Summary:
When alias analysis is uncertain about the aliasing between any two accesses,
it will return MayAlias. This uncertainty from alias analysis restricts LICM
from proceeding further. In cases where alias analysis is uncertain we might
use loop versioning as an alternative.
Loop Versioning will create a version of the loop with aggressive aliasing
assumptions in addition to the original with conservative (default) aliasing
assumptions. The version of the loop making aggressive aliasing assumptions
will have all the memory accesses marked as no-alias. These two versions of
loop will be preceded by a memory runtime check. This runtime check consists
of bound checks for all unique memory accessed in loop, and it ensures the
lack of memory aliasing. The result of the runtime check determines which of
the loop versions is executed: If the runtime check detects any memory
aliasing, then the original loop is executed. Otherwise, the version with
aggressive aliasing assumptions is used.
The pass is off by default and can be enabled with command line option
-enable-loop-versioning-licm.
Reviewers: hfinkel, anemet, chatur01, reames
Subscribers: MatzeB, grosser, joker.eph, sanjoy, javed.absar, sbaranga,
llvm-commits
Differential Revision: http://reviews.llvm.org/D9151
llvm-svn: 259986
In r255133 (reapplied r253126) we started to avoid redundant
recomputation of LCSSA after loop-unrolling. This patch moves one step
further in this direction - now we can avoid it for much wider range of
loops, as we start to look at IR and try to figure out if the
transformation actually breaks LCSSA phis or makes it necessary to
insert new ones.
Differential Revision: http://reviews.llvm.org/D16838
llvm-svn: 259869
Summary:
Passing the rematerialized values map to insertRematerializationStores by
value looks to be a simple oversight; update it to pass by reference.
Reviewers: reames, sanjoy
Subscribers: llvm-commits
Differential Revision: http://reviews.llvm.org/D16911
llvm-svn: 259867
Current SCEV expansion will expand SCEV as a sequence of operations
and doesn't utilize the value already existed. This will introduce
redundent computation which may not be cleaned up throughly by
following optimizations.
This patch introduces an ExprValueMap which is a map from SCEV to the
set of equal values with the same SCEV. When a SCEV is expanded, the
set of values is checked and reused whenever possible before generating
a sequence of operations.
The original commit triggered regressions in Polly tests. The regressions
exposed two problems which have been fixed in current version.
1. Polly will generate a new function based on the old one. To generate an
instruction for the new function, it builds SCEV for the old instruction,
applies some tranformation on the SCEV generated, then expands the transformed
SCEV and insert the expanded value into new function. Because SCEV expansion
may reuse value cached in ExprValueMap, the value in old function may be
inserted into new function, which is wrong.
In SCEVExpander::expand, there is a logic to check the cached value to
be used should dominate the insertion point. However, for the above
case, the check always passes. That is because the insertion point is
in a new function, which is unreachable from the old function. However
for unreachable node, DominatorTreeBase::dominates thinks it will be
dominated by any other node.
The fix is to simply add a check that the cached value to be used in
expansion should be in the same function as the insertion point instruction.
2. When the SCEV is of scConstant type, expanding it directly is cheaper than
reusing a normal value cached. Although in the cached value set in ExprValueMap,
there is a Constant type value, but it is not easy to find it out -- the cached
Value set is not sorted according to the potential cost. Existing reuse logic
in SCEVExpander::expand simply chooses the first legal element from the cached
value set.
The fix is that when the SCEV is of scConstant type, don't try the reuse
logic. simply expand it.
Differential Revision: http://reviews.llvm.org/D12090
llvm-svn: 259736
D16251)
Summary:
This is a simpler fix to the problem than the dominator approach in
http://reviews.llvm.org/D16251. It adds only values into the gather() while loop
that have been seen before.
The actual endless loop is in the constant compare gather() routine in
Utils/SimplifyCFG.cpp. The same value ret.0.off0.i is pushed back into the
queue:
%.ret.0.off0.i = or i1 %.ret.0.off0.i, %cmp10.i
Here is what happens at the IR level:
for.cond.i: ; preds = %if.end6.i,
%if.end.i54
%ix.0.i = phi i32 [ 0, %if.end.i54 ], [ %inc.i55, %if.end6.i ]
%ret.0.off0.i = phi i1 [false, %if.end.i54], [%.ret.0.off0.i, %if.end6.i] <<<
%cmp2.i = icmp ult i32 %ix.0.i, %11
br i1 %cmp2.i, label %for.body.i, label %LBJ_TmpSimpleNeedExt.exit
if.end6.i: ; preds = %for.body.i
%cmp10.i = icmp ugt i32 %conv.i, %add9.i
%.ret.0.off0.i = or i1 %ret.0.off0.i, %cmp10.i <<<
When if.end.i54 gets eliminated which removes the definition of ret.0.off0.i.
The result is the expression %.ret.0.off0.i = or i1 %.ret.0.off0.i, %cmp10.i
(Note the first ‘or’ operand is now %.ret.0.off0.i, and *NOT* %ret.0.off0.i).
And
now there is use of .ret.0.off0.i before a definition which triggers the
“endless” loop in gather():
while(!DFT.empty()) {
V = DFT.pop_back_val(); // V is .ret.0.off0.i
if (Instruction *I = dyn_cast<Instruction>(V)) {
// If it is a || (or && depending on isEQ), process the operands.
if (I->getOpcode() == (isEQ ? Instruction::Or : Instruction::And)) {
DFT.push_back(I->getOperand(1)); // This is now .ret.0.off0.i also
DFT.push_back(I->getOperand(0));
continue; // “endless loop” for .ret.0.off0.i
}
Reviewers: reames, ahatanak
Subscribers: llvm-commits
Differential Revision: http://reviews.llvm.org/D16839
llvm-svn: 259730
Bail out if we have a PHI on an EHPad that gets a value from a
CatchSwitchInst. Because the CatchSwitchInst cannot be split, there is
no good place to stick any instructions.
This fixes PR26373.
llvm-svn: 259702
According to git bisect, this is the root cause of a miscompile for Regex in
libLLVMSupport. I am still working on reducing a test case.
The actual bug may be elsewhere and this commit just exposed it.
Anyway, at the moment, to reproduce, follow these steps:
1. Build clang and libLTO in release mode.
2. Create a new build directory <stage2> and cd into it.
3. Use clang and libLTO from #1 to build llvm-extract in Release mode + asserts
using -O2 -flto
4. Run llvm-extract -ralias '.*bar' -S test/Other/extract-alias.ll
Result:
program doesn't contain global named '.*bar'!
Expected result:
@a0a0bar = alias void ()* @bar
@a0bar = alias void ()* @bar
declare void @bar()
Note: In step #3, if you don't use lto or asserts, the miscompile disappears.
llvm-svn: 259674
Current SCEV expansion will expand SCEV as a sequence of operations
and doesn't utilize the value already existed. This will introduce
redundent computation which may not be cleaned up throughly by
following optimizations.
This patch introduces an ExprValueMap which is a map from SCEV to the
set of equal values with the same SCEV. When a SCEV is expanded, the
set of values is checked and reused whenever possible before generating
a sequence of operations.
Differential Revision: http://reviews.llvm.org/D12090
llvm-svn: 259662
Summary:
LoopVersioning is a transform utility that transform passes can use to
run-time disambiguate may-aliasing accesses. I'd like to also expose as
pass to allow it to be unit-tested.
