Commit Graph

3352 Commits

Author SHA1 Message Date
Chris Lattner 61797e3291 Fix 4366: store to null in non-default addr space should not be
turned into unreachable.

llvm-svn: 73195
2009-06-11 17:54:56 +00:00
Nick Lewycky 7ea68536b5 Don't crash on multiple return value with no obvious inserted value.
Fixes PR4314.

llvm-svn: 73007
2009-06-06 23:13:08 +00:00
Eli Friedman 73a83066d5 PR4340: Run SimplifyDemandedVectorElts on insertelement instructions;
sometimes it can find simplifications that won't be found otherwise.

llvm-svn: 73006
2009-06-06 20:08:03 +00:00
Jay Foad e57ba2eab5 Use cast<> instead of dyn_cast<> for things that are known to be
Instructions.

llvm-svn: 73002
2009-06-06 17:49:35 +00:00
Devang Patel 50fc5a3cd7 Simplify.
llvm-svn: 72965
2009-06-05 22:39:21 +00:00
Dan Gohman a5b9645c4b Split the Add, Sub, and Mul instruction opcodes into separate
integer and floating-point opcodes, introducing
FAdd, FSub, and FMul.

For now, the AsmParser, BitcodeReader, and IRBuilder all preserve
backwards compatability, and the Core LLVM APIs preserve backwards
compatibility for IR producers. Most front-ends won't need to change
immediately.

This implements the first step of the plan outlined here:
http://nondot.org/sabre/LLVMNotes/IntegerOverflow.txt

llvm-svn: 72897
2009-06-04 22:49:04 +00:00
Dan Gohman 7b6b5dd954 Don't do the X * 0.0 -> 0.0 transformation in instcombine, because
instcombine doesn't know when it's safe. To partially compensate
for this, introduce new code to do this transformation in
dagcombine, which can use UnsafeFPMath.

llvm-svn: 72872
2009-06-04 17:12:12 +00:00
Dan Gohman c380cca7ae Don't attempt to simplify an non-affine IV expression if it can't
be simplified to a loop-invariant value. This fixes PR4315.

llvm-svn: 72798
2009-06-03 19:11:31 +00:00
Dan Gohman 760377effc Fix CodeGenPrepare's address-mode sinking to handle unusual
addresses, involving Base values which do not have Pointer type.
This fixes PR4297.

llvm-svn: 72739
2009-06-02 21:29:13 +00:00
Eli Friedman ee94e3cc9e PR4286: Make RewriteLoadUserOfWholeAlloca and
RewriteStoreUserOfWholeAlloca deal with tail padding because 
isSafeUseOfBitCastedAllocation expects them to.  Otherwise, we crash 
trying to erase the bitcast.

llvm-svn: 72688
2009-06-01 09:14:32 +00:00
Owen Anderson cc0c75c74d Be more aggressive in doing LoadPRE by tracing backwards when a block only has
a single predecessor.

Patch by Jakub Staszak.

llvm-svn: 72661
2009-05-31 09:03:40 +00:00
Chris Lattner 221895303c fix PR4284, a bug in simplifylibcalls handling memcmp. Patch by
Benjamin Kramer!

llvm-svn: 72625
2009-05-30 18:43:04 +00:00
Bill Wendling 006459ecd4 Enable GVN Load PRE.
llvm-svn: 72589
2009-05-29 20:38:16 +00:00
Torok Edwin 0b0ddb21fe just show the instruction, its not that slow.
llvm-svn: 72577
2009-05-29 16:58:36 +00:00
Torok Edwin 6a94624a1b for instructions with void type we have no choice but print the instruction as
is, otherwise we get a <badref>.

llvm-svn: 72567
2009-05-29 10:28:44 +00:00
Torok Edwin 72070282eb Add a DEBUG() output to GVN that prints the instruction clobbering a load.
This is useful when trying to figure out why GVN didn't eliminate redundant
loads.

