directory. These passes are already defined in the IR library, and it
doesn't make any sense to have the headers in Analysis.

Long term, I think there is going to be a much better way to divide
these matters. The dominators code should be fully separated into the
abstract graph algorithm and have that put in Support where it becomes
obvious that evn Clang's CFGBlock's can use it. Then the verifier can
manually construct dominance information from the Support-driven
interface while the Analysis library can provide a pass which both
caches, reconstructs, and supports a nice update API.

But those are very long term, and so I don't want to leave the really
confusing structure until that day arrives.

llvm-svn: 199082

case when the lookup table doesn't have any holes.

This means we can build a lookup table for switches like this:

  switch (x) {
    case 0: return 1;
    case 1: return 2;
    case 2: return 3;
    case 3: return 4;
    default: exit(1);
  }

The default case doesn't yield a constant result here, but that doesn't matter,
since a default result is only necessary for filling holes in the lookup table,
and this table doesn't have any holes.

This makes us transform 505 more switches in a clang bootstrap, and shaves 164 KB
off the resulting clang binary.

llvm-svn: 199025

subsequent changes are easier to review. About to fix some layering
issues, and wanted to separate out the necessary churn.

Also comment and sink the include of "Windows.h" in three .inc files to
match the usage in Memory.inc.

llvm-svn: 198685

Now with a fix for PR18384: ValueHandleBase::ValueIsDeleted.

We need to invalidate SCEV's loop info when we delete a block, even if no values are hoisted.

llvm-svn: 198631

This commit was the source of crasher PR18384:

While deleting: label %for.cond127
An asserting value handle still pointed to this value!
UNREACHABLE executed at llvm/lib/IR/Value.cpp:671!

Reverting to get the builders green, feel free to re-land after fixing up.
(Renato has a handy isolated repro if you need it.)

This reverts commit r198478.

llvm-svn: 198503

getSCEV for an ashr instruction creates an intermediate zext
expression when it truncates its operand.

The operand is initially inside the loop, so the narrow zext
expression has a non-loop-invariant loop disposition.

LoopSimplify then runs on an outer loop, hoists the ashr operand, and
properly invalidate the SCEVs that are mapped to value.

The SCEV expression for the ashr is now an AddRec with the hoisted
value as the now loop-invariant start value.

The LoopDisposition of this wide value was properly invalidated during
LoopSimplify.

However, if we later get the ashr SCEV again, we again try to create
the intermediate zext expression. We get the same SCEV that we did
earlier, and it is still cached because it was never mapped to a
Value. When we try to create a new AddRec we abort because we're using
the old non-loop-invariant LoopDisposition.

I don't have a solution for this other than to clear LoopDisposition
when LoopSimplify hoists things.

I think the long-term strategy should be to perform LoopSimplify on
all loops before computing SCEV and before running any loop opts on
individual loops. It's possible we may want to rerun LoopSimplify on
individual loops, but it should rarely do anything, so rarely require
invalidating SCEV.

llvm-svn: 198478

Split sadd.with.overflow into add + sadd.with.overflow to allow
analysis and optimization. This should ideally be done after
InstCombine, which can perform code motion (eventually indvars should
run after all canonical instcombines). We want ISEL to recombine the
add and the check, at least on x86.

This is currently under an option for reducing live induction
variables: -liv-reduce. The next step is reducing liveness of IVs that
are live out of the overflow check paths. Once the related
optimizations are fully developed, reviewed and tested, I do expect
this to become default.

llvm-svn: 197926

Summary:
Before this change the instrumented code before Ret instructions looked like:
  <Unpoison Frame Redzones>
  if (Frame != OriginalFrame) // I.e. Frame is fake
     <Poison Complete Frame>

Now the instrumented code looks like:
  if (Frame != OriginalFrame) // I.e. Frame is fake
     <Poison Complete Frame>
  else
     <Unpoison Frame Redzones>