I am planning to add support for non-aliasing annotation in
LoopVersioning and I'd like to be able to write tests directly using
this pass.
(After that feature is done, the pass could also be used to look for
optimization opportunities that are hidden behind incomplete alias
information at compile time.)
The pass drives LoopVersioning in its default way which is to fully
disambiguate may-aliasing accesses no matter how many checks are
required.
Reviewers: hfinkel, ashutosh.nema, sbaranga
Subscribers: zzheng, mssimpso, llvm-commits, sanjoy
Differential Revision: http://reviews.llvm.org/D16612
llvm-svn: 259610
Please see include/llvm/Transforms/Utils/MemorySSA.h for a description
of MemorySSA, and what it does.
Differential Revision: http://reviews.llvm.org/D7864
llvm-svn: 259595
A masked store with a zero mask means there's no store.
A masked store with an allOnes mask means it's a normal vector store.
This is a continuation of:
http://reviews.llvm.org/rL259369
llvm-svn: 259392
This miscompile came about because we tried to use a transform which was
only appropriate for xor operators when addition was present.
This fixes PR26407.
llvm-svn: 259375
A masked load with a zero mask means there's no load.
A masked load with an allOnes mask means it's a normal vector load.
Differential Revision: http://reviews.llvm.org/D16691
llvm-svn: 259369
In the future, we will vectorize recurrences other than reductions. This patch
renames a few variables and updates their associated comments to enable them to
be reused for non-reduction PHI nodes.
This change was requested in the review for D16197.
llvm-svn: 259364
Loop transformations can sometimes fail because the loop, while in
valid rotated LCSSA form, is not in a canonical CFG form. This is
an extremely simple pass that just merges obviously redundant
blocks, which can be used to fix some known failure cases. In the
future, it may be enhanced with more cases (and have code shared with
SimplifyCFG).
This allows us to run LoopSimplifyCFG -> LoopRotate -> LoopUnroll,
so that SimplifyCFG cleans up the loop before Rotate tries to run.
Not currently used in the pass manager, since this pass doesn't do
anything unless you can hook it up in an LPM with other loop passes.
It'll be added once Chandler cleans up things to allow this.
Tested in a custom pipeline out of tree to confirm it works in
practice (in addition to the included trivial test).
llvm-svn: 259256
We would infinite loop because we created a shufflevector that was wider than
needed and then failed to combine that with the insertelement. When subsequently
visiting the extractelement from that shuffle, we see that it's unnecessary,
delete it, and trigger another visit to the insertelement.
llvm-svn: 259236
- Locally declare struct, and call it BaseDerivedPair
- Use a lambda to compare, instead of a singleton with uninitialized
fields
- Add a constructor to BaseDerivedPair and use SmallVector::emplace_back
llvm-svn: 259208
The full diff for the test directory may be hard to read because of the
filename clash; so here's all that happened as far as the tests are
concerned:
```
cd test/Transforms/RewriteStatepointsForGC
git rm *ll
git mv deopt-bundles/* ./
rmdir deopt-bundles
find . -name '*.ll' | xargs gsed -i 's/-rs4gc-use-deopt-bundles //g'
```
llvm-svn: 259129
These changes are aimed at bringing PlaceSafepoints up to code with the
LLVM coding guidelines:
- Fix variable naming
- Use DenseSet instead of std::set
- Remove dead code
- Minor local code simplifications
llvm-svn: 259112
This change permanently clamps -spp-no-statepoints to true (the code
deletion will come later). Tests that specifically tested
PlaceSafepoint's ability to wrap calls in gc.statepoint have been moved
to RS4GC's test suite.
llvm-svn: 259096
Summary: When splitting module with preserving locals, we currently do not handle case of global alias being separated with its aliasee.
Subscribers: llvm-commits
Differential Revision: http://reviews.llvm.org/D16585
llvm-svn: 259075
Summary:
If the instruction we're hoisting out of a loop into its preheader is
guaranteed to have executed in the loop, then the metadata associated
with the instruction (e.g. !range or !dereferenceable) is valid in the
preheader. This is because once we're in the preheader, we know we're
eventually going to reach the location the metadata was valid at.
This change makes LICM smarter around this, and helps it recognize cases
like these:
```
do {
int a = *ptr; !range !0
...
} while (i++ < N);
```
to
```
int a = *ptr; !range !0
do {
...
} while (i++ < N);
```
Earlier we'd drop the `!range` metadata after hoisting the load from
`ptr`.
Reviewers: igor-laevsky
Subscribers: mcrosier, llvm-commits
Differential Revision: http://reviews.llvm.org/D16669
llvm-svn: 259053
This is a fix for:
https://llvm.org/bugs/show_bug.cgi?id=26308
With the switch to using the TTI cost model in:
http://reviews.llvm.org/rL228826
...it became possible to hit a zero-cost cycle of instructions (gep -> phi -> gep...),
so we need a cap for the recursion in DominatesMergePoint().
A recursion depth parameter was already added for a different reason in:
http://reviews.llvm.org/rL255660
...so we can just set a limit for it.
I pulled "10" out of the air and made it an independent parameter that we can play with.
It might be higher than it needs to be given the currently low default value of
PHINodeFoldingThreshold (2). That's the starting cost value that we enter the recursion
with, and most instructions have cost set to TCC_Basic (1), so I don't think we're going
to speculate more than 2 instructions with the current parameters.
As noted in the review and the TODO comment, we can do better than just limiting recursion
depth.
Differential Revision: http://reviews.llvm.org/D16637
llvm-svn: 258971
ObjC ARC Optimizer.
The main implication of this is:
1. Ensuring that we treat it conservatively in terms of optimization.
2. We put the ASM marker on it so that the runtime can recognize
objc_unsafeClaimAutoreleasedReturnValue from releaseRV.
<rdar://problem/21567064>
Patch by Michael Gottesman!
llvm-svn: 258970
This patch is the second attempt to reapply commit r258404. There was bug in
the initial patch and subsequent fix (mentioned below).
The initial patch caused an assertion because we were computing smaller type
sizes for instructions that cannot be demoted. The fix first determines the
instructions that will be demoted, and then applies the smaller type size to
only those instructions.
This should fix PR26239 and PR26307.
llvm-svn: 258929
Summary:
This is a revised version of D13974, and the following quoted summary are from D13974
"This patch adds support to check if a loop has loop invariant conditions which lead to loop exits. If so, we know that if the exit path is taken, it is at the first loop iteration. If there is an induction variable used in that exit path whose value has not been updated, it will keep its initial value passing from loop preheader. We can therefore rewrite the exit value with
its initial value. This will help remove phis created by LCSSA and enable other optimizations like loop unswitch."
D13974 was committed but failed one lnt test. The bug was that we only checked the condition from loop exit's incoming block was a loop invariant. But there could be another condition from loop header to that incoming block not being a loop invariant. This would produce miscompiled code.
This patch fixes the issue by checking if the incoming block is loop header, and if not, don't perform the rewrite. The could be further improved by recursively checking all conditions leading to loop exit block, but I'd like to check in this simple version first and improve it with future patches.
Reviewers: sanjoy
Subscribers: llvm-commits
Differential Revision: http://reviews.llvm.org/D16570
llvm-svn: 258912
SimplifyCFG tries to turn complex branch conditions into a switch.
