Commit Graph

185 Commits

Author SHA1 Message Date
David Majnemer b889e405eb InstCombine: Optimize (1 << X) Pred CstP2 to X Pred Log2(CstP2)
We may, after other optimizations, find ourselves with IR that looks
like:

  %shl = shl i32 1, %y
  %cmp = icmp ult i32 %shl, 32

Instead, we should just compare the shift count:

  %cmp = icmp ult i32 %y, 5

llvm-svn: 185242
2013-06-28 23:42:03 +00:00
Michael Gottesman 79b0967548 Revert "Revert "[APFloat] Removed APFloat constructor which initialized to either zero/NaN but allowed you to arbitrarily set the category of the float.""
This reverts commit r185099.

Looks like both the ppc-64 and mips bots are still failing after I reverted this
change.

Since:

1. The mips bot always performs a clean build,
2. The ppc64-bot failed again after a clean build (I asked the ppc-64
maintainers to clean the bot which they did... Thanks Will!),

I think it is safe to assume that this change was not the cause of the failures
that said builders were seeing. Thus I am recomitting.

llvm-svn: 185111
2013-06-27 21:58:19 +00:00
Michael Gottesman ccaf3321f1 Revert "[APFloat] Removed APFloat constructor which initialized to either zero/NaN but allowed you to arbitrarily set the category of the float."
This reverts commit r185095. This is causing a FileCheck failure on
the 3dnow intrinsics on at least the mips/ppc bots but not on the x86
bots.

Reverting while I figure out what is going on.

llvm-svn: 185099
2013-06-27 20:40:11 +00:00
Michael Gottesman 03255a1675 [APFloat] Removed APFloat constructor which initialized to either zero/NaN but allowed you to arbitrarily set the category of the float.
The category which an APFloat belongs to should be dependent on the
actual value that the APFloat has, not be arbitrarily passed in by the
user. This will prevent inconsistency bugs where the category and the
actual value in APFloat differ.

I also fixed up all of the references to this constructor (which were
only in LLVM).

llvm-svn: 185095
2013-06-27 19:50:52 +00:00
Jakub Staszak bddea11bc5 Re-apply "Use IRBuilder instead of ConstantInt methods." with the fixed issues.
llvm-svn: 183439
2013-06-06 20:18:46 +00:00
Rafael Espindola a7bbc0b740 Revert "Use IRBuilder instead of ConstantInt methods. It simplifies code a little bit."
This reverts commit 183328. It caused pr16244 and broke the bots.

llvm-svn: 183422
2013-06-06 17:03:05 +00:00
Jakub Staszak 2f390b755a Use IRBuilder instead of ConstantInt methods. It simplifies code a little bit.
llvm-svn: 183328
2013-06-05 18:27:02 +00:00
David Majnemer 1a08accbb7 Simplify (A & ~B) in icmp if A is a power of 2
The transform will execute like so:
(A & ~B) == 0 --> (A & B) != 0
(A & ~B) != 0 --> (A & B) == 0

llvm-svn: 179386
2013-04-12 17:25:07 +00:00
David Majnemer b81cd63c4b Optimize icmp involving addition better
Allows LLVM to optimize sequences like the following:

%add = add nsw i32 %x, 1
%cmp = icmp sgt i32 %add, %y

into:

%cmp = icmp sge i32 %x, %y

as well as:

%add1 = add nsw i32 %x, 20
%add2 = add nsw i32 %y, 57
%cmp = icmp sge i32 %add1, %add2

into:

%add = add nsw i32 %y, 37
%cmp = icmp sle i32 %cmp, %x

llvm-svn: 179316
2013-04-11 20:05:46 +00:00
Jim Grosbach bdbd73460c Tidy up a bit. No functional change.
llvm-svn: 178915
2013-04-05 21:20:12 +00:00
Arnaud A. de Grandmaison 3ee88e8a77 Address issues found by Duncan during post-commit review of r177856.
llvm-svn: 177863
2013-03-25 11:47:38 +00:00
Arnaud A. de Grandmaison 9c383d68cf InstCombine: simplify comparisons to zero of (shl %x, Cst) or (mul %x, Cst)
This simplification happens at 2 places :
 - using the nsw attribute when the shl / mul is used by a sign test
 - when the shl / mul is compared for (in)equality to zero

llvm-svn: 177856
2013-03-25 09:48:49 +00:00
Arnaud A. de Grandmaison f364bc63e7 InstCombine: Improve the result bitvect type when folding (cmp pred (load (gep GV, i)) C) to a bit test.
The original code used i32, and i64 if legal. This introduced unneeded
casts when they aren't legal, or when the index variable i has another
type. In order of preference: try to use i's type; use the smallest
fitting legal type (using an added DataLayout method); default to i32.
A testcase checks that this works when the index gep operand is i16.

Patch by : Ahmed Bougacha <ahmed.bougacha@gmail.com>
Reviewed by : Duncan

llvm-svn: 177712
2013-03-22 08:25:01 +00:00
Arnaud A. de Grandmaison 7153305b92 Fix a performance regression when combining to smaller types in icmp (shl %v, C1), C2 :
Only combine when the shl is only used by the icmp

llvm-svn: 176950
2013-03-13 14:40:37 +00:00
Arnaud A. de Grandmaison 1fd843eee7 Fix refactoring mistake in "Teach InstCombine to work with smaller legal types..."
llvm-svn: 175273
2013-02-15 15:18:17 +00:00
Arnaud A. de Grandmaison 61c167c62b Teach InstCombine to work with smaller legal types in icmp (shl %v, C1), C2
It enables to work with a smaller constant, which is target friendly for those which can compare to immediates.
It also avoids inserting a shift in favor of a trunc, which can be free on some targets.

This used to work until LLVM-3.1, but regressed with the 3.2 release.

llvm-svn: 175270
2013-02-15 14:35:47 +00:00
Chandler Carruth 9fb823bbd4 Move all of the header files which are involved in modelling the LLVM IR
into their new header subdirectory: include/llvm/IR. This matches the
directory structure of lib, and begins to correct a long standing point
of file layout clutter in LLVM.

There are still more header files to move here, but I wanted to handle
them in separate commits to make tracking what files make sense at each
layer easier.

The only really questionable files here are the target intrinsic
tablegen files. But that's a battle I'd rather not fight today.

I've updated both CMake and Makefile build systems (I think, and my
tests think, but I may have missed something).

I've also re-sorted the includes throughout the project. I'll be
committing updates to Clang, DragonEgg, and Polly momentarily.

llvm-svn: 171366
2013-01-02 11:36:10 +00:00
Paul Redmond 5917f4c715 Transform (x&C)>V into (x&C)!=0 where possible
When the least bit of C is greater than V, (x&C) must be greater than V
if it is not zero, so the comparison can be simplified.

Although this was suggested in Target/X86/README.txt, it benefits any
architecture with a directly testable form of AND.

Patch by Kevin Schoedel

llvm-svn: 170576
2012-12-19 19:47:13 +00:00
NAKAMURA Takumi 38d2b2442f Revert r170020, "Simplify negated bit test", for now.
This assumes (1 << n) is always not zero. Consider n is greater than word size.
Although I know it is undefined, this transforms undefined behavior hidden.

This led clang unexpected behavior with some failures. I will investigate to fix undefined shl in clang.

llvm-svn: 170128
2012-12-13 14:28:16 +00:00
Rafael Espindola a2c107e661 Missed these calls from the previous rename somehow.
llvm-svn: 170094
2012-12-13 03:42:31 +00:00
David Majnemer 5226aa94ce Simplify negated bit test
llvm-svn: 170020
2012-12-12 20:48:54 +00:00
Chandler Carruth ed0881b2a6 Use the new script to sort the includes of every file under lib.
Sooooo many of these had incorrect or strange main module includes.
I have manually inspected all of these, and fixed the main module
include to be the nearest plausible thing I could find. If you own or
care about any of these source files, I encourage you to take some time
and check that these edits were sensible. I can't have broken anything
(I strictly added headers, and reordered them, never removed), but they
may not be the headers you'd really like to identify as containing the
API being implemented.

