Commit Graph

283 Commits

Author SHA1 Message Date
Simon Pilgrim
c365e7e2b5 Remove TargetInstrInfo::canFoldMemoryOperand
canFoldMemoryOperand is not actually used anywhere in the codebase - all existing users instead call foldMemoryOperand directly when they wish to fold and can correctly deduce what they need from the return value. 

This patch removes the canFoldMemoryOperand base function and the target implementations; only x86 had a real (bit-rotted) implementation, although AMDGPU had a preparatory stub that had never needed to be completed.

Differential Revision: http://reviews.llvm.org/D11331

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@242638 91177308-0d34-0410-b5e6-96231b3b80d8
2015-07-19 10:50:53 +00:00
Alexander Kornienko
cd52a7a381 Revert r240137 (Fixed/added namespace ending comments using clang-tidy. NFC)
Apparently, the style needs to be agreed upon first.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@240390 91177308-0d34-0410-b5e6-96231b3b80d8
2015-06-23 09:49:53 +00:00
Sanjay Patel
30c3b2a4c2 name change: hasPattern() -> getMachineCombinerPatterns() ; NFC
This was suggested as part of D10460, but it's independent of
any functional change.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@240192 91177308-0d34-0410-b5e6-96231b3b80d8
2015-06-19 23:21:42 +00:00
Alexander Kornienko
cf0db29df2 Fixed/added namespace ending comments using clang-tidy. NFC
The patch is generated using this command:

tools/clang/tools/extra/clang-tidy/tool/run-clang-tidy.py -fix \
  -checks=-*,llvm-namespace-comment -header-filter='llvm/.*|clang/.*' \
  llvm/lib/


Thanks to Eugene Kosov for the original patch!



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@240137 91177308-0d34-0410-b5e6-96231b3b80d8
2015-06-19 15:57:42 +00:00
Sanjoy Das
a1e554d253 [TargetInstrInfo] Add new hook: AnalyzeBranchPredicate.
Summary:
NFC: no one uses AnalyzeBranchPredicate yet.

Add TargetInstrInfo::AnalyzeBranchPredicate and implement for x86.  A
later change adding support for page-fault based implicit null checks
depends on this.

Reviewers: reames, ab, atrick

Reviewed By: atrick

Subscribers: llvm-commits

Differential Revision: http://reviews.llvm.org/D10200

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@239742 91177308-0d34-0410-b5e6-96231b3b80d8
2015-06-15 18:44:21 +00:00
Sanjoy Das
319c91bbb0 [TargetInstrInfo] Rename getLdStBaseRegImmOfs and implement for x86.
Summary:

TargetInstrInfo::getLdStBaseRegImmOfs to
TargetInstrInfo::getMemOpBaseRegImmOfs and implement for x86.  The
implementation only handles a few easy cases now and will be made more
sophisticated in the future.

This is NFCI: the only user of `getLdStBaseRegImmOfs` (now
`getmemOpBaseRegImmOfs`) is `LoadClusterMotion` and `LoadClusterMotion`
is disabled for x86.

Reviewers: reames, ab, MatzeB, atrick

Reviewed By: MatzeB, atrick

Subscribers: llvm-commits

Differential Revision: http://reviews.llvm.org/D10199

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@239741 91177308-0d34-0410-b5e6-96231b3b80d8
2015-06-15 18:44:14 +00:00
Matthias Braun
6fee0b00e2 MachineLICM: Use TargetSchedModel instead of just itineraries
This will use Itinieraries if available, but will also work if just a
MCSchedModel is available.

Differential Revision: http://reviews.llvm.org/D10428

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@239658 91177308-0d34-0410-b5e6-96231b3b80d8
2015-06-13 03:42:11 +00:00
Ahmed Bougacha
fd83cb21ce [CodeGen] ArrayRef'ize cond/pred in various TII APIs. NFC.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@239553 91177308-0d34-0410-b5e6-96231b3b80d8
2015-06-11 19:30:37 +00:00
Sanjay Patel
c826b54b52 [x86] Add a reassociation optimization to increase ILP via the MachineCombiner pass
This is a reimplementation of D9780 at the machine instruction level rather than the DAG.