Some of it's logic attempts to reason about bitwise arithmetic produced
by InstCombine. InstCombine can turn things like (X == 2) || (X == 3)
into (X & 1) == 2 and so SimplifyCFG tries to detect when this occurs so
that it can produce a switch instruction.
However, the legality checking was not sufficient to determine whether
or not this had occured. Correctly check this case by requiring that
the right-hand side of the comparison be a power of two.
This fixes PR26323.
llvm-svn: 258904
AvailableValue is the part that represents the potential rematerialization. AvailableValueInBlock is simply a pair of an AvailableValue and a BB which we might materialize it in.
This is motivated by http://reviews.llvm.org/D16608. The intent is that we'll have a single function which handles the local case which both local and non-local will use to identify available values. Once that's done, the local case can rematerialize at the use site and the non-local case can do the SSA construction as it does currently.
llvm-svn: 258882
Summary:
This patch is provided in preparation for removing autoconf on 1/26. The proposal to remove autoconf on 1/26 was discussed on the llvm-dev thread here: http://lists.llvm.org/pipermail/llvm-dev/2016-January/093875.html
"I felt a great disturbance in the [build system], as if millions of [makefiles] suddenly cried out in terror and were suddenly silenced. I fear something [amazing] has happened."
- Obi Wan Kenobi
Reviewers: chandlerc, grosbach, bob.wilson, tstellarAMD, echristo, whitequark
Subscribers: chfast, simoncook, emaste, jholewinski, tberghammer, jfb, danalbert, srhines, arsenm, dschuff, jyknight, dsanders, joker.eph, llvm-commits
Differential Revision: http://reviews.llvm.org/D16471
llvm-svn: 258861
Previously the RedoInsts was processed at the end of the block.
However it was possible that it left behind some instructions that
were not canonicalized.
This should guarantee that any previous instruction in the basic
block is canonicalized before we process a new instruction.
llvm-svn: 258830
This is a step towards solving PR25892:
https://llvm.org/bugs/show_bug.cgi?id=25892
It won't handle the reported case. As noted by the 'TODO' comments in the patch,
we need to relax the hasOneUse() constraint and also match patterns that include
memset_chk() and the llvm.memset() intrinsic in addition to memset().
Differential Revision: http://reviews.llvm.org/D16337
llvm-svn: 258816
This commit exposes a crash in computeKnownBits on the Chromium buildbots.
Reverting to investigate.
Reference: https://llvm.org/bugs/show_bug.cgi?id=26307
llvm-svn: 258812
This is a recommit of r258620 which causes PR26293.
The original message:
Now LIR can turn following codes into memset:
typedef struct foo {
int a;
int b;
} foo_t;
void bar(foo_t *f, unsigned n) {
for (unsigned i = 0; i < n; ++i) {
f[i].a = 0;
f[i].b = 0;
}
}
void test(foo_t *f, unsigned n) {
for (unsigned i = 0; i < n; i += 2) {
f[i] = 0;
f[i+1] = 0;
}
}
llvm-svn: 258777
* __cfi_check gets a 3rd argument: ubsan handler data
* Instead of trapping on failure, call __cfi_check_fail which must be
present in the module (generated in the frontend).
llvm-svn: 258746
We had the same code duplicated for each type of Def. We also have the entire block duplicated between the local and non-local case, but let's start with local cleanup.
llvm-svn: 258740
We were hitting an assertion because we were computing smaller type sizes for
instructions that cannot be demoted. The fix first determines the instructions
that will be demoted, and then applies the smaller type size to only those
instructions.
This should fix PR26239.
llvm-svn: 258705
Use existing functionality provided in changeToUnreachable instead of
reinventing it in LoopSimplify.
No functionality change is intended.
llvm-svn: 258663
SCCP has code identical to changeToUnreachable's behavior, switch it
over to just call changeToUnreachable.
No functionality change intended.
llvm-svn: 258654
InstCombine and SCCP both want to remove dead code in a very particular
way but using identical means to do so. Share the code between the two.
No functionality change is intended.
llvm-svn: 258653
The intrinsic target prefix should match the target name
as it appears in the triple.
This is not yet complete, but gets most of the important ones.
llvm.AMDGPU.* intrinsics used by mesa and libclc are still handled
for compatability for now.
llvm-svn: 258557
Summary:
Make sure that any new and optimized objects created during GlobalOPT copy all the attributes from the base object.
A good example of improper behavior in the current implementation is section information associated with the GlobalObject. If a section was set for it, and GlobalOpt is creating/modifying a new object based on this one (often copying the original name), without this change new object will be placed in a default section, resulting in inappropriate properties of the new variable.
The argument here is that if customer specified a section for a variable, any changes to it that compiler does should not cause it to change that section allocation.
Moreover, any other properties worth representation in copyAttributesFrom() should also be propagated.
Reviewers: jmolloy, joker-eph, joker.eph
Subscribers: slarin, joker.eph, rafael, tobiasvk, llvm-commits
Differential Revision: http://reviews.llvm.org/D16074
llvm-svn: 258556
Summary:
This change adds a `-spp-no-statepoints` flag to PlaceSafepoints that
bypasses the code that wraps newly introduced polls and existing calls
in gc.statepoint. With `-spp-no-statepoints` enabled, PlaceSafepoints
effectively becomes a safpeoint **poll** insertion pass.
The eventual goal is to "constant fold" this option, along with
`-rs4gc-use-deopt-bundles` to `true`, once clients using gc.statepoint
are okay doing so.
Reviewers: pgavlin, reames, JosephTremoulet
Subscribers: sanjoy, mcrosier, llvm-commits
Differential Revision: http://reviews.llvm.org/D16439
llvm-svn: 258551
Summary:
Since we are currently not doing incremental importing there is
no need to link metadata as a postpass. The module linker will
only link in the imported subroutines due to the functionality
added by r256003.
(Note that the metadata postpass linking functionalitiy is still
used by llvm-link, and may be needed here in the future if a more
incremental strategy is adopted.)
Reviewers: joker.eph
Subscribers: joker.eph, llvm-commits
Differential Revision: http://reviews.llvm.org/D16424
llvm-svn: 258458
Use the helper function added in r258428.
The check should really be hoisted to the caller of all of these
optimize* functions, but that's another step.
llvm-svn: 258446
This is similar to the bug/fix:
https://llvm.org/bugs/show_bug.cgi?id=26211http://reviews.llvm.org/rL258325
The fmin() test case reveals another bug caused by sloppy
code duplication. It will crash without this patch because
fp128 is a valid floating-point type, but we would think
that we had matched a function that used doubles.
The new helper function can be used to replace similar
checks that are used in several other places in this file.
llvm-svn: 258428
This patch includes the passmanagerbuilder change that enables IR level PGO instrumentation. It adds two passmanagerbuilder options: -profile-generate=<profile_filename> and -profile-use=<profile_filename>. The new options are primarily for debug purpose.
Reviewers: davidxl, silvas
Differential Revision: http://reviews.llvm.org/D15828
llvm-svn: 258420
This patch adds the instrumentation for indirect call value profiling. It finds all the indirect call-sites and generates instrprof_value_profile intrinsic calls. A new opt level option -disable-vp is introduced to disable this instrumentation.
Reviewers: davidxl, betulb, vsk
Differential Revision: http://reviews.llvm.org/D16016
llvm-svn: 258417
Do not emit profile arc files and note files for module and skeleton
CU's.