Many forward declarations and missing includes were added to a header
files to allow them to parse cleanly when included first. The main
module rule does in fact have its merits. =]

llvm-svn: 169131
2012-12-03 16:50:05 +00:00
Duncan Sands d7d8c09b93 Make this easier to understand, as suggested by Chandler.
llvm-svn: 168196
2012-11-16 20:53:08 +00:00
Duncan Sands 1d3acddf0e Fix PR14361: wrong simplification of A+B==B+A. You may think that the old logic
replaced by this patch is equivalent to the new logic, but you'd be wrong, and
that's exactly where the bug was.  There's a similar bug in instsimplify which
manifests itself as instsimplify failing to simplify this, rather than doing it
wrong, see next commit.

llvm-svn: 168181
2012-11-16 18:55:49 +00:00
Chandler Carruth 5da3f0512e Revert the majority of the next patch in the address space series:
r165941: Resubmit the changes to llvm core to update the functions to
         support different pointer sizes on a per address space basis.

Despite this commit log, this change primarily changed stuff outside of
VMCore, and those changes do not carry any tests for correctness (or
even plausibility), and we have consistently found questionable or flat
out incorrect cases in these changes. Most of them are probably correct,
but we need to devise a system that makes it more clear when we have
handled the address space concerns correctly, and ideally each pass that
gets updated would receive an accompanying test case that exercises that
pass specificaly w.r.t. alternate address spaces.

However, from this commit, I have retained the new C API entry points.
Those were an orthogonal change that probably should have been split
apart, but they seem entirely good.

In several places the changes were very obvious cleanups with no actual
multiple address space code added; these I have not reverted when
I spotted them.

In a few other places there were merge conflicts due to a cleaner
solution being implemented later, often not using address spaces at all.
In those cases, I've preserved the new code which isn't address space
dependent.

This is part of my ongoing effort to clean out the partial address space
code which carries high risk and low test coverage, and not likely to be
finished before the 3.2 release looms closer. Duncan and I would both
like to see the above issues addressed before we return to these
changes.

llvm-svn: 167222
2012-11-01 09:14:31 +00:00
Chandler Carruth 7ec5085e01 Revert the series of commits starting with r166578 which introduced the
getIntPtrType support for multiple address spaces via a pointer type,
and also introduced a crasher bug in the constant folder reported in
PR14233.

These commits also contained several problems that should really be
addressed before they are re-committed. I have avoided reverting various
cleanups to the DataLayout APIs that are reasonable to have moving
forward in order to reduce the amount of churn, and minimize the number
of commits that were reverted. I've also manually updated merge
conflicts and manually arranged for the getIntPtrType function to stay
in DataLayout and to be defined in a plausible way after this revert.

Thanks to Duncan for working through this exact strategy with me, and
Nick Lewycky for tracking down the really annoying crasher this
triggered. (Test case to follow in its own commit.)

After discussing with Duncan extensively, and based on a note from
Micah, I'm going to continue to back out some more of the more
problematic patches in this series in order to ensure we go into the
LLVM 3.2 branch with a reasonable story here. I'll send a note to
llvmdev explaining what's going on and why.

Summary of reverted revisions:

r166634: Fix a compiler warning with an unused variable.
r166607: Add some cleanup to the DataLayout changes requested by
         Chandler.
r166596: Revert "Back out r166591, not sure why this made it through
         since I cancelled the command. Bleh, sorry about this!
r166591: Delete a directory that wasn't supposed to be checked in yet.
r166578: Add in support for getIntPtrType to get the pointer type based
         on the address space.
llvm-svn: 167221
2012-11-01 08:07:29 +00:00
Ulrich Weigand 6a9bb51a8d Enable some additional constant folding for PPCDoubleDouble.
This fixes Clang :: CodeGen/complex-builtints.c on PowerPC.

llvm-svn: 167013
2012-10-30 12:33:18 +00:00
Micah Villmow bf3eeb2dfc Add some cleanup to the DataLayout changes requested by Chandler.
llvm-svn: 166607
2012-10-24 18:36:13 +00:00
Micah Villmow 12d9127833 Add in support for getIntPtrType to get the pointer type based on the address space.
This checkin also adds in some tests that utilize these paths and updates some of the
clients.

