Commit Graph

238 Commits

Author SHA1 Message Date
Dario Domizioli
da704bf346 Revert test commit. Removed blank line.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@208308 91177308-0d34-0410-b5e6-96231b3b80d8
2014-05-08 12:54:43 +00:00
Dario Domizioli
a054f10ffe Test commit. Added blank line.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@208298 91177308-0d34-0410-b5e6-96231b3b80d8
2014-05-08 11:28:14 +00:00
Chandler Carruth
d6d57bc3fb [inliner] Significantly improve the compile time in cases like PR19499
by avoiding inlining massive switches merely because they have no
instructions in them. These switches still show up where we fail to form
lookup tables, and in those cases they are actually going to cause
a very significant code size hit anyways, so inlining them is not the
right call. The right way to fix any performance regressions stemming
from this is to enhance the switch-to-lookup-table logic to fire in more
places.

This makes PR19499 about 5x less bad. It uncovers a second compile time
problem in that test case that is unrelated (surprisingly!).

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@207403 91177308-0d34-0410-b5e6-96231b3b80d8
2014-04-28 08:52:44 +00:00
Manman Ren
3bd471dee2 [inline cold threshold] Command line argument for inline threshold will
override the default cold threshold.

When we use command line argument to set the inline threshold, the default
cold threshold will not be used. This is in line with how we use
OptSizeThreshold. When we want a higher threshold for all functions, we
do not have to set both inline threshold and cold threshold.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@207245 91177308-0d34-0410-b5e6-96231b3b80d8
2014-04-25 17:34:55 +00:00
Reid Kleckner
0df9abbd63 Fix PR7272 in -tailcallelim instead of the inliner
The -tailcallelim pass should be checking if byval or inalloca args can
be captured before marking calls as tail calls.  This was the real root
cause of PR7272.

With a better fix in place, revert the inliner change from r105255.  The
test case it introduced still passes and has been moved to
test/Transforms/Inline/byval-tail-call.ll.

Reviewers: chandlerc

Differential Revision: http://reviews.llvm.org/D3403

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@206789 91177308-0d34-0410-b5e6-96231b3b80d8
2014-04-21 20:48:47 +00:00
Gerolf Hoflehner
d5e9413512 Reverse 206485.
After some discussions the preferred semantics of
the always_inline attribute is
inline always when the compiler can determine
that it it safe to do so.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@206487 91177308-0d34-0410-b5e6-96231b3b80d8
2014-04-17 19:14:06 +00:00
Gerolf Hoflehner
d6312bbbbd Inline a function when the always_inline attribute
is set even when it contains a indirect branch.
The attribute overrules correctness concerns
like the escape of a local block address.

This is for rdar://16501761




git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@206429 91177308-0d34-0410-b5e6-96231b3b80d8
2014-04-17 00:21:52 +00:00
Julien Lerouge
894b7f642c Add lifetime markers for allocas created to hold byval arguments, make them
appear in the InlineFunctionInfo.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@206308 91177308-0d34-0410-b5e6-96231b3b80d8
2014-04-15 18:06:46 +00:00
Eric Christopher
9a764dfa92 Handle vlas during inline cost computation if they'll be turned
into a constant size alloca by inlining.

Ran a run over the testsuite, no results out of the noise, fixes
the testcase in the PR.

PR19115.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@205710 91177308-0d34-0410-b5e6-96231b3b80d8
2014-04-07 13:36:21 +00:00
Manman Ren
c7ac256d52 Set default of inlinecold-threshold to 225.
225 is the default value of inline-threshold. This change will make sure
we have the same inlining behavior as prior to r200886.

As Chandler points out, even though we don't have code in our testing
suite that uses cold attribute, there are larger applications that do
use cold attribute.

r200886 + this commit intend to keep the same behavior as prior to r200886.
We can later on tune the inlinecold-threshold.

The main purpose of r200886 is to help performance of instrumentation based
PGO before we actually hook up inliner with analysis passes such as BPI and BFI.
For instrumentation based PGO, we try to increase inlining of hot functions and
reduce inlining of cold functions by setting inlinecold-threshold.