llvm-svn: 72565
2009-05-29 09:46:03 +00:00
Owen Anderson 04cfdd38a2 Fix an issue where phiMap was not being updated properly when doing load PRE.
Diagnosis and patch thanks to Jakub Staszak.

llvm-svn: 72562
2009-05-29 05:37:54 +00:00
Nick Lewycky 206876e2da Use Operands.data() instead of &Operands[0] where Operands is a potentially
empty SmallVector.

llvm-svn: 72512
2009-05-28 04:08:10 +00:00
Dan Gohman 4d1823680d Revert 72493 and replace it with a more conservative fix, for now: don't
rewrite the comparison if there is any implicit extension or truncation
on the induction variable. I'm planning for IVUsers to eventually take
over some of the work of this code, and for it to be generalized.

llvm-svn: 72496
2009-05-27 21:10:47 +00:00
Dan Gohman f4d85325c0 In ChangeCompareStride, when the stride to be reused is truncated to
a smaller type, promoted its offset back up to the type of the new
comparison. This fixes PR4222.

llvm-svn: 72493
2009-05-27 20:00:18 +00:00
Dan Gohman 8ca0885d69 Change ScalarEvolution::getSCEVAtScope to always return the original value
in the case where a loop exit value cannot be computed, instead of only in
some cases while using SCEVCouldNotCompute in others. This simplifies
getSCEVAtScope's callers.

llvm-svn: 72375
2009-05-24 23:25:42 +00:00
Torok Edwin 26895b518b Move Rewriter.clear() earlier, to avoid triggerring the AssertingVH by
one of the RecursivelyDeleteTriviallyDeadInstructions.
Add a comment explaining why the cache needs to be cleared.

llvm-svn: 72372
2009-05-24 20:08:21 +00:00
Torok Edwin 5349cf5f4b Instead of clearing the rewriter, don't attempt to rewrite dead phi nodes.
Also fix 80 column violation.

llvm-svn: 72371
2009-05-24 19:36:09 +00:00
Dan Gohman 4486da5b78 When rewriting the loop exit test with the canonical induction variable,
leave the original comparison in place if it has other uses, since the
other uses won't be dominated by the new comparison instruction.

llvm-svn: 72369
2009-05-24 19:11:38 +00:00
Dan Gohman fb56cf1b1d When replacing a floating-point comparison with an integer
comparison, use takeName to give the integer comparison a name.

llvm-svn: 72367
2009-05-24 18:09:01 +00:00
Torok Edwin d184bc209c The rewriter may hold references to instructions that are deleted because they are trivially dead.
Fix by clearing the rewriter cache before deleting the trivially dead
instructions.
Also make InsertedExpressions use an AssertingVH to catch these
bugs easier.

llvm-svn: 72364
2009-05-24 14:23:16 +00:00
Evan Cheng a838a40bc4 Fix bug in FoldFCmp_IntToFP_Cst. If inttofp is a uintofp, use unsigned instead of signed integer constant.
llvm-svn: 72300
2009-05-22 23:10:53 +00:00
Dan Gohman 781b75a7df Teach IndVarSimplify's FixUsesBeforeDefs to handle InvokeInsts by
assuming that the use of the value is in a block dominated by the
"normal" destination. LangRef.html and other documentation sources
don't explicitly guarantee this, but it seems to be assumed in
other places in LLVM at least.

This fixes an assertion failure on the included testcase, which
is derived from the Ada testsuite.

FixUsesBeforeDefs is a temporary measure which I'm looking to
replace with a more capable solution.

llvm-svn: 72266
2009-05-22 16:47:11 +00:00
Eli Friedman 0cf811df82 Fix loop-index-split to correctly preserve dominance frontiers. Part of
PR4238.

llvm-svn: 72244
2009-05-22 03:22:46 +00:00
Dan Gohman bf0002e7c1 Teach ValueTracking a new way to analyze PHI nodes, and and teach
Instcombine to be more aggressive about using SimplifyDemandedBits
on shift nodes. This allows a shift to be simplified to zero in the
included test case.