llvm-svn: 166578
2012-10-24 15:52:52 +00:00
Micah Villmow 4bb926d91d Resubmit the changes to llvm core to update the functions to support different pointer sizes on a per address space basis.
llvm-svn: 165941
2012-10-15 16:24:29 +00:00
Micah Villmow 0c61134d8d Revert 165732 for further review.
llvm-svn: 165747
2012-10-11 21:27:41 +00:00
Micah Villmow 083189730e Add in the first iteration of support for llvm/clang/lldb to allow variable per address space pointer sizes to be optimized correctly.
llvm-svn: 165726
2012-10-11 17:21:41 +00:00
Micah Villmow cdfe20b97f Move TargetData to DataLayout.
llvm-svn: 165402
2012-10-08 16:38:25 +00:00
Benjamin Kramer 9d03242fcf InstCombine: Fix a crasher when encountering a function pointer.
llvm-svn: 162180
2012-08-18 22:04:34 +00:00
Benjamin Kramer 9282aef86d Remove overly conservative hasOneUse check, this always expands into a single IR instruction.
llvm-svn: 162175
2012-08-18 20:24:19 +00:00
Benjamin Kramer 8c2a733c55 InstCombine: Add a couple of fabs identities for comparing with 0.0.
llvm-svn: 162174
2012-08-18 20:06:47 +00:00
Bob Wilson 61f3ad5759 Fix a serious typo in InstCombine's optimization of comparisons.
An unsigned value converted to floating-point will always be greater than
a negative constant.  Unfortunately InstCombine reversed the check so that
unsigned values were being optimized to always be greater than all positive
floating-point constants.  <rdar://problem/12029145>

llvm-svn: 161452
2012-08-07 22:35:16 +00:00
Benjamin Kramer 2150145ae4 InstCombine: factor code better.
No functionality change.

llvm-svn: 158301
2012-06-11 08:01:25 +00:00
Benjamin Kramer 8b8a76974f InstCombine: Turn (zext A) == (B & (1<<X)-1) into A == (trunc B), narrowing the compare.
This saves a cast, and zext is more expensive on platforms with subreg support
than trunc is. This occurs in the BSD implementation of memchr(3), see PR12750.
On the synthetic benchmark from that bug stupid_memchr and bsd_memchr have the
same performance now when not inlining either function.

stupid_memchr: 323.0us
bsd_memchr: 321.0us
memchr: 479.0us

where memchr is the llvm-gcc compiled bsd_memchr from osx lion's libc. When
inlining is enabled bsd_memchr still regresses down to llvm-gcc memchr time,
I haven't fully understood the issue yet, something is grossly mangling the
loop after inlining.

llvm-svn: 158297
2012-06-10 20:35:00 +00:00
Eli Friedman e0a64d83fc Fix a minor logic mistake transforming compares in instcombine. PR12514.
llvm-svn: 156600
2012-05-11 01:32:59 +00:00
Rafael Espindola ba0a6cabb8 Always compute all the bits in ComputeMaskedBits.
This allows us to keep passing reduced masks to SimplifyDemandedBits, but
know about all the bits if SimplifyDemandedBits fails. This allows instcombine
to simplify cases like the one in the included testcase.

llvm-svn: 154011
2012-04-04 12:51:34 +00:00
Benjamin Kramer c7a22fe76b Fix unsigned off-by-one in comment.
llvm-svn: 151056
2012-02-21 13:40:06 +00:00
Benjamin Kramer 6ee8690aa5 InstCombine: Don't transform a signed icmp of two GEPs into a signed compare of the indices.
This transformation is not safe in some pathological cases (signed icmp of pointers should be an
extremely rare thing, but it's valid IR!). Add an explanatory comment.