Use the MachineCombiner pass to reassociate scalar single-precision AVX additions (just a
starting point; see the TODO comments) to increase ILP when it's safe to do so.

The code is closely based on the existing MachineCombiner optimization that is implemented
for AArch64.

This patch should not cause the kind of spilling tragedy that led to the reversion of r236031.

Differential Revision: http://reviews.llvm.org/D10321



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@239486 91177308-0d34-0410-b5e6-96231b3b80d8
2015-06-10 20:32:21 +00:00
Keno Fischer
4332f869bf [InstrInfo] Refactor foldOperandImpl to thread through InsertPt. NFC
Summary:
This was a longstanding FIXME and is a necessary precursor to cases
where foldOperandImpl may have to create more than one instruction
(e.g. to constrain a register class). This is the split out NFC changes from
D6262.

Reviewers: pete, ributzka, uweigand, mcrosier

Reviewed By: mcrosier

Subscribers: mcrosier, ted, llvm-commits

Differential Revision: http://reviews.llvm.org/D10174

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@239336 91177308-0d34-0410-b5e6-96231b3b80d8
2015-06-08 20:09:58 +00:00
Benjamin Kramer
b22e2f9f2a ArrayRefize memory operand folding. NFC.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@230846 91177308-0d34-0410-b5e6-96231b3b80d8
2015-02-28 12:04:00 +00:00
Michael Kuperstein
acd5f13c88 [X86] Convert esp-relative movs of function arguments to pushes, step 2
This moves the transformation introduced in r223757 into a separate MI pass.
This allows it to cover many more cases (not only cases where there must be a 
reserved call frame), and perform rudimentary call folding. It still doesn't 
have a heuristic, so it is enabled only for optsize/minsize, with stack 
alignment <= 8, where it ought to be a fairly clear win.

(Re-commit of r227728)

Differential Revision: http://reviews.llvm.org/D6789


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@227752 91177308-0d34-0410-b5e6-96231b3b80d8
2015-02-01 16:56:04 +00:00
Michael Kuperstein
5b61b8f53c Revert r227728 due to bad line endings.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@227746 91177308-0d34-0410-b5e6-96231b3b80d8
2015-02-01 16:15:07 +00:00
Michael Kuperstein
59d9986259 [X86] Convert esp-relative movs of function arguments to pushes, step 2
This moves the transformation introduced in r223757 into a separate MI pass.
This allows it to cover many more cases (not only cases where there must be a 
reserved call frame), and perform rudimentary call folding. It still doesn't 
have a heuristic, so it is enabled only for optsize/minsize, with stack 
alignment <= 8, where it ought to be a fairly clear win.

Differential Revision: http://reviews.llvm.org/D6789

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@227728 91177308-0d34-0410-b5e6-96231b3b80d8
2015-02-01 11:44:44 +00:00
JF Bastien
7f0cbb5703 Revert "Insert random noops to increase security against ROP attacks (llvm)"
This reverts commit:
http://reviews.llvm.org/D3392

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@225948 91177308-0d34-0410-b5e6-96231b3b80d8
2015-01-14 05:24:33 +00:00
JF Bastien
21befa7761 Insert random noops to increase security against ROP attacks (llvm)
A pass that adds random noops to X86 binaries to introduce diversity with the goal of increasing security against most return-oriented programming attacks.

Command line options:
  -noop-insertion // Enable noop insertion.
  -noop-insertion-percentage=X // X% of assembly instructions will have a noop prepended (default: 50%, requires -noop-insertion)
  -max-noops-per-instruction=X // Randomly generate X noops per instruction. ie. roll the dice X times with probability set above (default: 1). This doesn't guarantee X noop instructions.