llvm-svn: 72204
2009-05-21 02:28:33 +00:00
Dan Gohman 7248923a5d Suppress the IV reversal transformation in the case that the RHS
of the comparison is defined inside the loop. This fixes a
use-before-def problem, because the transformation puts a use
of the RHS outside the loop.

llvm-svn: 72149
2009-05-20 00:34:08 +00:00
Dan Gohman 67587ce2e9 Remove an irrelevant comment.
llvm-svn: 72132
2009-05-19 20:38:47 +00:00
Dan Gohman 97f70add3c Add some more comments to the top of this file.
llvm-svn: 72131
2009-05-19 20:37:36 +00:00
Dan Gohman adc70d6806 Trim unneeded #includes.
llvm-svn: 72130
2009-05-19 20:35:26 +00:00
Dan Gohman 2649491f9c Teach SCEVExpander to expand arithmetic involving pointers into GEP
instructions. It attempts to create high-level multi-operand GEPs,
though in cases where this isn't possible it falls back to casting
the pointer to i8* and emitting a GEP with that. Using GEP instructions
instead of ptrtoint+arithmetic+inttoptr helps pointer analyses that
don't use ScalarEvolution, such as BasicAliasAnalysis.

Also, make the AddrModeMatcher more aggressive in handling GEPs.
Previously it assumed that operand 0 of a GEP would require a register
in almost all cases. It now does extra checking and can do more
matching if operand 0 of the GEP is foldable. This fixes a problem
that was exposed by SCEVExpander using GEPs.

llvm-svn: 72093
2009-05-19 02:15:55 +00:00
Dan Gohman 14d1339579 Rename UseTy to AccessTy, for consistency with getAccessType, and to
avoid ambiguity with the word "use" in IVStrideUse.

llvm-svn: 72012
2009-05-18 16:45:28 +00:00
Dale Johannesen f241df9abe Use abs64 in one more place.
llvm-svn: 71775
2009-05-14 16:47:34 +00:00
Chris Lattner 149546a6a0 calls in nothrow functions can be marked nothrow even if the callee
is not known to be nothrow.  This allows readnone/readonly functions
to be deleted even if we don't know whether the callee can throw.

llvm-svn: 71676
2009-05-13 17:39:14 +00:00
Chris Lattner 7e335a763a Fix PR4206 - crash in simplify lib calls
llvm-svn: 71644
2009-05-13 06:26:11 +00:00
Dale Johannesen 536de01bcf Add an int64_t variant of abs, for host environments
without one.  Use it where we were using abs on
int64_t objects.
(I strongly suspect the casts to unsigned in the
fragments in LoopStrengthReduce are not doing whatever
the original intent was, but the obvious change to
uint64_t doesn't work.  Maybe later.)

llvm-svn: 71612
2009-05-13 00:24:22 +00:00
Dan Gohman d76d71a291 Factor the code for collecting IV users out of LSR into an IVUsers class,
and generalize it so that it can be used by IndVarSimplify. Implement the
base IndVarSimplify transformation code using IVUsers. This removes
TestOrigIVForWrap and associated code, as ScalarEvolution now has enough
builtin overflow detection and folding logic to handle all the same cases,
and more. Run "opt -iv-users -analyze -disable-output" on your favorite
loop for an example of what IVUsers does.

This lets IndVarSimplify eliminate IV casts and compute trip counts in
more cases. Also, this happens to finally fix the remaining testcases
in PR1301.

Now that IndVarSimplify is being more aggressive, it occasionally runs
into the problem where ScalarEvolutionExpander's code for avoiding
duplicate expansions makes it difficult to ensure that all expanded
instructions dominate all the instructions that will use them. As a
temporary measure, IndVarSimplify now uses a FixUsesBeforeDefs function
to fix up instructions inserted by SCEVExpander. Fortunately, this code
is contained, and can be easily removed once a more comprehensive
solution is available.