Our users report seeing unexpected *.gcda and *.gcno files in their
projects when using gcov-style profiling with modules or frameworks.
The unwanted files come from these modules. This is not very helpful
for end-users. Further, we've seen reports of instrumented programs
crashing while writing these files out (due to I/O failures).
rdar://problem/22838296
Reviewed-by: aprantl
Differential Revision: http://reviews.llvm.org/D15997
llvm-svn: 258406
This change attempts to produce vectorized integer expressions in bit widths
that are narrower than their scalar counterparts. The need for demotion arises
especially on architectures in which the small integer types (e.g., i8 and i16)
are not legal for scalar operations but can still be used in vectors. Like
similar work done within the loop vectorizer, we rely on InstCombine to perform
the actual type-shrinking. We use the DemandedBits analysis and
ComputeNumSignBits from ValueTracking to determine the minimum required bit
width of an expression.
Differential revision: http://reviews.llvm.org/D15815
llvm-svn: 258404
Summary:
The previous form, taking opcode and type, is moved to an internal
helper and the new form, taking an instruction, is a wrapper around this
helper.
Although this is a slight cleanup on its own, the main motivation is to
refactor the constant folding API to ease migration to opaque pointers.
This will be follow-up work.
Reviewers: eddyb
Subscribers: dblaikie, llvm-commits
Differential Revision: http://reviews.llvm.org/D16383
llvm-svn: 258391
Summary:
This adds a new kind of operand bundle to LLVM denoted by the
`"gc-transition"` tag. Inputs to `"gc-transition"` operand bundle are
lowered into the "transition args" section of `gc.statepoint` by
`RewriteStatepointsForGC`.
This removes the last bit of functionality that was unsupported in the
deopt bundle based code path in `RewriteStatepointsForGC`.
Reviewers: pgavlin, JosephTremoulet, reames
Subscribers: sanjoy, mcrosier, llvm-commits
Differential Revision: http://reviews.llvm.org/D16342
llvm-svn: 258338
The test case will crash without this patch because the subsequent call to
hasUnsafeAlgebra() assumes that the call instruction is an FPMathOperator
(ie, returns an FP type).
This part of the function signature check was omitted for the sqrt() case,
but seems to be in place for all other transforms.
Before:
http://reviews.llvm.org/rL257400
...we would have needlessly continued execution in optimizeSqrt(), but the
bug was harmless because we'd eventually fail some other check and return
without damage.
This should fix:
https://llvm.org/bugs/show_bug.cgi?id=26211
Differential Revision: http://reviews.llvm.org/D16198
llvm-svn: 258325
Summary:
Funclet EH tables require that a given funclet have only one unwind
destination for exceptional exits. The verifier will therefore reject
e.g. two cleanuprets with different unwind dests for the same cleanup, or
two invokes exiting the same funclet but to different unwind dests.
Because catchswitch has no 'nounwind' variant, and because IR producers
are not *required* to annotate calls which will not unwind as 'nounwind',
it is legal to nest a call or an "unwind to caller" catchswitch within a
funclet pad that has an unwind destination other than caller; it is
undefined behavior for such a call or catchswitch to unwind.
Normally when inlining an invoke, calls in the inlined sequence are
rewritten to invokes that unwind to the callsite invoke's unwind
destination, and "unwind to caller" catchswitches in the inlined sequence
are rewritten to unwind to the callsite invoke's unwind destination.
However, if such a call or "unwind to caller" catchswitch is located in a
callee funclet that has another exceptional exit with an unwind
destination within the callee, applying the normal transformation would
give that callee funclet multiple unwind destinations for its exceptional
exits. There would be no way for EH table generation to determine which
is the "true" exit, and the verifier would reject the function
accordingly.
Add logic to the inliner to detect these cases and leave such calls and
"unwind to caller" catchswitches as calls and "unwind to caller"
catchswitches in the inlined sequence.
This fixes PR26147.
Reviewers: rnk, andrew.w.kaylor, majnemer
Subscribers: alexcrichton, llvm-commits
Differential Revision: http://reviews.llvm.org/D16319
llvm-svn: 258273
This patch creates the profile data variable before lowering the profile intrinsics.
Reviewers: davidxl, silvas
Differential Revision: http://reviews.llvm.org/D16015
llvm-svn: 258156
This is a continuation of adding FMF to call instructions:
http://reviews.llvm.org/rL255555
As with D15937, the intent of the patch is to preserve the current behavior of the transform
except that we use the pow call's 'fast' attribute as a trigger rather than a function-level
attribute.
The TODO comment notes a potential follow-on patch that would propagate FMF to the new
instructions.
Differential Revision: http://reviews.llvm.org/D16122
llvm-svn: 258153
Summary:
GEPOperator: provide getResultElementType alongside getSourceElementType.
This is made possible by adding a result element type field to GetElementPtrConstantExpr, which GetElementPtrInst already has.
GEP: replace get(Pointer)ElementType uses with get{Source,Result}ElementType.
Reviewers: mjacob, dblaikie
Subscribers: llvm-commits
Differential Revision: http://reviews.llvm.org/D16275
llvm-svn: 258145
This commit changes the default on our lowering of vectors-of-pointers from splitting in RS4GC to reporting them in the final stack map. All of the changes to do so are already in place and tested. Assuming no problems are unearthed in the next week, we will be deleting the old code entirely next Monday.
llvm-svn: 258111
Summary:
Currently llvm::SplitModule as the first step globalizes all local objects, which might not be desirable in some scenarios.
This change adds a new flag to llvm::SplitModule that uses SCC approach to search for a balanced partition without the need to externalize symbols.
Such partition might not be possible or fully balanced for a given number of partitions, and is a function of the module properties (global/local dependencies within the module).
Joint development Tobias Edler von Koch (tobias@codeaurora.org) and Sergei Larin (slarin@codeaurora.org)
Subscribers: llvm-commits, joker.eph
Differential Revision: http://reviews.llvm.org/D16124
llvm-svn: 258083
This is part of a new statistics gathering feature for the sanitizers.
See clang/docs/SanitizerStats.rst for further info and docs.
Differential Revision: http://reviews.llvm.org/D16174
llvm-svn: 257970
I mentioned the issue here in code review way back in September and
was sure we'd fixed it, but apparently we forgot:
http://lists.llvm.org/pipermail/llvm-commits/Week-of-Mon-20150921/301850.html
In any case, as soon as you try to use this pass in anything but the
most basic pipeline everything falls apart. Fix the condition.
llvm-svn: 257935
The fix uniques the bundle of getelementptr indices we are about to vectorize
since it's possible for the same index to be used by multiple instructions.
The original commit message is below.
[SLP] Vectorize the index computations of getelementptr instructions.
This patch seeds the SLP vectorizer with getelementptr indices. The primary
motivation in doing so is to vectorize gather-like idioms beginning with
consecutive loads (e.g., g[a[0] - b[0]] + g[a[1] - b[1]] + ...). While these
cases could be vectorized with a top-down phase, seeding the existing bottom-up
phase with the index computations avoids the complexity, compile-time, and
phase ordering issues associated with a full top-down pass. Only bundles of
single-index getelementptrs with non-constant differences are considered for
vectorization.
llvm-svn: 257918
platforms.