In addition, the following 'quick switch' in clang enables basic diversity using default settings (currently: noop insertion and schedule randomization; it is intended to be extended in the future).
  -fdiversify

This is the llvm part of the patch.
clang part: D3393

http://reviews.llvm.org/D3392
Patch by Stephen Crane (@rinon)

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@225908 91177308-0d34-0410-b5e6-96231b3b80d8
2015-01-14 01:07:26 +00:00
Robert Khasanov
d25d7bb372 [AVX512] Enable FP arithmetic lowering for AVX512VL subsets.
Added RegOp2MemOpTable4 to transform 4th operand from register to memory in merge-masked versions of instructions. 
Added lowering tests.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@224516 91177308-0d34-0410-b5e6-96231b3b80d8
2014-12-18 12:28:22 +00:00
Tom Roeder
63dea2c952 Add Forward Control-Flow Integrity.
This commit adds a new pass that can inject checks before indirect calls to
make sure that these calls target known locations. It supports three types of
checks and, at compile time, it can take the name of a custom function to call
when an indirect call check fails. The default failure function ignores the
error and continues.

This pass incidentally moves the function JumpInstrTables::transformType from
private to public and makes it static (with a new argument that specifies the
table type to use); this is so that the CFI code can transform function types
at call sites to determine which jump-instruction table to use for the check at
that site.

Also, this removes support for jumptables in ARM, pending further performance
analysis and discussion.

Review: http://reviews.llvm.org/D4167



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@221708 91177308-0d34-0410-b5e6-96231b3b80d8
2014-11-11 21:08:02 +00:00
Simon Pilgrim
0d1978b813 [X86] Memory folding for commutative instructions (updated)
This patch improves support for commutative instructions in the x86 memory folding implementation by attempting to fold a commuted version of the instruction if the original folding fails - if that folding fails as well the instruction is 're-commuted' back to its original order before returning.

Updated version of r219584 (reverted in r219595) - the commutation attempt now explicitly ensures that neither of the commuted source operands are tied to the destination operand / register, which was the source of all the regressions that occurred with the original patch attempt.

Added additional regression test case provided by Joerg Sonnenberger.

Differential Revision: http://reviews.llvm.org/D5818



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@220239 91177308-0d34-0410-b5e6-96231b3b80d8
2014-10-20 22:14:22 +00:00
NAKAMURA Takumi
58c0f65bf2 Revert r219584, "[X86] Memory folding for commutative instructions."
It broke i686 selfhosting.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@219595 91177308-0d34-0410-b5e6-96231b3b80d8
2014-10-13 04:17:34 +00:00
Simon Pilgrim
c00cd8e3c8 [X86] Memory folding for commutative instructions.
This patch improves support for commutative instructions in the x86 memory folding implementation by attempting to fold a commuted version of the instruction if the original folding fails - if that folding fails as well the instruction is 're-commuted' back to its original order before returning.

This mainly helps the stack inliner better fold reloads of 3 (or more) operand instructions (VEX encoded SSE etc.) but by performing this in the lowest foldMemoryOperandImpl implementation it also replaces the X86InstrInfo::optimizeLoadInstr version and is now used by FastISel too.

Differential Revision: http://reviews.llvm.org/D5701


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@219584 91177308-0d34-0410-b5e6-96231b3b80d8
2014-10-12 10:52:55 +00:00
Benjamin Kramer
00e08fcaa0 Canonicalize header guards into a common format.
Add header guards to files that were missing guards. Remove #endif comments
as they don't seem common in LLVM (we can easily add them back if we decide
they're useful)