llvm-svn: 71535
2009-05-12 02:17:14 +00:00
Evan Cheng 78a4eb844b Teach LSR to optimize more loop exit compares, i.e. change them to use postinc iv value. Previously LSR would only optimize those which are in the loop latch block. However, if LSR can prove it is safe (and profitable), it's now possible to change those not in the latch blocks to use postinc values.
Also, if the compare is the only use, LSR would place the iv increment instruction before the compare instead in the latch.

llvm-svn: 71485
2009-05-11 22:33:01 +00:00
Dale Johannesen 02cb2bf2e3 Reverse a loop that is counting up to a maximum to
count down to 0 instead, under very restricted
circumstances.  Adjust 4 testcases in which this
optimization fires.

llvm-svn: 71439
2009-05-11 17:15:42 +00:00
Duncan Sands af9eaa830a Rename PaddedSize to AllocSize, in the hope that this
will make it more obvious what it represents, and stop
it being confused with the StoreSize.

llvm-svn: 71349
2009-05-09 07:06:46 +00:00
Evan Cheng b9dcc2c0c9 Factor out code that optimize loop terminating condition.
llvm-svn: 71305
2009-05-09 01:08:24 +00:00
Chris Lattner c48091f141 fix RewriteStoreUserOfWholeAlloca to use the correct type size
method, fixing a crash on PR4146.  While the store will 
ultimately overwrite the "padded size" number of bits in memory,
the stored value may be a subset of this size.  This function
only wants to handle the case where all bits are stored.

llvm-svn: 71224
2009-05-08 15:54:41 +00:00
Nick Lewycky 702fbf94a0 This transform requires valid TargetData info. Wrap it in 'if (TD)' in
preparation for the day we use null TargetData when no target is specified.

llvm-svn: 71210
2009-05-08 06:47:37 +00:00
Dan Gohman 140a6f24f0 Perform constant folding on operands of instructions with non-void
types, such as loads and calls.

llvm-svn: 71175
2009-05-07 19:43:39 +00:00
Evan Cheng 342053cd27 Unbreak the build.
llvm-svn: 71091
2009-05-06 18:00:56 +00:00
David Greene 0dec5b9a75 Make sure to use signed arithmetic in APInt to fix a regression.
llvm-svn: 71090
2009-05-06 17:39:26 +00:00
Duncan Sands 1efabaaa2a Allow readonly functions to unwind exceptions. Teach
the optimizers about this.  For example, a readonly
function with no uses cannot be removed unless it is
also marked nounwind.

llvm-svn: 71071
2009-05-06 06:49:50 +00:00
Dan Gohman e58fc20f8d Fix a copy+pasto in a comment.
llvm-svn: 71035
2009-05-05 23:02:38 +00:00
Dan Gohman 96b18ccdd3 Delete a FIXME which is no longer relevant, and add a FIXME that is.
llvm-svn: 71033
2009-05-05 22:59:55 +00:00
Bill Wendling 5e2ac0cd9c Temporarily reverting r71008. It was causing this failure:
Running /Volumes/Sandbox/Buildbot/llvm/full-llvm/build/llvm.src/test/
CodeGen/X86/dg.exp ...
FAIL: /Volumes/Sandbox/Buildbot/llvm/full-llvm/build/llvm.src/test/
CodeGen/X86/change-compare-stride-1.ll
Failed with exit(1) at line 2
while running: grep {cmpq       $-478,} change-compare-stride-1.ll.tmp
child process exited abnormally

llvm-svn: 71013
2009-05-05 20:49:46 +00:00
David Greene 246a3dfb10 Handle overflow of 64-bit loop conditions.
llvm-svn: 71008
2009-05-05 20:22:36 +00:00
Dan Gohman 48f8222293 Re-apply 70645, converting ScalarEvolution to use
CallbackVH, with fixes. allUsesReplacedWith need to
walk the def-use chains and invalidate all users of a
value that is replaced. SCEVs of users need to be
recalcualted even if the new value is equivalent. Also,
make forgetLoopPHIs walk def-use chains, since any
SCEV that depends on a PHI should be recalculated when
more information about that PHI becomes available.