With ELF, the alignment of a global variable in a shared library will
get copied into an executables linked against it, if the executable even
accesss the variable. So, it's not possible to implicitly increase
alignment based on access patterns, or you'll break existing binaries.
This happened to affect libc++'s std::cout symbol, for example. See
thread: http://thread.gmane.org/gmane.comp.compilers.clang.devel/45311
(This is a re-commit of r257719, without the bug reported in
PR26144. I've tweaked the code to not assert-fail in
enforceKnownAlignment when computeKnownBits doesn't recurse far enough
to find the underlying Alloca/GlobalObject value.)
Differential Revision: http://reviews.llvm.org/D16145
llvm-svn: 257902
This contains a fix for the issue that caused the revert:
we no longer assume that we can insert instructions after the
instruction that produces the base pointer. We previously
assumed that this would be ok, because the instruction produces
a value and therefore is not a terminator. This is false for invoke
instructions. We will now insert these new instruction directly
at the location of the users.
Original commit message:
[InstCombine] Look through PHIs, GEPs, IntToPtrs and PtrToInts to expose more constants when comparing GEPs
Summary:
When comparing two GEP instructions which have the same base pointer
and one of them has a constant index, it is possible to only compare
indices, transforming it to a compare with a constant. This removes
one use for the GEP instruction with the constant index, can reduce
register pressure and can sometimes lead to removing the comparisson
entirely.
InstCombine was already doing this when comparing two GEPs if the base
pointers were the same. However, in the case where we have complex
pointer arithmetic (GEPs applied to GEPs, PHIs of GEPs, conversions to
or from integers, etc) the value of the original base pointer will be
hidden to the optimizer and this transformation will be disabled.
This change detects when the two sides of the comparison can be
expressed as GEPs with the same base pointer, even if they don't
appear as such in the IR. The transformation will convert all the
pointer arithmetic to arithmetic done on indices and all the relevant
uses of GEPs to GEPs with a common base pointer. The GEP comparison
will be converted to a comparison done on indices.
Reviewers: majnemer, jmolloy
Subscribers: hfinkel, jevinskie, jmolloy, aadg, llvm-commits
Differential Revision: http://reviews.llvm.org/D15146
llvm-svn: 257897
There are several requirements that ended up with this design;
1. Matching bitreversals is too heavyweight for InstCombine and doesn't really need to be done so early.
2. Bitreversals and byteswaps are very related in their matching logic.
3. We want to implement support for matching more advanced bswap/bitreverse patterns like partial bswaps/bitreverses.
4. Bswaps are best matched early in InstCombine.
The result of these is that a new utility function is created in Transforms/Utils/Local.h that can be configured to search for bswaps, bitreverses or both. InstCombine uses it to find only bswaps, CGP uses it to find only bitreversals.
We can then extend the matching logic in one place only.
llvm-svn: 257875
This patch seeds the SLP vectorizer with getelementptr indices. The primary
motivation in doing so is to vectorize gather-like idioms beginning with
consecutive loads (e.g., g[a[0] - b[0]] + g[a[1] - b[1]] + ...). While these
cases could be vectorized with a top-down phase, seeding the existing bottom-up
phase with the index computations avoids the complexity, compile-time, and
phase ordering issues associated with a full top-down pass. Only bundles of
single-index getelementptrs with non-constant differences are considered for
vectorization.
Differential Revision: http://reviews.llvm.org/D14829
llvm-svn: 257800
Summary: If SROA creates only one piece (e.g. because the other is not needed),
it still needs to create a bit_piece expression if that bit piece is smaller
than the original size of the alloca.
Reviewers: aprantl
Subscribers: llvm-commits
Differential Revision: http://reviews.llvm.org/D16187
llvm-svn: 257795
Summary: The dbg.declare -> dbg.value conversion did not check which operand of
the store instruction the alloca was passed to. As a result code that stored the
address of an alloca, rather than storing to the alloca, would still trigger
the conversion routine, leading to the insertion of an incorrect dbg.value
intrinsic.
Reviewers: aprantl
Subscribers: llvm-commits
Differential Revision: http://reviews.llvm.org/D16169
llvm-svn: 257787
Loop trip counts can often be resolved during LTO. We should obviously be unrolling small loops once those trip counts have been resolved, but we weren't.
llvm-svn: 257767
Summary:
The overloads of CallInst::Create and InvokeInst::Create that are used to
adjust operand bundles purport to create a new instruction "identical in
every way except [for] the operand bundles", so copy the DebugLoc along
with everything else.
Reviewers: sanjoy, majnemer
Subscribers: majnemer, dblaikie, llvm-commits
Differential Revision: http://reviews.llvm.org/D16157
llvm-svn: 257745
platforms.
With ELF, the alignment of a global variable in a shared library will
get copied into an executables linked against it, if the executable even
accesss the variable. So, it's not possible to implicitly increase
alignment based on access patterns, or you'll break existing binaries.
This happened to affect libc++'s std::cout symbol, for example. See
thread: http://thread.gmane.org/gmane.comp.compilers.clang.devel/45311
llvm-svn: 257719
Summary: The dbg.declare -> dbg.value conversion looks through any zext/sext
to find a value to describe the variable (in the expectation that those
zext/sext instruction will go away later). However, those values do not
cover the entire variable and thus need a DW_OP_bit_piece.
Reviewers: aprantl
Subscribers: llvm-commits
Differential Revision: http://reviews.llvm.org/D16061
llvm-svn: 257534
The findExternalCalls routine ignores calls to functions already
defined in the dest module. This was not handling the case where
the definition in the current module is actually an alias to a
function call.
llvm-svn: 257493
The layering of where the various loop unroll parameters are
initialized and overridden here was very confusing, making it pretty
difficult to tell just how the various sources interacted. Instead, we
put all of the initialization logic together in a single function so
that it's obvious what overrides what.
llvm-svn: 257426
Currently we're unrolling loops more in minsize than in optsize, which
means -Oz will have a larger code size than -Os. That doesn't make any
sense.
This resolves the FIXME about this in LoopUnrollPass and extends the
optsize test to make sure we use the smaller threshold for minsize as
well.
llvm-svn: 257402
This is a continuation of adding FMF to call instructions:
http://reviews.llvm.org/rL255555
The intent of the patch is to preserve the current behavior of the transform except
that we use the sqrt instruction's 'fast' attribute as a trigger rather than the
function-level attribute.
But this raises a bug noted by the new FIXME comment.
In order to do this transform:
sqrt((x * x) * y) ---> fabs(x) * sqrt(y)
...we need all of the sqrt, the first fmul, and the second fmul to be 'fast'.
If any of those ops is strict, we should bail out.
Differential Revision: http://reviews.llvm.org/D15937
llvm-svn: 257400
Address review feedback from r255909.
Move body of resolveCycles(bool AllowTemps) to
resolveRecursivelyImpl(bool AllowTemps). Revert resolveCycles back
to asserting on temps, and add new resolveNonTemporaries interface
to invoke the new implementation with AllowTemps=true. Document
the differences between these interfaces, specifically the effect
on RAUW support and uniquing. Call appropriate interface from
ValueMapper.
llvm-svn: 257389
This patch fixes the memory sanitizer origin store instrumentation for
array types. This can be triggered by cases where frontend lowers
function return to array type instead of aggregation.