Another option suggested by Chandler is to use a boolean flag that controls
if we should use OptSizeThreshold for cold functions. The default value
of the boolean flag should not change the current behavior. But it gives us
less freedom in controlling inlining of cold functions.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@200898 91177308-0d34-0410-b5e6-96231b3b80d8
2014-02-06 01:59:22 +00:00
Manman Ren
df7da79db6 Inliner uses a smaller inline threshold for callees with cold attribute.
Added command line option inlinecold-threshold to set threshold for inlining
functions with cold attribute. Listen to the cold attribute when it would
decrease the inline threshold.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@200886 91177308-0d34-0410-b5e6-96231b3b80d8
2014-02-05 22:53:44 +00:00
Chandler Carruth
d383b8eec3 [inliner] Skip debug intrinsics even earlier in computing the inline
cost so that they don't impact the vector bonus. Fundamentally, counting
unsimplified instructions is just *wrong*; it will continue to introduce
instability as things which do not generate code bizarrely impact
inlining. For example, sufficiently nested inlined functions could turn
off the vector bonus with lifetime markers just like the debug
intrinsics do. =/

This is a short-term tactical fix. Long term, I think we need to remove
the vector bonus entirely. That's a separate patch and discussion
though.

The patch to fix this provided by Dario Domizioli. I've added some
comments about the planned direction and used a heavily pruned form of
debug info intrinsics for the test case. While this debug info doesn't
work or "do" anything useful, it lets us easily test all manner of
interference easily, and I suspect this will not be the last time we
want to craft a pattern where debug info interferes with the inliner in
a problematic way.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@200609 91177308-0d34-0410-b5e6-96231b3b80d8
2014-02-01 10:38:17 +00:00
Alp Toker
ae43cab6ba Fix known typos
Sweep the codebase for common typos. Includes some changes to visible function
names that were misspelt.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@200018 91177308-0d34-0410-b5e6-96231b3b80d8
2014-01-24 17:20:08 +00:00
Chandler Carruth
a7e2ef7e6e [inliner] Fix PR18206 by preventing inlining functions that call setjmp
through an invoke instruction.

The original patch for this was written by Mark Seaborn, but I've
reworked his test case into the existing returns_twice test case and
implemented the fix by the prior refactoring to actually run the cost
analysis over invoke instructions, and then here fixing our detection of
the returns_twice attribute to work for both calls and invokes. We never
noticed because we never saw an invoke. =[

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@197216 91177308-0d34-0410-b5e6-96231b3b80d8
2013-12-13 08:00:01 +00:00
Chandler Carruth
0bdc7cd5de [inliner] Completely change (and fix) how the inline cost analysis
handles terminator instructions.

The inline cost analysis inheritted some pretty rough handling of
terminator insts from the original cost analysis, and then made it much,
much worse by factoring all of the important analyses into a separate
instruction visitor. That instruction visitor never visited the
terminator.

This works fine for things like conditional branches, but for many other
things we simply computed The Wrong Value. First example are
unconditional branches, which should be free but were counted as full
cost. This is most significant for conditional branches where the
condition simplifies and folds during inlining. We paid a 1 instruction
tax on every branch in a straight line specialized path. =[

Oh, we also claimed that the unreachable instruction had cost.

But it gets worse. Let's consider invoke. We never applied the call
penalty. We never accounted for the cost of the arguments. Nope. Worse
still, we didn't handle the *correctness* constraints of not inlining
recursive invokes, or exception throwing returns_twice functions. Oops.
See PR18206. Sadly, PR18206 requires yet another fix, but this
refactoring is at least a huge step in that direction.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@197215 91177308-0d34-0410-b5e6-96231b3b80d8
2013-12-13 07:59:56 +00:00
Mark Seaborn
363c1ec574 Fix spelling in comment in test: "themselve" -> "themselves"
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@197180 91177308-0d34-0410-b5e6-96231b3b80d8
2013-12-12 21:26:30 +00:00
Mark Seaborn
34005c92bb Fix inlining to not lose the "cleanup" clause from landingpads
This fixes PR17872.  This bug can lead to C++ destructors not being
called when they should be, when an exception is thrown.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@196711 91177308-0d34-0410-b5e6-96231b3b80d8
2013-12-08 00:51:21 +00:00
Mark Seaborn
615f9b7162 Fix inlining to not produce duplicate landingpad clauses
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.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@196710 91177308-0d34-0410-b5e6-96231b3b80d8
2013-12-08 00:50:58 +00:00
Paul Robinson
fe45fd084d The 'optnone' attribute means don't inline anything into this function
(except functions marked always_inline).
Functions with 'optnone' must also have 'noinline' so they don't get
inlined into any other function.