llvm-svn: 70927
2009-05-04 22:30:44 +00:00
Dan Gohman a30370bc33 Constify a bunch of SCEV-using code.
llvm-svn: 70919
2009-05-04 22:02:23 +00:00
Chris Lattner fa552d728d fix some problems spotted by Duncan and Nicolas Geoffray
llvm-svn: 70872
2009-05-04 16:29:24 +00:00
Chris Lattner d579cb1167 * Sink 4 duplicates of edge threading validity checks and DOUT prints into
ThreadEdge directly.  This shares the code, but is just a refactoring.
* Make JumpThreading compute the set of loop headers and avoid threading
  across them.  This prevents jump threading from forming irreducible 
  loops (goodness) but also prevents it from threading in other cases that
  are beneficial (see the comment above FindFunctionBackedges).

llvm-svn: 70820
2009-05-04 02:28:08 +00:00
Chris Lattner 351134ba93 Factor loop backedge finding out of CodeGenPrepare into a new
FindFunctionBackedges function.

llvm-svn: 70819
2009-05-04 02:25:58 +00:00
Dan Gohman 5036695c32 Revert r70645 for now; it's causing a variety of regressions.
llvm-svn: 70661
2009-05-03 05:46:20 +00:00
Dan Gohman e9a38d16fe Convert ScalarEvolution to use CallbackVH for its internal map. This
makes ScalarEvolution::deleteValueFromRecords, and it's code that
subtly needed to be called before ReplaceAllUsesWith, unnecessary.

It also makes ValueDeletionListener unnecessary.

llvm-svn: 70645
2009-05-02 21:19:20 +00:00
Dan Gohman ff08995589 Previously, RecursivelyDeleteDeadInstructions provided an option
of returning a list of pointers to Values that are deleted. This was
unsafe, because the pointers in the list are, by nature of what
RecursivelyDeleteDeadInstructions does, always dangling. Replace this
with a simple callback mechanism. This may eventually be removed if
all clients can reasonably be expected to use CallbackVH.

Use this to factor out the dead-phi-cycle-elimination code from LSR
utility function, and generalize it to use the
RecursivelyDeleteTriviallyDeadInstructions utility function.

This makes LSR more aggressive about eliminating dead PHI cycles;
adjust tests to either be less trivial or to simply expect fewer
instructions.

llvm-svn: 70636
2009-05-02 18:29:22 +00:00
Dan Gohman c27345f0b4 Tell ScalarEvolution that the loop is being deleted before actually
deleting it.  This will let ScalarEvolution be more complete about
updating its records.

llvm-svn: 70632
2009-05-02 17:29:26 +00:00
Dan Gohman 6409e7d4e9 Don't split critical edges during the AddUsersIfInteresting phase
of LSR. This makes the AddUsersIfInteresting phase of LSR a pure
analysis instead of a phase that potentially does CFG modifications.

The conditions where this code would actually perform a split are
rare, and in the cases where it actually would do a split the split
is usually undone by CodeGenPrepare, and in cases where splits
actually survive into codegen, they appear to hurt more often than
they help.

llvm-svn: 70625
2009-05-02 05:36:01 +00:00
Dan Gohman 65dbe7874f Make RequiresTypeConversion canonicalize the types before calling the
target hooks canLosslesslyBitCastTo and isTruncateFree. This allows
targets to avoid worrying about handling all combinations of integer
and pointer types.

llvm-svn: 70555
2009-05-01 17:07:43 +00:00
Dan Gohman d3aa4215ef Minor whitespace fix.
llvm-svn: 70551
2009-05-01 16:56:32 +00:00
Dan Gohman 6be8530158 Fix some code to work if TargetLowering is not available.
llvm-svn: 70546
2009-05-01 16:29:14 +00:00
Dale Johannesen f4031bd01e Print correct instruction in dump.
llvm-svn: 70427
2009-04-29 22:57:20 +00:00
Dan Gohman 8ddd0b3599 Reword and tidy up some comments.
llvm-svn: 70416
2009-04-29 22:01:05 +00:00
Dan Gohman 3e6e188ee3 Remove an obsolete comment.
llvm-svn: 70262
2009-04-27 22:12:34 +00:00
Dale Johannesen 27b4f222cf Fix PR 4086, a bug in FP IV elimination.
llvm-svn: 70247
2009-04-27 21:03:15 +00:00
Dan Gohman e99f98262c Permit ChangeCompareStride to rewrite a comparison when the factor
between the comparison's iv stride and the candidate stride is
exactly -1.