Changes made by clang-tidy with minor tweaks.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@215558 91177308-0d34-0410-b5e6-96231b3b80d8
2014-08-13 16:26:38 +00:00
Juergen Ributzka
5f4e6e1ec0 [FastISel][X86] Optimize selects when the condition comes from a compare.
Optimize the select instructions sequence to use the EFLAGS directly from a
compare when possible.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@211543 91177308-0d34-0410-b5e6-96231b3b80d8
2014-06-23 21:55:36 +00:00
Juergen Ributzka
408691f967 [FastISel][X86] Refactor the code to get the X86 condition from a helper function. NFC.
Make use of helper functions to simplify the branch and compare instruction
selection in FastISel. Also add test cases for compare and conditonal branch.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@211077 91177308-0d34-0410-b5e6-96231b3b80d8
2014-06-16 23:58:24 +00:00
Eric Christopher
c6e5ff46be Remove the use of TargetMachine from X86InstrInfo.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@210596 91177308-0d34-0410-b5e6-96231b3b80d8
2014-06-10 22:34:31 +00:00
Tom Roeder
5d0f7af3dc Add a new attribute called 'jumptable' that creates jump-instruction tables for functions marked with this attribute.
It includes a pass that rewrites all indirect calls to jumptable functions to pass through these tables.

This also adds backend support for generating the jump-instruction tables on ARM and X86.
Note that since the jumptable attribute creates a second function pointer for a
function, any function marked with jumptable must also be marked with unnamed_addr.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@210280 91177308-0d34-0410-b5e6-96231b3b80d8
2014-06-05 19:29:43 +00:00
Alexey Volkov
0d0bab5168 [X86] Tune LEA usage for Silvermont
According to Intel Software Optimization Manual on Silvermont in some cases LEA
is better to be replaced with ADD instructions:
"The rule of thumb for ADDs and LEAs is that it is justified to use LEA
with a valid index and/or displacement for non-destructive destination purposes
(especially useful for stack offset cases), or to use a SCALE.
Otherwise, ADD(s) are preferable."

Differential Revision: http://reviews.llvm.org/D3826


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@209198 91177308-0d34-0410-b5e6-96231b3b80d8
2014-05-20 08:55:50 +00:00
Craig Topper
c34a25d59d [C++] Use 'nullptr'.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@207394 91177308-0d34-0410-b5e6-96231b3b80d8
2014-04-28 04:05:08 +00:00
Lang Hames
d285beabff [X86] As per suggestion from Craig Topper and Hal Finkel, override
TargetInstrInfo::findCommutedOpIndices to enable VFMA*231 commutation, rather
than abusing commuteInstruction.

Thanks very much for the suggestion guys!



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@205489 91177308-0d34-0410-b5e6-96231b3b80d8
2014-04-02 23:57:49 +00:00
Craig Topper
379e2cf307 [C++11] Mark more classes in the X86 target as 'final'.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@205166 91177308-0d34-0410-b5e6-96231b3b80d8
2014-03-31 06:53:13 +00:00
Craig Topper
59ae7294ef Prune includes in X86 target.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@204216 91177308-0d34-0410-b5e6-96231b3b80d8
2014-03-19 06:53:25 +00:00
Manuel Jacob
7e18b99f1e X86: Use enums for memory operand decoding instead of integer literals.
Summary:
X86BaseInfo.h defines an enum for the offset of each operand in a memory operand
sequence.  Some code uses it and some does not.  This patch replaces (hopefully)
all remaining locations where an integer literal was used instead of this enum.
No functionality change intended.

Reviewers: nadav

CC: llvm-commits, t.p.northover

Differential Revision: http://llvm-reviews.chandlerc.com/D3108

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@204158 91177308-0d34-0410-b5e6-96231b3b80d8
2014-03-18 16:14:11 +00:00
Craig Topper
feb0113a1e De-virtualize some methods since they don't override anything.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@203379 91177308-0d34-0410-b5e6-96231b3b80d8
2014-03-09 07:58:15 +00:00
Craig Topper
f2c9fef815 [C++11] Add 'override' keyword to virtual methods that override their base class.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@203378 91177308-0d34-0410-b5e6-96231b3b80d8
2014-03-09 07:44:38 +00:00
Craig Topper
629b96cb4f Switch all uses of LLVM_OVERRIDE to just use 'override' directly.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@202621 91177308-0d34-0410-b5e6-96231b3b80d8
2014-03-02 09:09:27 +00:00
Juergen Ributzka
354362524a [weak vtables] Remove a bunch of weak vtables
This patch removes most of the trivial cases of weak vtables by pinning them to
a single object file. The memory leaks in this version have been fixed. Thanks
Alexey for pointing them out.