Based on work by Andrea Di Biagio.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@195046 91177308-0d34-0410-b5e6-96231b3b80d8
2013-11-18 21:44:03 +00:00
Manman Ren
827ffff4b1 Rename testing case to use - instead of _.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@194001 91177308-0d34-0410-b5e6-96231b3b80d8
2013-11-04 18:52:06 +00:00
David Majnemer
16d1098718 Revert "Inliner: Handle readonly attribute per argument when adding memcpy"
This reverts commit r193356, it caused PR17781.

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


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@193955 91177308-0d34-0410-b5e6-96231b3b80d8
2013-11-03 12:22:13 +00:00
Manman Ren
cc14cb31d4 Add comments.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@193874 91177308-0d34-0410-b5e6-96231b3b80d8
2013-11-01 18:06:25 +00:00
Manman Ren
ef34496b3f Do not convert "call asm" to "invoke asm" in Inliner.
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


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@193808 91177308-0d34-0410-b5e6-96231b3b80d8
2013-10-31 21:56:03 +00:00
Tom Stellard
4a6b6eea2d Inliner: Handle readonly attribute per argument when adding memcpy
Patch by: Vincent Lejeune

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@193356 91177308-0d34-0410-b5e6-96231b3b80d8
2013-10-24 16:38:33 +00:00
Manman Ren
aef1b37824 TBAA: remove !tbaa from testing cases when they are not needed.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@191689 91177308-0d34-0410-b5e6-96231b3b80d8
2013-09-30 18:17:35 +00:00
Matt Arsenault
f9355c80d5 Handle address spaces in TargetTransformInfo
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@189527 91177308-0d34-0410-b5e6-96231b3b80d8
2013-08-28 22:41:57 +00:00
Daniel Dunbar
24ec2e5a72 [tests] Cleanup initialization of test suffixes.
- Instead of setting the suffixes in a bunch of places, just set one master
   list in the top-level config. We now only modify the suffix list in a few
   suites that have one particular unique suffix (.ml, .mc, .yaml, .td, .py).

 - Aside from removing the need for a bunch of lit.local.cfg files, this enables
   4 tests that were inadvertently being skipped (one in
   Transforms/BranchFolding, a .s file each in DebugInfo/AArch64 and
   CodeGen/PowerPC, and one in CodeGen/SI which is now failing and has been
   XFAILED).

 - This commit also fixes a bunch of config files to use config.root instead of
   older copy-pasted code.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@188513 91177308-0d34-0410-b5e6-96231b3b80d8
2013-08-16 00:37:11 +00:00
Tim Northover
dcef6a7400 Fix FileCheck --check-prefix lines.
Various tests had sprung up over the years which had --check-prefix=ABC on the
RUN line, but "CHECK-ABC:" later on. This happened to work before, but was
strictly incorrect. FileCheck is getting stricter soon though.

Patch by Ron Ofir.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@188173 91177308-0d34-0410-b5e6-96231b3b80d8
2013-08-12 12:43:26 +00:00
Evgeniy Stepanov
35d2102133 Disable inlining between sanitized and non-sanitized functions.
Inlining between functions with different values of sanitize_* attributes
leads to over- or under-sanitizing, which is always bad.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@187967 91177308-0d34-0410-b5e6-96231b3b80d8
2013-08-08 08:22:39 +00:00
Matt Arsenault
ff29d235ed Have InlineCost check constant fcmps
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@186758 91177308-0d34-0410-b5e6-96231b3b80d8
2013-07-20 04:09:00 +00:00
Hal Finkel
86f4f6526b Fix comparisons of alloca alignment in inliner merging
Duncan pointed out a mistake in my fix in r186425 when only one of the allocas
being compared had the target-default alignment. This is essentially his
suggested solution. Thanks!

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@186510 91177308-0d34-0410-b5e6-96231b3b80d8
2013-07-17 14:32:41 +00:00
Hal Finkel
5a5ebb7f9f When the inliner merges allocas, it must keep the larger alignment
For safety, the inliner cannot decrease the allignment on an alloca when
merging it with another.