Kudos to Duncan for pointing out this edge case (and not giving up explaining it until I finally got it).

llvm-svn: 151055
2012-02-21 13:31:09 +00:00
Benjamin Kramer ac8ecc4e7e InstCombine: Removing the base from the address calculation is only safe when the GEPs are inbounds.
llvm-svn: 150978
2012-02-20 18:45:10 +00:00
Benjamin Kramer 7adb189538 InstCombine: When comparing two GEPs that were derived from the same base pointer but use different types, expand the offset calculation and to the compare on the offset if profitable.
This came up in SmallVector code.

llvm-svn: 150962
2012-02-20 15:07:47 +00:00
Devang Patel 698452bc7e Check against umin while converting fcmp into an icmp.
llvm-svn: 150425
2012-02-13 23:05:18 +00:00
Chris Lattner fe741769dd enhance logic to support ConstantDataArray.
llvm-svn: 149340
2012-01-31 02:55:06 +00:00
Dan Gohman 518cda42b9 The powers that be have decided that LLVM IR should now support 16-bit
"half precision" floating-point with a first-class type.

This patch adds basic IR support (but not codegen support).

llvm-svn: 146786
2011-12-17 00:04:22 +00:00
Chad Rosier 43a33066b4 Fix a few more places where TargetData/TargetLibraryInfo is not being passed.
Add FIXMEs to places that are non-trivial to fix.

llvm-svn: 145661
2011-12-02 01:26:24 +00:00
Pete Cooper fdddc27143 Improved fix for abs(val) != 0 to check other similar case. Also fixed style issues and confusing comment
llvm-svn: 145618
2011-12-01 19:13:26 +00:00
Pete Cooper bc5c524b71 Added instcombine pattern to spot comparing -val or val against 0.
(val != 0) == (-val != 0) so "abs(val) != 0" becomes "val != 0"

Fixes <rdar://problem/10482509>

llvm-svn: 145563
2011-12-01 03:58:40 +00:00
Eli Friedman b3f9b0676a Add a missing safety check to ProcessUGT_ADDCST_ADD. Fixes PR11438.
llvm-svn: 145316
2011-11-28 23:32:19 +00:00
Jim Grosbach 011dafba61 Don't modify constant in-place.
llvm-svn: 140875
2011-09-30 19:58:46 +00:00
Jim Grosbach 24ff834671 float comparison to double 'zero' constant can just be a float 'zero.'
InstCombine was incorrectly considering the conversion of the constant
zero to be unsafe.

We want to transform:
define float @bar(float %x) nounwind readnone optsize ssp {
  %conv = fpext float %x to double
  %cmp = fcmp olt double %conv, 0.000000e+00
  %conv1 = zext i1 %cmp to i32
  %conv2 = sitofp i32 %conv1 to float
  ret float %conv2
}

Into:
define float @bar(float %x) nounwind readnone optsize ssp {
  %cmp = fcmp olt float %x, 0.000000e+00   ; <---- This
  %conv1 = zext i1 %cmp to i32
  %conv2 = sitofp i32 %conv1 to float
  ret float %conv2
}


rdar://10215914

llvm-svn: 140869
2011-09-30 18:45:50 +00:00
Jim Grosbach 129c52af18 Tidy up. Trailing whitespace.
llvm-svn: 140865
2011-09-30 18:09:53 +00:00
Benjamin Kramer 547b6c5ecd Stop emitting instructions with the name "tmp" they eat up memory and have to be uniqued, without any benefit.
If someone prefers %tmp42 to %42, run instnamer.

llvm-svn: 140634
2011-09-27 20:39:19 +00:00
Eli Friedman 911e12f505 Clean up includes of llvm/Analysis/ConstantFolding.h so it's included where it's used and not included where it isn't.
llvm-svn: 135628
2011-07-20 21:57:23 +00:00
Chris Lattner 229907cd11 land David Blaikie's patch to de-constify Type, with a few tweaks.
llvm-svn: 135375
2011-07-18 04:54:35 +00:00
Chris Lattner b1a1512119 start using the new helper methods a bit.
llvm-svn: 135251
2011-07-15 06:08:15 +00:00
Benjamin Kramer e6e1933f31 Change Intrinsic::getDeclaration and friends to take an ArrayRef.
llvm-svn: 135154
2011-07-14 17:45:39 +00:00
Jay Foad 57aa636794 Convert InsertValueInst and ExtractValueInst APIs to use ArrayRef.
llvm-svn: 135040
2011-07-13 10:26:04 +00:00
Jay Foad b804a2b751 Second attempt at de-constifying LLVM Types in FunctionType::get(),
StructType::get() and TargetData::getIntPtrType().