Differential Revision: http://llvm-reviews.chandlerc.com/D2068

Reviewed by Andy

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@195064 91177308-0d34-0410-b5e6-96231b3b80d8
2013-11-19 00:57:56 +00:00
Alexey Samsonov
b21ab43cfc Revert r194865 and r194874.
This change is incorrect. If you delete virtual destructor of both a base class
and a subclass, then the following code:
  Base *foo = new Child();
  delete foo;
will not cause the destructor for members of Child class. As a result, I observe
plently of memory leaks. Notable examples I investigated are:
ObjectBuffer and ObjectBufferStream, AttributeImpl and StringSAttributeImpl.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@194997 91177308-0d34-0410-b5e6-96231b3b80d8
2013-11-18 09:31:53 +00:00
Juergen Ributzka
5a364c5561 [weak vtables] Remove a bunch of weak vtables
This patch removes most of the trivial cases of weak vtables by pinning them to
a single object file.

Differential Revision: http://llvm-reviews.chandlerc.com/D2068

Reviewed by Andy

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@194865 91177308-0d34-0410-b5e6-96231b3b80d8
2013-11-15 22:34:48 +00:00
Andrew Trick
a6a9ac5aa1 Fix the ExecutionDepsFix pass to handle AVX instructions.
This pass is needed to break false dependencies. Without it, unlucky
register assignment can result in wild (5x) swings in
performance. This pass was trying to handle AVX but not getting it
right. AVX doesn't have partial register defs, it has unused register
reads in which the high bits of a source operand are copied into the
unused bits of the dest.

Fixing this requires conservative liveness analysis. This is awkard
because the pass already has its own pseudo-liveness. However, proper
liveness is expensive, and we would like to use a generic utility to
compute it. The fix only invokes liveness on-demand. It is rare to
detect a case that needs undef-read dependence breaking, but when it
happens, it can be needed many times within a very large block.

I think the existing heuristic which uses a register window of 16 is
too conservative for loop-carried false dependencies. If the loop is a
reduction. The out-of-order engine may be able to execute several loop
iterations in parallel. However, I'll leave this tuning exercise for
next time.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@192635 91177308-0d34-0410-b5e6-96231b3b80d8
2013-10-14 22:19:03 +00:00
Andrew Trick
0f2eec65fb Add MI-Sched support for x86 macro fusion.
This is an awful implementation of the target hook. But we don't have
abstractions yet for common machine ops, and I don't see any quick way
to make it table-driven.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@184664 91177308-0d34-0410-b5e6-96231b3b80d8
2013-06-23 09:00:28 +00:00
David Blaikie
0187e7a9ba DebugInfo: remove target-specific Frame Index handling for DBG_VALUE MachineInstrs
Frame index handling is now target-agnostic, so delete the target hooks
for creation & asm printing of target-specific addressing in DBG_VALUEs
and any related functions.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@184067 91177308-0d34-0410-b5e6-96231b3b80d8
2013-06-16 20:34:27 +00:00
Tim Northover
e5609f3732 X86: Stop LEA64_32r doing unspeakable things to its arguments.
Previously LEA64_32r went through virtually the entire backend thinking it was
using 32-bit registers until its blissful illusions were cruelly snatched away
by MCInstLower and 64-bit equivalents were substituted at the last minute.