I've included two variants of the test case for this: one with DataLayout
available, and one without. When DataLayout is not available, if only one of
the allocas uses the default alignment (getAlignment() == 0), then they cannot
be safely merged.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@186425 91177308-0d34-0410-b5e6-96231b3b80d8
2013-07-16 17:10:55 +00:00
Stephen Lin
181a289256 Fixup to r186268 and r186269: don't append -LABEL to CHECK-NOT. No functionality change.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@186271 91177308-0d34-0410-b5e6-96231b3b80d8
2013-07-14 02:10:57 +00:00
Stephen Lin
15bfd6d3ad Catch more CHECK that can be converted to CHECK-LABEL in Transforms for easier debugging. No functionality change.
This conversion was done with the following bash script:

  find test/Transforms -name "*.ll" | \
  while read NAME; do
    echo "$NAME"
    if ! grep -q "^; *RUN: *llc" $NAME; then
      TEMP=`mktemp -t temp`
      cp $NAME $TEMP
      sed -n "s/^define [^@]*@\([A-Za-z0-9_]*\)(.*$/\1/p" < $NAME | \
      while read FUNC; do
        sed -i '' "s/;\(.*\)\([A-Za-z0-9_]*\):\( *\)define\([^@]*\)@$FUNC\([( ]*\)\$/;\1\2-LABEL:\3define\4@$FUNC(/g" $TEMP
      done
      mv $TEMP $NAME
    fi
  done


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@186269 91177308-0d34-0410-b5e6-96231b3b80d8
2013-07-14 01:50:49 +00:00
Stephen Lin
39f4e8d9cc Update Transforms tests to use CHECK-LABEL for easier debugging. No functionality change.
This update was done with the following bash script:

  find test/Transforms -name "*.ll" | \
  while read NAME; do
    echo "$NAME"
    if ! grep -q "^; *RUN: *llc" $NAME; then
      TEMP=`mktemp -t temp`
      cp $NAME $TEMP
      sed -n "s/^define [^@]*@\([A-Za-z0-9_]*\)(.*$/\1/p" < $NAME | \
      while read FUNC; do
        sed -i '' "s/;\(.*\)\([A-Za-z0-9_]*\):\( *\)@$FUNC\([( ]*\)\$/;\1\2-LABEL:\3@$FUNC(/g" $TEMP
      done
      mv $TEMP $NAME
    fi
  done


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@186268 91177308-0d34-0410-b5e6-96231b3b80d8
2013-07-14 01:42:54 +00:00
Bill Wendling
46125e1a8b Update test. There may be multiple catches, but those will be cleaned up.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@177758 91177308-0d34-0410-b5e6-96231b3b80d8
2013-03-22 20:36:39 +00:00
Bill Wendling
b55b00b4d4 Update some EH tests that were violating the new EH model.
The landingpad instruction needs to be the first non-PHI instruction in the
unwind destination block.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@177650 91177308-0d34-0410-b5e6-96231b3b80d8
2013-03-21 18:30:10 +00:00
Jan Wen Voung
4323665bd8 Revert the test moves from 176733. Use "REQUIRES: asserts" instead.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@176873 91177308-0d34-0410-b5e6-96231b3b80d8
2013-03-12 16:27:52 +00:00
Jan Wen Voung
fa785cb22d Disable statistics on Release builds and move tests that depend on -stats.
Summary:
Statistics are still available in Release+Asserts (any +Asserts builds),
and stats can also be turned on with LLVM_ENABLE_STATS.

Move some of the FastISel stats that were moved under DEBUG()
back out of DEBUG(), since stats are disabled across the board now.

Many tests depend on grepping "-stats" output.  Move those into
a orig_dir/Stats/. so that they can be marked as unsupported
when building without statistics.

Differential Revision: http://llvm-reviews.chandlerc.com/D486

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@176733 91177308-0d34-0410-b5e6-96231b3b80d8
2013-03-08 22:56:31 +00:00
Jim Grosbach
186d8a3d67 InstCombine: Don't shrink allocas when combining with a bitcast.
When considering folding a bitcast of an alloca into the alloca itself,
make sure we don't shrink the amount of memory being allocated, or
things rapidly go sideways.

rdar://13324424

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@176547 91177308-0d34-0410-b5e6-96231b3b80d8
2013-03-06 05:44:53 +00:00
Bill Wendling
351b7a10e2 Use references to attribute groups on the call/invoke instructions.
Listing all of the attributes for the callee of a call/invoke instruction is way
too much and makes the IR unreadable. Use references to attributes instead.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@175877 91177308-0d34-0410-b5e6-96231b3b80d8
2013-02-22 09:09:42 +00:00
Bill Wendling
7ab6c76ad1 Modify the LLVM assembly output so that it uses references to represent function attributes.
This makes the LLVM assembly look better. E.g.:

     define void @foo() #0 { ret void }
     attributes #0 = { nounwind noinline ssp }


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@175605 91177308-0d34-0410-b5e6-96231b3b80d8
2013-02-20 07:21:42 +00:00
Bill Wendling
169d527075 Remove the AttrBuilder form of the Attribute::get creators.
The AttrBuilder is for building a collection of attributes. The Attribute object
holds only one attribute. So it's not really useful for the Attribute object to
have a creator which takes an AttrBuilder.

