:00
9aa91b1f4e
InstCombine: Turn (zext A) udiv (zext B) into (zext (A udiv B)). Same for urem or constant B.
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This obviously helps a lot if the division would be turned into a libcall
(think i64 udiv on i386), but div is also one of the few remaining instructions
on modern CPUs that become more expensive when the bitwidth gets bigger.
This also helps register pressure on i386 when dividing chars, divb needs
two 8-bit parts of a 16 bit register as input where divl uses two registers.
int foo(unsigned char a) { return a/10; }
int bar(unsigned char a, unsigned char b) { return a/b; }
compiles into (x86_64)
_foo:
imull $205, %edi, %eax
shrl $11, %eax
ret
_bar:
movzbl %dil, %eax
divb %sil, %al
movzbl %al, %eax
ret
llvm-svn: 130615
2011-04-30 18:16:07 +00:00
57b3df59b9
Use SimplifyDemandedBits on div instructions.
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This folds away silly stuff like (a&255)/1000 -> 0.
llvm-svn: 130614
2011-04-30 18:16:00 +00:00
f0e3f04470
Balance parentheses.
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llvm-svn: 130489
2011-04-29 08:41:23 +00:00
16f18ed7b5
InstCombine: turn (C1 << A) << C2) into (C1 << C2) << A)
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Fixes PR9809.
llvm-svn: 130485
2011-04-29 08:15:41 +00:00
cf9d1ad62e
We require threse bits to be zero, too.
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This shouldn't happen in practice because the icmp would be a constant.
Add a check so we don't miscompile code if something goes wrong.
llvm-svn: 130446
2011-04-28 21:38:51 +00:00
101720fb58
Fix a comment.
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llvm-svn: 130428
2011-04-28 20:09:57 +00:00
4145c0d3b1
InstCombine: Merge "(trunc x) == C1 & (and x, CA) == C2" into a single and+icmp.
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This happens when GVN widens loads. Part of PR6627.
llvm-svn: 130405
2011-04-28 16:58:40 +00:00
085ad3b81a
Stop trying to have instcombine preserve LCSSA form: this was not
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effective in avoiding recomputation of LCSSA form; the widespread
use of instsimplify (which looks through phi nodes) means it was
not preserving LCSSA form anyway; and instcombine is no longer
scheduled in the middle of the loop passes so this doesn't matter
anymore.
llvm-svn: 130301
2011-04-27 10:55:12 +00:00
1b06c71668
Transform: "icmp eq (trunc (lshr(X, cst1)), cst" to "icmp (and X, mask), cst"
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when X has multiple uses. This is useful for exposing secondary optimizations,
but the X86 backend isn't ready for this when X has a single use. For example,
this can disable load folding.
This is inching towards resolving PR6627.
llvm-svn: 130238
2011-04-26 20:18:20 +00:00
31b106d7dd
some random cleanups, no functionality change.
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llvm-svn: 130237
2011-04-26 20:02:45 +00:00
d6d4f987b4
Rename a misleadingly-named variable.
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llvm-svn: 129644
2011-04-16 14:32:34 +00:00
7d03e9be47
Fix bug when checking phi operands in InstCombiner::visitPHINode(),
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found by code inspection.
llvm-svn: 129641
2011-04-16 14:17:37 +00:00
0ab5e2cded
Fix a ton of comment typos found by codespell. Patch by
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Luis Felipe Strano Moraes!
llvm-svn: 129558
2011-04-15 05:18:47 +00:00
2395626605
Add an instcombine for constructs like a | -(b != c); a select is more
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canonical, and generally leads to better code. Found while looking at
an article about saturating arithmetic.
llvm-svn: 129545
2011-04-14 22:41:27 +00:00
b902f1dd88
Reapply r129401 with patch for clang.
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llvm-svn: 129419
2011-04-13 00:36:11 +00:00
dbfde42468
Revert r129401 for now. Clang is using the old way of doing things.
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llvm-svn: 129403
2011-04-12 22:59:27 +00:00
47c24875a1
Remove the unaligned load intrinsics in favor of using native unaligned loads.
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Now that we have a first-class way to represent unaligned loads, the unaligned
load intrinsics are superfluous.
First part of <rdar://problem/8460511>.
llvm-svn: 129401
2011-04-12 22:46:31 +00:00
7c14a558fe
Don't include Operator.h from InstrTypes.h.
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llvm-svn: 129271
2011-04-11 09:35:34 +00:00
a069c6ce05
InstCombine optimizes gep(bitcast(x)) even when the bitcasts casts away address
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space info. We crash with an assert in this case. This change checks that the
address space of the bitcasted pointer is the same as the gep ptr.
llvm-svn: 128884
2011-04-05 14:29:52 +00:00
50a281a871
While SimplifyDemandedBits constant folds this, we can't rely on it here.