For instance, the C code:
--
struct mypair {
int64_t x;
int y;
};
mypair my_make_pair(int64_t x, int y) {
mypair p;
p.x = x;
p.y = y;
return p;
}
int foo (int p)
{
mypair z = my_make_pair(p, 0);
return z.y + z.x;
}
--
It will be lowered with target set to aarch64-linux and -O0 to:
--
[...]
define i32 @_Z3fooi(i32 %p) #0 {
[...]
%call = call [2 x i64] @_Z12my_make_pairxi(i64 %conv, i32 0)
%1 = bitcast %struct.mypair* %z to [2 x i64]*
store [2 x i64] %call, [2 x i64]* %1, align 8
[...]
--
The origin store will emit a 'icmp' to test each store value again the
TLS origin array. However since 'icmp' does not support ArrayType the
memory instrumentation phase will bail out with an error.
This patch change it by using the same strategy used for struct type on
array.
It fixes the 'test/msan/insertvalue_origin.cc' for aarch64 (the -O0 case).
llvm-svn: 257375
JumpThreading's runOnFunction is supposed to return true if it made any
changes. JumpThreading has a call to removeUnreachableBlocks which may
result in changes to the IR but runOnFunction didn't appropriate account
for this possibility, leading to badness.
While we are here, make sure to call LazyValueInfo::eraseBlock in
removeUnreachableBlocks; JumpThreading preserves LVI.
This fixes PR26096.
llvm-svn: 257279
Summary:
This is a fix of D13718. D13718 was committed but then reverted because of the following bug:
https://llvm.org/bugs/show_bug.cgi?id=25299
This patch fixes the issue shown in the bug.
Reviewers: majnemer, reames
Subscribers: jevinskie, llvm-commits
Differential Revision: http://reviews.llvm.org/D14308
llvm-svn: 257277
Summary:
This is analogous to r256079, which removed an overly strong assertion, and
r256812, which simplified the code by replacing three conditionals by one.
Reviewers: reames
Subscribers: sanjoy, llvm-commits
Differential Revision: http://reviews.llvm.org/D16019
llvm-svn: 257250
This patch teaches rewrite-statepoints-for-gc to relocate vector-of-pointers directly rather than trying to split them. This builds on the recent lowering/IR changes to allow vector typed gc.relocates.
The motivation for this is that we recently found a bug in the vector splitting code where depending on visit order, a vector might not be relocated at some safepoint. Specifically, the bug is that the splitting code wasn't updating the side tables (live vector) of other safepoints. As a result, a vector which was live at two safepoints might not be updated at one of them. However, if you happened to visit safepoints in post order over the dominator tree, everything worked correctly. Weirdly, it turns out that post order is actually an incredibly common order to visit instructions in in practice. Frustratingly, I have not managed to write a test case which actually hits this. I can only reproduce it in large IR files produced by actual applications.
Rather than continue to make this code more complicated, we can remove all of the complexity by just representing the relocation of the entire vector natively in the IR.
At the moment, the new functionality is hidden behind a flag. To use this code, you need to pass "-rs4gc-split-vector-values=0". Once I have a chance to stress test with this option and get feedback from other users, my plan is to flip the default and remove the original splitting code. I would just remove it now, but given the rareness of the bug, I figured it was better to leave it in place until the new approach has been stress tested.
Differential Revision: http://reviews.llvm.org/D15982
llvm-svn: 257244
Look for PHI/Select in the same BB of the form
bb:
%p = phi [false, %bb1], [true, %bb2], [false, %bb3], [true, %bb4], ...
%s = select p, trueval, falseval
And expand the select into a branch structure. This later enables
jump-threading over bb in this pass.
Using the similar approach of SimplifyCFG::FoldCondBranchOnPHI(), unfold
select if the associated PHI has at least one constant. If the unfolded
select is not jump-threaded, it will be folded again in the later
optimizations.
llvm-svn: 257198
It's strange that LoopInfo mostly owns the Loop objects, but that it
defers deleting them to the loop pass manager. Instead, change the
oddly named "updateUnloop" to "markAsRemoved" and have it queue the
Loop object for deletion. We can't delete the Loop immediately when we
remove it, since we need its pointer identity still, so we'll mark the
object as "invalid" so that clients can see what's going on.
llvm-svn: 257191
Due to the new in-place ThinLTO symbol handling support added in
r257174, we now invoke renameModuleForThinLTO on the current
module from within the FunctionImport pass.
Additionally, renameModuleForThinLTO no longer needs to return the
Module as it is performing the renaming in place on the one provided.
This commit will be immediately preceeded by a companion clang patch to
remove its invocation of renameModuleForThinLTO.
llvm-svn: 257181
The function importer was still materializing metadata when modules were
loaded for function importing. We only want to materialize it when we
are going to invoke the metadata linking postpass. Materializing it
before function importing is not only unnecessary, but also causes
metadata referenced by imported functions to be mapped in early, and
then not connected to the rest of the module level metadata when it is
ultimately linked in.
Augmented the test case to specifically check for the metadata being
properly connected, which it wasn't before this fix.
llvm-svn: 257171
In setInsertionPoint if the value is not a PHI, Instruction or
Argument it should be a Constant, not a ConstantExpr.
Original commit message:
[InstCombine] Look through PHIs, GEPs, IntToPtrs and PtrToInts to expose more constants when comparing GEPs
Summary:
When comparing two GEP instructions which have the same base pointer
and one of them has a constant index, it is possible to only compare
indices, transforming it to a compare with a constant. This removes
one use for the GEP instruction with the constant index, can reduce
register pressure and can sometimes lead to removing the comparisson
entirely.
InstCombine was already doing this when comparing two GEPs if the base
pointers were the same. However, in the case where we have complex
pointer arithmetic (GEPs applied to GEPs, PHIs of GEPs, conversions to
or from integers, etc) the value of the original base pointer will be
hidden to the optimizer and this transformation will be disabled.
This change detects when the two sides of the comparison can be
expressed as GEPs with the same base pointer, even if they don't
appear as such in the IR. The transformation will convert all the
pointer arithmetic to arithmetic done on indices and all the relevant
uses of GEPs to GEPs with a common base pointer. The GEP comparison
will be converted to a comparison done on indices.
Reviewers: majnemer, jmolloy
Subscribers: hfinkel, jevinskie, jmolloy, aadg, llvm-commits
Differential Revision: http://reviews.llvm.org/D15146
llvm-svn: 257164
a top-down manner into a true top-down or RPO pass over the call graph.
There are specific patterns of function attributes, notably the
norecurse attribute, which are most effectively propagated top-down
because all they us caller information.
Walk in RPO over the call graph SCCs takes the form of a module pass run
immediately after the CGSCC pass managers postorder walk of the SCCs,
trying again to deduce norerucrse for each singular SCC in the call
graph.
This removes a very legacy pass manager specific trick of using a lazy
revisit list traversed during finalization of the CGSCC pass. There is
no analogous finalization step in the new pass manager, and a lazy
revisit list is just trying to produce an RPO iteration of the call
graph. We can do that more directly if more expensively. It seems
unlikely that this will be the expensive part of any compilation though
as we never examine the function bodies here. Even in an LTO run over
a very large module, this should be a reasonable fast set of operations
over a reasonably small working set -- the function call graph itself.
In the future, if this really is a compile time performance issue, we
can look at building support for both post order and RPO traversals
directly into a pass manager that builds and maintains the PO list of
SCCs.