llvm-svn: 70244
2009-04-27 20:35:32 +00:00
Dan Gohman 1b5055ab7f Return null instead of false, as appropriate.
llvm-svn: 70054
2009-04-25 17:28:45 +00:00
Dan Gohman 5638e0d642 Add several more icmp simplifications. Transform signed comparisons
into unsigned ones when the operands are known to have the same
sign bit value.

llvm-svn: 70053
2009-04-25 17:12:48 +00:00
Sanjiv Gupta 46c97e626f Allow i16 type indices to gep.
llvm-svn: 69946
2009-04-24 02:37:54 +00:00
Dan Gohman 86bcd97014 Change SCEVExpander's expandCodeFor to provide more flexibility
with the persistent insertion point, and change IndVars to make
use of it. This fixes a bug where IndVars was holding on to a
stale insertion point and forcing the SCEVExpander to continue to
use it.

This fixes PR4038.

llvm-svn: 69892
2009-04-23 15:16:49 +00:00
Evan Cheng d8174d3d09 Make sure both operands have binary instructions have the same type.
llvm-svn: 69844
2009-04-22 23:39:28 +00:00
Evan Cheng 59ca33053b A few more places where the check of use_empty is needed.
llvm-svn: 69842
2009-04-22 23:09:16 +00:00
Evan Cheng cbfe9df096 Avoid deferencing use_begin() if value does not have a use.
llvm-svn: 69836
2009-04-22 22:45:37 +00:00
Chris Lattner 69223bb7f5 fix a crash on a pointless but valid zero-length memset, rdar://6808691
llvm-svn: 69680
2009-04-21 16:52:12 +00:00
Dan Gohman 4860db61be Factor out a common base class from SCEVTruncateExpr, SCEVZeroExtendExpr,
and SCEVSignExtendExpr.

llvm-svn: 69649
2009-04-21 01:25:57 +00:00
Dan Gohman b397e1a7a2 Introduce encapsulation for ScalarEvolution's TargetData object, and refactor
the code to minimize dependencies on TargetData.

llvm-svn: 69644
2009-04-21 01:07:12 +00:00
Dale Johannesen 1238220473 Adjust loop size estimate for full unrolling;
GEP's don't usually become instructions.

llvm-svn: 69631
2009-04-20 22:19:33 +00:00
Sanjiv Gupta 428d490332 Before trying to introduce/eliminate cast/ext/trunc to make indices type as
pointer type, make sure that the pointer size is a valid sequential index type.

llvm-svn: 69574
2009-04-20 06:05:54 +00:00
Dan Gohman 056857aa21 Use more const qualifiers with SCEV interfaces.
llvm-svn: 69450
2009-04-18 17:56:28 +00:00
Dan Gohman d2d6fd806c Don't create ConstantInts with pointer type. This fixes a
regression in 403.gcc in PIC_CODEGEN=1 and DISABLE_LTO=1
mode.

llvm-svn: 69344
2009-04-17 02:02:52 +00:00
Dan Gohman fec1d086e0 Use TargetData::getTypeSizeInBits instead of getPrimitiveSizeInBits()
to get the correct answer for pointer types.

llvm-svn: 69321
2009-04-16 22:35:57 +00:00
Dan Gohman 8b6ebb1112 Minor code simplifications. Don't attempt LSR on theoretical
targets with pointers larger than 64 bits, due to the code not
yet being APInt clean.