llvm-svn: 134982
2011-07-12 14:06:48 +00:00
Bill Wendling a78cd228c2 Revert r134893 and r134888 (and related patches in other trees). It was causing
an assert on Darwin llvm-gcc builds.

Assertion failed: (castIsValid(op, S, Ty) && "Invalid cast!"), function Create, file /Users/buildslave/zorg/buildbot/smooshlab/slave-0.8/build.llvm-gcc-i386-darwin9-RA/llvm.src/lib/VMCore/Instructions.cpp, li\
ne 2067.
etc.

http://smooshlab.apple.com:8013/builders/llvm-gcc-i386-darwin9-RA/builds/2354

--- Reverse-merging r134893 into '.':
U    include/llvm/Target/TargetData.h
U    include/llvm/DerivedTypes.h
U    tools/bugpoint/ExtractFunction.cpp
U    unittests/Support/TypeBuilderTest.cpp
U    lib/Target/ARM/ARMGlobalMerge.cpp
U    lib/Target/TargetData.cpp
U    lib/VMCore/Constants.cpp
U    lib/VMCore/Type.cpp
U    lib/VMCore/Core.cpp
U    lib/Transforms/Utils/CodeExtractor.cpp
U    lib/Transforms/Instrumentation/ProfilingUtils.cpp
U    lib/Transforms/IPO/DeadArgumentElimination.cpp
U    lib/CodeGen/SjLjEHPrepare.cpp
--- Reverse-merging r134888 into '.':
G    include/llvm/DerivedTypes.h
U    include/llvm/Support/TypeBuilder.h
U    include/llvm/Intrinsics.h
U    unittests/Analysis/ScalarEvolutionTest.cpp
U    unittests/ExecutionEngine/JIT/JITTest.cpp
U    unittests/ExecutionEngine/JIT/JITMemoryManagerTest.cpp
U    unittests/VMCore/PassManagerTest.cpp
G    unittests/Support/TypeBuilderTest.cpp
U    lib/Target/MBlaze/MBlazeIntrinsicInfo.cpp
U    lib/Target/Blackfin/BlackfinIntrinsicInfo.cpp
U    lib/VMCore/IRBuilder.cpp
G    lib/VMCore/Type.cpp
U    lib/VMCore/Function.cpp
G    lib/VMCore/Core.cpp
U    lib/VMCore/Module.cpp
U    lib/AsmParser/LLParser.cpp
U    lib/Transforms/Utils/CloneFunction.cpp
G    lib/Transforms/Utils/CodeExtractor.cpp
U    lib/Transforms/Utils/InlineFunction.cpp
U    lib/Transforms/Instrumentation/GCOVProfiling.cpp
U    lib/Transforms/Scalar/ObjCARC.cpp
U    lib/Transforms/Scalar/SimplifyLibCalls.cpp
U    lib/Transforms/Scalar/MemCpyOptimizer.cpp
G    lib/Transforms/IPO/DeadArgumentElimination.cpp
U    lib/Transforms/IPO/ArgumentPromotion.cpp
U    lib/Transforms/InstCombine/InstCombineCompares.cpp
U    lib/Transforms/InstCombine/InstCombineAndOrXor.cpp
U    lib/Transforms/InstCombine/InstCombineCalls.cpp
U    lib/CodeGen/DwarfEHPrepare.cpp
U    lib/CodeGen/IntrinsicLowering.cpp
U    lib/Bitcode/Reader/BitcodeReader.cpp

llvm-svn: 134949
2011-07-12 01:15:52 +00:00
Jay Foad 56cc1530ee De-constify Types in FunctionType::get().
llvm-svn: 134888
2011-07-11 07:56:41 +00:00
Benjamin Kramer 9eca5feff1 PR10267: Don't combine an equality compare with an AND into an inequality compare when the AND has more than one use.
This can pessimize code, inequalities are generally more expensive.