Differential Revision: http://reviews.llvm.org/D15785
llvm-svn: 257163
This remove the need for locking when deleting a function.
Differential Revision: http://reviews.llvm.org/D15988
From: Mehdi Amini <mehdi.amini@apple.com>
llvm-svn: 257139
Limit this transform to a basic block and guard against PHIs.
Hopefully, this fixes the remaining failures in PR25999:
https://llvm.org/bugs/show_bug.cgi?id=25999
llvm-svn: 257133
We marked values which are 'undef' as constant instead of undefined
which violates SCCP's invariants. If we can figure out that a
computation results in 'undef', leave it in the undefined state.
This fixes PR16052.
llvm-svn: 257102
Coverage mapping data may reference names of functions
that are skipped by FE (e.g, unused inline functions). Since
those functions are skipped, normal instr-prof function lowering
pass won't put those names in the right section, so special
handling is needed to walk through coverage mapping structure
and recollect the references.
With this patch, only names that are skipped are processed. This
simplifies the lowering code and it no longer needs to make
assumptions coverage mapping data layout. It should also be
more efficient.
llvm-svn: 257091
The fix for PR23999 made us mark loads of null as producing the constant
undef which upsets the lattice. Instead, keep the load as "undefined".
This fixes PR26044.
llvm-svn: 257087
Summary:
When comparing two GEP instructions which have the same base pointer
and one of them has a constant index, it is possible to only compare
indices, transforming it to a compare with a constant. This removes
one use for the GEP instruction with the constant index, can reduce
register pressure and can sometimes lead to removing the comparisson
entirely.
InstCombine was already doing this when comparing two GEPs if the
base pointers were the same. However, in the case where we have
complex pointer arithmetic (GEPs applied to GEPs, PHIs of GEPs,
conversions to or from integers, etc) the value of the original
base pointer will be hidden to the optimizer and this transformation
will be disabled.
This change detects when the two sides of the comparison can be
expressed as GEPs with the same base pointer, even if they don't
appear as such in the IR. The transformation will convert all the
pointer arithmetic to arithmetic done on indices and all the
relevant uses of GEPs to GEPs with a common base pointer. The
GEP comparison will be converted to a comparison done on indices.
Reviewers: majnemer, jmolloy
Subscribers: hfinkel, jevinskie, jmolloy, aadg, llvm-commits
Differential Revision: http://reviews.llvm.org/D15146
llvm-svn: 257064
At the moment, this is essentially a diangostic option so that I can start collecting failing test cases, but we will eventually migrate to removing the vector splitting code entirely.
llvm-svn: 257015
Summary: This patch adds a check in SplitLandingPadPredecessors to see if the original landingpad instruction has any uses. If not, we don't need to create a PHINode for it in the joint block since it's gonna be a dead code anyway. The motivation for this patch is that we found a bug that SplitLandingPadPredecessors created a PHINode of token type landingpad, which failed the verifier since PHINode can not be token type. However, the created PHINode will never be used in our code pattern. This patch will workaround this bug, and we might add supports in SplitLandingPadPredecessors to handle token type landingpad with uses in the future.
Reviewers: reames
Subscribers: llvm-commits
Differential Revision: http://reviews.llvm.org/D15835
llvm-svn: 256972
Summary: As per title. This will allow the optimizer to pick up on it.
Reviewers: craig.topper, spatel, dexonsmith, Prazek, chandlerc, joker.eph, majnemer
Subscribers: llvm-commits
Differential Revision: http://reviews.llvm.org/D15923
llvm-svn: 256969
Summary: The example in desc should match with actual option name
Reviewers: jmolloy
Differential Revision: http://reviews.llvm.org/D15800
llvm-svn: 256951
This patch prevents us from unintentionally creating entries in the reductions
map for PHIs that are not actually reductions. This is currently not an issue
since we bail out if we encounter PHIs other than inductions or reductions.
However the behavior could become problematic as we add support for additional
recurrence types.
llvm-svn: 256930
Summary: It turns out that if we don't try to do it at the store location, we can do it before any operation that alias the load, as long as no operation alias the store.
Reviewers: craig.topper, spatel, dexonsmith, Prazek, chandlerc, joker.eph
Subscribers: llvm-commits
Differential Revision: http://reviews.llvm.org/D15903
llvm-svn: 256923
If we replace one call-site with another, be sure to move over any
operand bundles that lingered on the old call-site.
This fixes PR26036.
llvm-svn: 256912
Most of the properties of memset_pattern16 can be now covered by the generic attributes and inferred by InferFunctionAttrs. The only exceptions are:
- We don't yet have a writeonly attribute for the first argument.
- We don't have an attribute for modeling the access size facts encoded in MemoryLocation.cpp.
Differential Revision: http://reviews.llvm.org/D15879
llvm-svn: 256911
Summary:
Most of the tool chain is able to optimize scalar and memcpy like operation effisciently while it isn't that good with aggregates. In order to improve the support of aggregate, we try to change aggregate manipulation into either scalar or memcpy like ones whenever possible without loosing informations.
This is one such opportunity.
Reviewers: craig.topper, spatel, dexonsmith, Prazek, chandlerc
Subscribers: llvm-commits
Differential Revision: http://reviews.llvm.org/D15894
llvm-svn: 256868
In r256814, we managed to remove catchpads which were trivially redudant
because they were the same SSA value. We can do better using the same
algorithm but with a smarter datastructure by hashing the SSA values
within the catchpad and comparing them structurally.
llvm-svn: 256815
Summary:
Previously there were three conditionals, checking for global
variables, undef values and everything constant except these two, all three
returning the same value. This commit replaces them by one conditional.
Reviewers: reames
Subscribers: llvm-commits
Differential Revision: http://reviews.llvm.org/D15818
llvm-svn: 256812
Summary:
This commit renames GCRelocateOperands to GCRelocateInst and makes it an
intrinsic wrapper, similar to e.g. MemCpyInst. Also, all users of
GCRelocateOperands were changed to use the new intrinsic wrapper instead.
Reviewers: sanjoy, reames
Subscribers: reames, sanjoy, llvm-commits
Differential Revision: http://reviews.llvm.org/D15762
llvm-svn: 256811
Summary:
At least for CoreCLR, a catchpad which immediately executes an
`unreachable` instruction indicates that the exception can never have a
matching type, and so such catchpads can be removed, and so can their
catchswitches if the catchswitch becomes empty.
Reviewers: rnk, andrew.w.kaylor, majnemer
Subscribers: llvm-commits
Differential Revision: http://reviews.llvm.org/D15846
llvm-svn: 256809
Summary: This patch fixes a bug in prepareICWorklistFromFunction, where the loop becomes infinite with instructions of token type. The patch checks if the instruction is token type, and if so it updates EndInst with the current instruction.
Reviewers: reames, majnemer
Subscribers: llvm-commits, sanjoy
Differential Revision: http://reviews.llvm.org/D15859
llvm-svn: 256792
Update some comments to be more explicit.
Change bypassSlowDivision and the functions it calls so that they take
BasicBlock*s and Instruction*s, rather than Function::iterator&s and
BasicBlock::iterator&s.
Change the APIs so that the caller is responsible for updating the
iterator, rather than the callee. This makes control flow much easier
to follow.
Patch by Justin Lebar!
llvm-svn: 256789
r256763 had promoteLoopAccessesToScalars check for the existence of a
catchswitch when the exit blocks were populated but
promoteLoopAccessesToScalars may be called with a prepopulated set of
exit blocks which would also need to be checked.