Reviewers: eugenis

Reviewed By: eugenis

CC: llvm-commits

Differential Revision: http://llvm-reviews.chandlerc.com/D2458

llvm-svn: 197907

If we happen to eliminate every case in a switch that has branch
weights, we currently try to create metadata for the one remaining
branch, triggering an assert. Instead, we need to check that the
metadata we're trying to create is sensible.

llvm-svn: 197791

Currently SplitBlockAndInsertIfThen requires that branch condition is an
Instruction itself, which is very inconvenient, because it is sometimes an
Operator, or even a Constant.

llvm-svn: 197677

Enable double to float shrinking optimizations for binary functions like 'fmin/fmax'. Fix radar:15283121

llvm-svn: 197434

llvm-svn: 197109

This avoids creating branch weight metadata of length one when we fold
cases into the default of a switch instruction, which was triggering
an assert.

llvm-svn: 196845

llvm-svn: 196732

This fixes PR17872.  This bug can lead to C++ destructors not being
called when they should be, when an exception is thrown.

llvm-svn: 196711

Before this change, inlining one "invoke" into an outer "invoke" call
site can lead to the outer landingpad's catch/filter clauses being
copied multiple times into the resulting landingpad.  This happens:

 * when the inlined function contains multiple "resume" instructions,
   because forwardResume() copies the clauses but is called multiple
   times;

 * when the inlined function contains a "resume" and a "call", because
   HandleCallsInBlockInlinedThroughInvoke() copies the clauses but is
   redundant with forwardResume().

Fix this by deduplicating the code.

This problem doesn't lead to any incorrect execution; it's only
untidy.

This change will make fixing PR17872 a little easier.

llvm-svn: 196710

overall time of LLVM compilation by ~1%.

llvm-svn: 196667

llvm-svn: 196574

Summary:
Rewrite asan's stack frame layout.
First, most of the stack layout logic is moved into a separte file
to make it more testable and (potentially) useful for other projects.
Second, make the frames more compact by using adaptive redzones
(smaller for small objects, larger for large objects).
Third, try to minimized gaps due to large alignments (this is hypothetical since
today we don't see many stack vars aligned by more than 32).

The frames indeed become more compact, but I'll still need to run more benchmarks
before committing, but I am sking for review now to get early feedback.

This change will be accompanied by a trivial change in compiler-rt tests
to match the new frame sizes.

Reviewers: samsonov, dvyukov

Reviewed By: samsonov

CC: llvm-commits

Differential Revision: http://llvm-reviews.chandlerc.com/D2324

llvm-svn: 196568

llvm-svn: 196544

This patch tries to avoid unrelated changes other than fixing a few
hyphen-related ambiguities and contractions in nearby lines.

llvm-svn: 196471

Remove some associated dead code.

This cleanup is associated with PR17872.

llvm-svn: 196147

Patch by Dmitri Shtilman!

llvm-svn: 195116

lowering only for load/stores to scalar allocas. The resulting values
confuse the backend and don't add anything because we can describe
array-allocas with a dbg.declare intrinsic just fine.

rdar://problem/15464571

llvm-svn: 195052

eraseFromParent() invalidates OldName.

llvm-svn: 194970

Generally speaking, control flow paths with error reporting calls are cold.
So far, error reporting calls are calls to perror and calls to fprintf,
fwrite, etc. with stderr as the stream. This can be extended in the future.

The primary motivation is to improve block placement (the cold attribute
affects the static branch prediction heuristics).

llvm-svn: 194943

llvm-svn: 194601

FoldBranchToCommonDest merges branches into a single branch with or/and of the condition. It has a heuristics for estimating when some of the dependencies are processed by out-of-order processors. This patch adds another rule to the heuristics that says that if the "BonusInstruction" that we speculatively execute is used by the condition of the second branch then it is okay to hoist it. This change exposes more opportunities for other passes to transform the code. It does not matter that much that we if-convert the code because the selectiondag builder splits or/and branches into multiple branches when profitable.

llvm-svn: 194524

Both simpler and more powerful than the hand-rolled folding logic.

llvm-svn: 194475

This should be inconsequential and is work
towards removing the default address space
arguments.

llvm-svn: 194347

SimplifyCFG has a heuristics for out-of-order processors that decides when it is worthwhile to merge branches. It tries to estimate if the operands of the instruction that we want to hoist are ready. This commit marks function arguments as 'ready' because they require no calculation. This boosts libquantum and a few other workloads from the testsuite.
  

llvm-svn: 194346

This reverts commit r193356, it caused PR17781.