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It's possible to craft an input that hits the recursion limits in a way
that SimplifyDemandedBits doesn't simplify the icmp but ComputeMaskedBits
can infer which bits are zero.
No test case as it depends on too many other things. Fixes PR9609.
llvm-svn: 128777
2011-04-02 18:50:58 +00:00
8b94c295c3
Fix comment.
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llvm-svn: 128745
2011-04-01 22:29:18 +00:00
5cad45307e
Tweaks to the icmp+sext-to-shifts optimization to address Frits' comments:
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- Localize the check if an icmp has one use to a place where we know we're
introducing something that's likely more expensive than a sext from i1.
- Add an assert to make sure a case that would lead to a miscompilation is
folded away earlier.
- Fix a typo.
llvm-svn: 128744
2011-04-01 22:22:11 +00:00
ac2d5657a6
Fix build.
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llvm-svn: 128733
2011-04-01 20:15:16 +00:00
d121765e64
InstCombine: Turn icmp + sext into bitwise/integer ops when the input has only one unknown bit.
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int test1(unsigned x) { return (x&8) ? 0 : -1; }
int test3(unsigned x) { return (x&8) ? -1 : 0; }
before (x86_64):
_test1:
andl $8, %edi
cmpl $1, %edi
sbbl %eax, %eax
ret
_test3:
andl $8, %edi
cmpl $1, %edi
sbbl %eax, %eax
notl %eax
ret
after:
_test1:
shrl $3, %edi
andl $1, %edi
leal -1(%rdi), %eax
ret
_test3:
shll $28, %edi
movl %edi, %eax
sarl $31, %eax
ret
llvm-svn: 128732
2011-04-01 20:09:10 +00:00
398b8c5faf
InstCombine: Move (sext icmp) transforms into their own method. No intended functionality change.
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llvm-svn: 128731
2011-04-01 20:09:03 +00:00
d74b72b8a9
Instcombile optimization: extractelement(cast) -> cast(extractelement)
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llvm-svn: 128683
2011-03-31 22:57:29 +00:00
5291054ef1
InstCombine: APFloat can't perform arithmetic on PPC double doubles, don't even try.
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Thanks Eli!
llvm-svn: 128676
2011-03-31 21:35:49 +00:00
be209ab8a2
InstCombine: Fix transform to use the swapped predicate.
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Thanks Frits!
llvm-svn: 128628
2011-03-31 10:46:03 +00:00
d159d94644
InstCombine: fold fcmp (fneg x), (fneg y) -> fcmp x, y
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llvm-svn: 128627
2011-03-31 10:12:22 +00:00
a8c5d0872d
InstCombine: fold fcmp pred (fneg x), C -> fcmp swap(pred) x, -C
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llvm-svn: 128626
2011-03-31 10:12:15 +00:00
cbb18e91a8
InstCombine: Shrink "fcmp (fpext x), C" to "fcmp x, C" if C can be losslessly converted to the type of x.
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Fixes PR9592.
llvm-svn: 128625
2011-03-31 10:12:07 +00:00
2ccfbc8b71
InstCombine: fold fcmp (fpext x), (fpext y) -> fcmp x, y.
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llvm-svn: 128624
2011-03-31 10:11:58 +00:00
8564e0de96
InstCombine: If the divisor of an fdiv has an exact inverse, turn it into an fmul.
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Fixes PR9587.
llvm-svn: 128546
2011-03-30 15:42:35 +00:00
52131344a2
Remove PHINode::reserveOperandSpace(). Instead, add a parameter to
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PHINode::Create() giving the (known or expected) number of operands.
llvm-svn: 128537
2011-03-30 11:28:46 +00:00
e0938d8a87
(Almost) always call reserveOperandSpace() on newly created PHINodes.
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llvm-svn: 128535
2011-03-30 11:19:20 +00:00
272f2b0044
InstCombine: Add a few missing combines for ANDs and ORs of sign bit tests.
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On x86 we now compile "if (a < 0 && b < 0)" into
testl %edi, %esi
js IF.THEN
llvm-svn: 128496
2011-03-29 22:06:41 +00:00
ebc2f3a68c
Remove tabs I accidentally added.
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llvm-svn: 128413
2011-03-28 17:48:26 +00:00
1c83965f5a
Make more use of PHINode::getNumIncomingValues().
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llvm-svn: 128406
2011-03-28 13:03:10 +00:00
d14d991bf7
Add some debug output when -instcombine uses RAUW. This can make debug output for those cases much clearer since without this it only showed that the original instruction was removed, not what it was replaced with.
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llvm-svn: 128399
2011-03-27 23:32:31 +00:00
Eli Friedman