llvm-svn: 134379
2011-07-04 20:16:36 +00:00
Benjamin Kramer c970849ea0 InstCombine: Fold A-b == C --> b == A-C if A and C are constants.
The backend already knew this trick.

llvm-svn: 132915
2011-06-13 15:24:24 +00:00
Benjamin Kramer 91f914ce21 InstCombine: Shrink ((zext X) & C1) == C2 to fold away the cast if the "zext" and the "and" have one use.
llvm-svn: 132897
2011-06-12 22:48:00 +00:00
Benjamin Kramer 35159c114c Simplify code. No functionality changes, name changes aside.
llvm-svn: 132896
2011-06-12 22:47:53 +00:00
Eli Friedman 865866e7fe PR9998: ashr exact %x, 31 is not equivalent to sdiv exact %x, -2147483648.
llvm-svn: 132097
2011-05-25 23:26:20 +00:00
Eli Friedman 1754a25977 More instcombine simplifications towards better debug locations.
llvm-svn: 131596
2011-05-18 23:11:30 +00:00
Stuart Hastings 66a82b966e Avoid combining GEPs that might overflow at runtime.
rdar://problem/9267970

Patch by Julien Lerouge!

llvm-svn: 131339
2011-05-14 05:55:10 +00:00
Eli Friedman 8a20e66926 PR9838: Fix transform introduced in r127064 to not trigger when only one side of the icmp is an exact shift.
llvm-svn: 130954
2011-05-05 21:59:18 +00:00
Chris Lattner 1b06c71668 Transform: "icmp eq (trunc (lshr(X, cst1)), cst" to "icmp (and X, mask), cst"
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
Chris Lattner 31b106d7dd some random cleanups, no functionality change.
llvm-svn: 130237
2011-04-26 20:02:45 +00:00
Chris Lattner 0ab5e2cded 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
Benjamin Kramer 5291054ef1 InstCombine: APFloat can't perform arithmetic on PPC double doubles, don't even try.
Thanks Eli!

llvm-svn: 128676
2011-03-31 21:35:49 +00:00
Benjamin Kramer be209ab8a2 InstCombine: Fix transform to use the swapped predicate.
Thanks Frits!

llvm-svn: 128628
2011-03-31 10:46:03 +00:00
Benjamin Kramer d159d94644 InstCombine: fold fcmp (fneg x), (fneg y) -> fcmp x, y
llvm-svn: 128627
2011-03-31 10:12:22 +00:00
Benjamin Kramer a8c5d0872d InstCombine: fold fcmp pred (fneg x), C -> fcmp swap(pred) x, -C
llvm-svn: 128626
2011-03-31 10:12:15 +00:00
Benjamin Kramer cbb18e91a8 InstCombine: Shrink "fcmp (fpext x), C" to "fcmp x, C" if C can be losslessly converted to the type of x.
Fixes PR9592.

llvm-svn: 128625
2011-03-31 10:12:07 +00:00
Benjamin Kramer 2ccfbc8b71 InstCombine: fold fcmp (fpext x), (fpext y) -> fcmp x, y.
llvm-svn: 128624
2011-03-31 10:11:58 +00:00
Nick Lewycky afc8098c9e Reorder comments to put them the right way around.
llvm-svn: 127220
2011-03-08 06:29:47 +00:00
Nick Lewycky 92db8e8e39 ConstantInt has some getters which return ConstantInt's or ConstantVector's of
the value splatted into every element. Extend this to getTrue and getFalse which
by providing new overloads that take Types that are either i1 or <N x i1>. Use
it in InstCombine to add vector support to some code, fixing PR8469!

llvm-svn: 127116
2011-03-06 03:36:19 +00:00
Nick Lewycky 9719a719c7 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!

llvm-svn: 127064
2011-03-05 05:19:11 +00:00
Nick Lewycky 25cc338d88 Try once again to optimize "icmp (srem X, Y), Y" by turning the comparison into
true/false or "icmp slt/sge Y, 0".