This patch makes it behave normally, and take 64-bit registers as sources all
the way through. Previous uses (for 32-bit arithmetic) are accommodated via
SUBREG_TO_REG instructions which make the types and classes agree properly.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@183693 91177308-0d34-0410-b5e6-96231b3b80d8
2013-06-10 20:43:49 +00:00
Michael Liao
b118a073d7 Re-work X86 code generation of atomic ops with spin-loop
- Rewrite/merge pseudo-atomic instruction emitters to address the
  following issue:
  * Reduce one unnecessary load in spin-loop

    previously the spin-loop looks like

        thisMBB:
        newMBB:
          ld  t1 = [bitinstr.addr]
          op  t2 = t1, [bitinstr.val]
          not t3 = t2  (if Invert)
          mov EAX = t1
          lcs dest = [bitinstr.addr], t3  [EAX is implicit]
          bz  newMBB
          fallthrough -->nextMBB

    the 'ld' at the beginning of newMBB should be lift out of the loop
    as lcs (or CMPXCHG on x86) will load the current memory value into
    EAX. This loop is refined as:

        thisMBB:
          EAX = LOAD [MI.addr]
        mainMBB:
          t1 = OP [MI.val], EAX
          LCMPXCHG [MI.addr], t1, [EAX is implicitly used & defined]
          JNE mainMBB
        sinkMBB:

  * Remove immopc as, so far, all pseudo-atomic instructions has
    all-register form only, there is no immedidate operand.

  * Remove unnecessary attributes/modifiers in pseudo-atomic instruction
    td

  * Fix issues in PR13458

- Add comprehensive tests on atomic ops on various data types.
  NOTE: Some of them are turned off due to missing functionality.

- Revise tests due to the new spin-loop generated.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@164281 91177308-0d34-0410-b5e6-96231b3b80d8
2012-09-20 03:06:15 +00:00
Manman Ren
127eea87d6 X86 Peephole: fold loads to the source register operand if possible.
Add more comments and use early returns to reduce nesting in isLoadFoldable.
Also disable folding for V_SET0 to avoid introducing a const pool entry and
a const pool load.

rdar://10554090 and rdar://11873276


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@161207 91177308-0d34-0410-b5e6-96231b3b80d8
2012-08-02 19:37:32 +00:00
Manman Ren
d7d003c2b7 X86 Peephole: fold loads to the source register operand if possible.
Machine CSE and other optimizations can remove instructions so folding
is possible at peephole while not possible at ISel.

This patch is a rework of r160919 and was tested on clang self-host on my local
machine.

rdar://10554090 and rdar://11873276


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@161152 91177308-0d34-0410-b5e6-96231b3b80d8
2012-08-02 00:56:42 +00:00
Manman Ren
e8b4a4a9d1 Revert r160920 and r160919 due to dragonegg and clang selfhost failure
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@160927 91177308-0d34-0410-b5e6-96231b3b80d8
2012-07-29 02:44:09 +00:00
Manman Ren
0eb3edea9c X86 Peephole: fold loads to the source register operand if possible.
Machine CSE and other optimizations can remove instructions so folding
is possible at peephole while not possible at ISel.

rdar://10554090 and rdar://11873276


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@160919 91177308-0d34-0410-b5e6-96231b3b80d8
2012-07-28 16:48:01 +00:00
Manman Ren
2af66dc51a X86: peephole optimization to remove cmp instruction
For each Cmp, we check whether there is an earlier Sub which make Cmp
redundant. We handle the case where SUB operates on the same source operands as
Cmp, including the case where the two source operands are swapped.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@159838 91177308-0d34-0410-b5e6-96231b3b80d8
2012-07-06 17:36:20 +00:00
Jakob Stoklund Olesen
59bde4d8a1 Add early if-conversion support to X86.
Implement the TII hooks needed by EarlyIfConversion to create cmov
instructions and estimate their latency.

Early if-conversion is still not enabled by default.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@159695 91177308-0d34-0410-b5e6-96231b3b80d8
2012-07-04 00:09:58 +00:00
Craig Topper
f318457547 Make helper method static since it doesn't use anything in the class.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@159071 91177308-0d34-0410-b5e6-96231b3b80d8
2012-06-23 04:58:41 +00:00