A reduced test case covering this regression has been added to the test suite.

llvm-svn: 193955

This adds an SimplifyLibCalls case which converts the special __sinpi and
__cospi (float & double variants) into a __sincospi_stret where appropriate to
remove duplicated work.

Patch by Tim Northover

llvm-svn: 193943

Given that backend does not handle "invoke asm" correctly ("invoke asm" will be
handled by SelectionDAGBuilder::visitInlineAsm, which does not have the right
setup for LPadToCallSiteMap) and we already made the assumption that inline asm
does not throw in InstCombiner::visitCallSite, we are going to make the same
assumption in Inliner to make sure we don't convert "call asm" to "invoke asm".

If it becomes necessary to add support for "invoke asm" later on, we will need
to modify the backend as well as remove the assumptions that inline asm does
not throw.

Fix rdar://15317907

llvm-svn: 193808

This patch implements quick look-up for block in loop by maintaining a hash set for blocks.
It improves the efficiency of loop analysis a lot, the biggest improvement could be 5-6%(458.sjeng).
Below are the compilation time for our benchmark in llc before & after the patch.

Benchmark	llc - trunk		llc - patched	
401.bzip2	0.339081	100.00%	0.329657	102.86%
403.gcc		19.853966	100.00%	19.605466	101.27%
429.mcf		0.049823	100.00%	0.048451	102.83%
433.milc	0.514898	100.00%	0.510217	100.92%
444.namd	1.109328	100.00%	1.103481	100.53%
445.gobmk	4.988028	100.00%	4.929114	101.20%
456.hmmer	0.843871	100.00%	0.825865	102.18%
458.sjeng	0.754238	100.00%	0.714095	105.62%
464.h264ref	2.9668		100.00%	2.90612		102.09%
471.omnetpp	4.556533	100.00%	4.511886	100.99%
bitmnp01	0.038168	100.00%	0.0357		106.91%
idctrn01	0.037745	100.00%	0.037332	101.11%
libquake2	3.78689		100.00%	3.76209		100.66%
libquake_	2.251525	100.00%	2.234104	100.78%
linpack		0.033159	100.00%	0.032788	101.13%
matrix01	0.045319	100.00%	0.043497	104.19%
nbench		0.333161	100.00%	0.329799	101.02%
tblook01	0.017863	100.00%	0.017666	101.12%
ttsprk01	0.054337	100.00%	0.053057	102.41%

Reviewer	: Andrew Trick <atrick@apple.com>, Hal Finkel <hfinkel@anl.gov>
Approver	: Andrew Trick <atrick@apple.com>
Test		: Pass make check-all & llvm test-suite

llvm-svn: 193460

This patch teaches GlobalStatus to analyze a call that uses the global value as
a callee, not as an argument.

With this change internalize call handle the common use of linkonce_odr
functions. This reduces the number of linkonce_odr functions in a LTO build of
clang (checked with the emit-llvm gold plugin option) from 1730 to 60.

llvm-svn: 193436

Patch by: Vincent Lejeune

llvm-svn: 193356

v2:
  - Use CI->cannotDuplicate()

llvm-svn: 193115

llvm-svn: 193104

When a linkonce_odr value that is on the dso list is not unnamed_addr
we can still look to see if anything is actually using its address. If
not, it is safe to hide it.

This patch implements that by moving GlobalStatus to Transforms/Utils
and using it in Internalize.

llvm-svn: 193090