llvm-svn: 127063
2011-03-05 04:28:48 +00:00
Nick Lewycky 66f4f22f7b 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 174a705497 Teach InstCombine to fold "(shr exact X, Y) == 0" --> X == 0, fixing #1 from
PR9343.

llvm-svn: 126643
2011-02-28 08:31:40 +00:00
Nick Lewycky 6b445419b0 The sign of an srem instruction is the sign of its dividend (the first
argument), regardless of the divisor. Teach instcombine about this and fix
test7 in PR9343!

llvm-svn: 126635
2011-02-28 06:20:05 +00:00
Duncan Sands 84653b3674 Add some transforms of the kind X-Y>X -> 0>Y which are valid when there is no
overflow.  These subsume some existing equality transforms, so zap those.

llvm-svn: 125843
2011-02-18 16:25:37 +00:00
Duncan Sands e522001171 Transform "A + B >= A + C" into "B >= C" if the adds do not wrap. Likewise for some
variations (some of these were already present so I unified the code).  Spotted by my
auto-simplifier as occurring a lot.

llvm-svn: 125734
2011-02-17 07:46:37 +00:00
Chris Lattner 9bd7fdff58 remove a now-unneccesary cast.
llvm-svn: 125464
2011-02-13 18:30:09 +00:00
Chris Lattner 43273affb9 implement instcombine folding for things like (x >> c) < 42.
We were previously simplifying divisions, but not right shifts!

llvm-svn: 125454
2011-02-13 08:07:21 +00:00
Chris Lattner d369f575d7 refactor some code out into a helper method.
llvm-svn: 125451
2011-02-13 07:43:07 +00:00
Benjamin Kramer 1800d823de Also fold (A+B) == A -> B == 0 when the add is commuted.
llvm-svn: 125411
2011-02-11 21:46:48 +00:00
Chris Lattner 98457101fc Enhance the "compare with shift" and "compare with div"
optimizations to be much more aggressive in the face of
exact/nsw/nuw div and shifts.  For example, these (which
are the same except the first is 'exact' sdiv:

define i1 @sdiv_icmp4_exact(i64 %X) nounwind {
  %A = sdiv exact i64 %X, -5   ; X/-5 == 0 --> x == 0
  %B = icmp eq i64 %A, 0
  ret i1 %B
}

define i1 @sdiv_icmp4(i64 %X) nounwind {
  %A = sdiv i64 %X, -5   ; X/-5 == 0 --> x == 0
  %B = icmp eq i64 %A, 0
  ret i1 %B
}

compile down to:

define i1 @sdiv_icmp4_exact(i64 %X) nounwind {
  %1 = icmp eq i64 %X, 0
  ret i1 %1
}

define i1 @sdiv_icmp4(i64 %X) nounwind {
  %X.off = add i64 %X, 4
  %1 = icmp ult i64 %X.off, 9
  ret i1 %1
}

This happens when you do something like:
  (ptr1-ptr2) == 42

where the pointers are pointers to non-unit types.

llvm-svn: 125266
2011-02-10 05:23:05 +00:00
Anders Carlsson f23a6da271 Recognize and simplify
(A+B) == A  ->  B == 0
A == (A+B)  ->  B == 0

llvm-svn: 124567
2011-01-30 22:01:13 +00:00
Duncan Sands 8fb2c3827c 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.

llvm-svn: 123911
2011-01-20 13:21:55 +00:00
Chris Lattner ea7131a062 remove the AllowAggressive argument to FoldOpIntoPhi. It is forced to false in the
first line of the function because it isn't a good idea, even for compares.

llvm-svn: 123566
2011-01-16 05:14:26 +00:00
Chris Lattner 497459d5fd fix typo
llvm-svn: 123516
2011-01-15 05:42:47 +00:00
Chris Lattner f3c4eefff8 Catch ~x < cst just like ~x < ~y, we currently handle this through
means that are about to disappear.

llvm-svn: 123515
2011-01-15 05:41:33 +00:00