llvm-svn: 69296
2009-04-16 16:49:48 +00:00
Dan Gohman e2ead2c328 LSR is no longer a GEP optimizer. It is now an IV expression
optimizer, which just happen to frequently involve optimizing GEPs.

llvm-svn: 69295
2009-04-16 16:46:01 +00:00
Dan Gohman a8be04b2db Use ConstantExpr::getIntToPtr instead of SCEVExpander::InsertCastOfTo,
since the operand is always a constant.

llvm-svn: 69291
2009-04-16 15:48:38 +00:00
Dan Gohman 71bccd3e0e Use a SCEV expression cast instead of immediately inserting a
new instruction with SCEVExpander::InsertCastOfTo.

llvm-svn: 69290
2009-04-16 15:47:35 +00:00
Dan Gohman 0a40ad93a9 Expand GEPs in ScalarEvolution expressions. SCEV expressions can now
have pointer types, though in contrast to C pointer types, SCEV
addition is never implicitly scaled. This not only eliminates the
need for special code like IndVars' EliminatePointerRecurrence
and LSR's own GEP expansion code, it also does a better job because
it lets the normal optimizations handle pointer expressions just
like integer expressions.

Also, since LLVM IR GEPs can't directly index into multi-dimensional
VLAs, moving the GEP analysis out of client code and into the SCEV
framework makes it easier for clients to handle multi-dimensional
VLAs the same way as other arrays.

Some existing regression tests show improved optimization.
test/CodeGen/ARM/2007-03-13-InstrSched.ll in particular improved to
the point where if-conversion started kicking in; I turned it off
for this test to preserve the intent of the test.

llvm-svn: 69258
2009-04-16 03:18:22 +00:00
Dale Johannesen a71daa83c6 Eliminate zext over (iv | const) or (signed iv),
and sext over (iv | const), if a longer iv is
available.  Allow expressions to have more than
one zext/sext parent.  All from OpenSSL.

llvm-svn: 69241
2009-04-15 23:31:51 +00:00
Dale Johannesen 82230b5b17 Eliminate zext over (iv & const) or ((iv+const)&const)
if a longer iv is available.  These subscript forms are
not common; they're a bottleneck in OpenSSL.

llvm-svn: 69215
2009-04-15 20:41:02 +00:00
Dale Johannesen 7ffb7d5728 Enhance induction variable code to remove the
sext around sext(shorter IV + constant), using a
longer IV instead, when it can figure out the
add can't overflow.  This comes up a lot in
subscripting; mainly affects 64 bit.

llvm-svn: 69123
2009-04-15 01:10:12 +00:00
Evan Cheng ffb83a155e Avoid making the transformation enabled by my last patch if the new destinations have phi nodes.
llvm-svn: 69121
2009-04-15 00:43:54 +00:00
Evan Cheng 5ebf2acd84 Optimize conditional branch on i1 phis with non-constant inputs.
This turns:

eq:
        %3 = icmp eq i32 %1, %2
        br label %join

ne:
        %4 = icmp ne i32 %1, %2
        br label %join

join:
        %5 = phi i1 [%3, %eq], [%4, %ne]
        br i1 %5, label %yes, label %no

=>

eq:
        %3 = icmp eq i32 %1, %2
        br i1 %3, label %yes, label %no

ne:
        %4 = icmp ne i32 %1, %2
        br i1 %4, label %yes, label %no

llvm-svn: 69102
2009-04-14 23:40:03 +00:00
Owen Anderson a1902318e3 LoopIndexSplit needs to inform the loop pass manager of the instructions it is
deleting, not just the basic block.

llvm-svn: 69011
2009-04-14 01:04:19 +00:00
Chris Lattner 6cd82fb430 "There was a typo in my previous patch which leads to miscompilation of
strncat :(

strncat(foo, "bar", 99)
would be optimized to
memcpy(foo+strlen(foo), "bar", 100, 1)
instead of
memcpy(foo+strlen(foo), "bar", 4, 1)"

Patch by Benjamin Kramer!

llvm-svn: 68905
2009-04-12 18:22:33 +00:00