This has two fallouts:

1. The AttrBuilder no longer holds its internal attributes in a bit-mask form.
2. The attributes are now ordered alphabetically (hence why the tests have changed).


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@174110 91177308-0d34-0410-b5e6-96231b3b80d8
2013-01-31 23:16:25 +00:00
Bill Wendling
606c8e36df Convert getAttributes() to return an AttributeSetNode.
The AttributeSetNode contains all of the attributes. This removes one (hopefully
last) use of the Attribute class as a container of multiple attributes.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@173761 91177308-0d34-0410-b5e6-96231b3b80d8
2013-01-29 03:20:31 +00:00
Bill Wendling
114baee1fa Add the IR attribute 'sspstrong'.
SSPStrong applies a heuristic to insert stack protectors in these situations:

* A Protector is required for functions which contain an array, regardless of
  type or length.

* A Protector is required for functions which contain a structure/union which
  contains an array, regardless of type or length.  Note, there is no limit to
  the depth of nesting.

* A protector is required when the address of a local variable (i.e., stack
  based variable) is exposed. (E.g., such as through a local whose address is
  taken as part of the RHS of an assignment or a local whose address is taken as
  part of a function argument.)

This patch implements the SSPString attribute to be equivalent to
SSPRequired. This will change in a subsequent patch.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@173230 91177308-0d34-0410-b5e6-96231b3b80d8
2013-01-23 06:41:41 +00:00
Dmitri Gribenko
3dd0781b8c Tests: rewrite 'opt ... %s' to 'opt ... < %s' so that opt does not emit a ModuleID
This is done to avoid odd test failures, like the one fixed in r171243.

While there, FileCheck'ize tests.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@171344 91177308-0d34-0410-b5e6-96231b3b80d8
2013-01-01 14:04:36 +00:00
Dmitri Gribenko
fbfb1b286f Tests: rewrite 'opt ... %s' to 'opt ... < %s' so that opt does not emit a ModuleID
This is done to avoid odd test failures, like the one fixed in r171243.

My previous regex was not good enough to find these.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@171343 91177308-0d34-0410-b5e6-96231b3b80d8
2013-01-01 13:57:25 +00:00
Dmitri Gribenko
a6542923b8 Tests: rewrite 'opt ... %s' to 'opt ... < %s' so that opt does not emit a ModuleID
This is done to avoid odd test failures, like the one fixed in r171243.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@171250 91177308-0d34-0410-b5e6-96231b3b80d8
2012-12-30 02:33:22 +00:00
Dmitri Gribenko
b4912b9dcc Tests: rewrite 'opt ... %s' to 'opt ... < %s' so that opt does not emit a ModuleID
This is done to avoid odd test failures, like the one fixed in r171243.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@171246 91177308-0d34-0410-b5e6-96231b3b80d8
2012-12-30 01:28:40 +00:00
Chandler Carruth
73527d30cd Fix a stunning oversight in the inline cost analysis. It was never
propagating one of the values it simplified to a constant across
a myriad of instructions. Notably, ptrtoint instructions when we had
a constant pointer (say, 0) didn't propagate that, blocking a massive
number of down-stream optimizations.

This was uncovered when investigating why we fail to inline and delete
the boilerplate in:

  void f() {
    std::vector<int> v;
    v.push_back(1);
  }

It turns out most of the efforts I've made thus far to improve the
analysis weren't making it far purely because of this. After this is
fixed, the store-to-load forwarding patch enables LLVM to optimize the
above to an empty function. We still can't nuke a second push_back, but
for different reasons.

There is a very real chance this will cause somewhat noticable changes
in inlining behavior, so please let me know if you see regressions (or
improvements!) because of this patch.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@171196 91177308-0d34-0410-b5e6-96231b3b80d8
2012-12-28 14:43:42 +00:00