This fixes PR26019.
llvm-svn: 256788
This patch removes the isOperatorNewLike predicate since it was only being used to establish a non-null return value and we have attributes specifically for that purpose with generic handling. To keep approximate the same behaviour for existing frontends, I added the various operator new like (i.e. instances of operator new) to InferFunctionAttrs. It's not really clear to me why this isn't handled in Clang, but I didn't want to break existing code and any subtle assumptions it might have.
Once this patch is in, I'm going to start separating the isAllocLike family of predicates. These appear to be being used for a mixture of things which should be more clearly separated and documented. Today, they're being used to indicate (at least) aliasing facts, CSE-ability, and default values from an allocation site.
Differential Revision: http://reviews.llvm.org/D15820
llvm-svn: 256787
This is a resubmission of r256336 which was reverted in r256361. The issue was the lack of the invariant check of the memset value in processLooMemSet().
The original message:
Move several checks into isLegalStores. Also, delineate between those stores that are memset-able and those that are memcpy-able.
llvm-svn: 256783
Before reevaluating instructions, iterate over all instructions
to be reevaluated and remove trivially dead instructions and if
any of it's operands become trivially dead, mark it for deletion
until all trivially dead instructions have been removed
llvm-svn: 256773
We had two bugs here:
- We might try to sink into a catchswitch, causing verifier failures.
- We will succeed in sinking into a cleanuppad but we didn't update the
funclet operand bundle.
This fixes PR26000.
llvm-svn: 256728
This is one last remaining instrumentatation related structure
that needs to be migrate to use the centralized template
definition. With this change, instrumentation code
related to coverage module header will be kept in sync
with the coverage mapping reader. The remaining code
which makes implicit assumption about covmap control
structure layout in the the lowering pass will cleaned
up in a different patch. This patch is not intended to
have no functional change.
llvm-svn: 256715
As suggested in review for r255909, rename MDMaterialized to AllowTemps,
and identify the name of the boolean flag being set in calls to
saveMetadataList.
llvm-svn: 256653
If running the PlaceSafepoints pass on a module which doesn't have the
gc.safepoint_poll function without disabling entry and backedge safepoints,
previously the pass crashed with an obscure error because of a null pointer.
Now it fails the assert instead.
llvm-svn: 256580
The code that was meant to adjust the duplication cost based on the
terminator opcode was not being executed in cases where the initial
threshold was hit inside the loop.
Subscribers: mcrosier, llvm-commits
Differential Revision: http://reviews.llvm.org/D15536
llvm-svn: 256568
InlineCostAnalysis is an analysis pass without any need for it to be one.
Once it stops being an analysis pass, it doesn't maintain any useful state
and the member functions inside can be made free functions. NFC.
Differential Revision: http://reviews.llvm.org/D15701
llvm-svn: 256521
Summary:
Previously, only the outer (last) bitcast was rematerialized, resulting in a
use of the unrelocated inner (first) bitcast after the statepoint. See the
test case for an example.
Reviewers: igor-laevsky, reames
Subscribers: reames, alex, llvm-commits, sanjoy
Differential Revision: http://reviews.llvm.org/D15789
llvm-svn: 256520
a standalone pass.
There is no call graph or even interesting analysis for this part of
function attributes -- it is literally inferring attributes based on the
target library identification. As such, we can do it using a much
simpler module pass that just walks the declarations. This can also
happen much earlier in the pass pipeline which has benefits for any
number of other passes.
In the process, I've cleaned up one particular aspect of the logic which
was necessary in order to separate the two passes cleanly. It now counts
inferred attributes independently rather than just counting all the
inferred attributes as one, and the counts are more clearly explained.
The two test cases we had for this code path are both ... woefully
inadequate and copies of each other. I've kept the superset test and
updated it. We need more testing here, but I had to pick somewhere to
stop fixing everything broken I saw here.
Differential Revision: http://reviews.llvm.org/D15676
llvm-svn: 256466
is (by default) run much earlier than FuncitonAttrs proper.
This allows forcing optnone or other widely impactful attributes. It is
also a bit simpler as the force attribute behavior needs no specific
iteration order.
I've added the pass into the default module pass pipeline and LTO pass
pipeline which mirrors where function attrs itself was being run.
Differential Revision: http://reviews.llvm.org/D15668
llvm-svn: 256465
Summary: This patch changes gc.statepoint intrinsic's return type to token type instead of i32 type. Using token types could prevent LLVM to merge different gc.statepoint nodes into PHI nodes and cause further problems with gc relocations. The patch also changes the way on how gc.relocate and gc.result look for their corresponding gc.statepoint on unwind path. The current implementation uses the selector value extracted from a { i8*, i32 } landingpad as a hook to find the gc.statepoint, while the patch directly uses a token type landingpad (http://reviews.llvm.org/D15405) to find the gc.statepoint.
Reviewers: sanjoy, JosephTremoulet, pgavlin, igor-laevsky, mjacob
Subscribers: reames, mjacob, sanjoy, llvm-commits
Differential Revision: http://reviews.llvm.org/D15662
llvm-svn: 256443
This is an extension of the shuffle combining from r203229:
http://reviews.llvm.org/rL203229
The idea is to widen a short input vector with undef elements so the
existing shuffle transform for extract/insert can kick in.
The motivation is to finally solve PR2109:
https://llvm.org/bugs/show_bug.cgi?id=2109
For that example, the IR becomes:
%1 = bitcast <2 x i32>* %P to <2 x float>*
%ld1 = load <2 x float>, <2 x float>* %1, align 8
%2 = shufflevector <2 x float> %ld1, <2 x float> undef, <4 x i32> <i32 0, i32 1, i32 undef, i32 undef>
%i2 = shufflevector <4 x float> %A, <4 x float> %2, <4 x i32> <i32 0, i32 1, i32 4, i32 5>
ret <4 x float> %i2
And x86 SSE output improves from:
movq (%rdi), %xmm1 ## xmm1 = mem[0],zero
movdqa %xmm1, %xmm2
shufps $229, %xmm2, %xmm2 ## xmm2 = xmm2[1,1,2,3]
shufps $48, %xmm0, %xmm1 ## xmm1 = xmm1[0,0],xmm0[3,0]
shufps $132, %xmm1, %xmm0 ## xmm0 = xmm0[0,1],xmm1[0,2]
shufps $32, %xmm0, %xmm2 ## xmm2 = xmm2[0,0],xmm0[2,0]
shufps $36, %xmm2, %xmm0 ## xmm0 = xmm0[0,1],xmm2[2,0]
retq
To the almost optimal:
movhpd (%rdi), %xmm0
Note: There's a tension in the existing transform related to generating
arbitrary shufflevector masks. We avoid that in other places in InstCombine
because we're scared that codegen can't handle strange masks, but it looks
like we're ok with producing those here. I purposely chose weird insert/extract
indexes for the regression tests to see the effect in these cases.
For PowerPC+Altivec, AArch64, and X86+SSE/AVX, I think the codegen is equal or
better for these examples.
Differential Revision: http://reviews.llvm.org/D15096
llvm-svn: 256394
Move several checks into isLegalStores. Also, delineate between those stores
that are memset-able and those that are memcpy-able.
http://reviews.llvm.org/D15683
Patch by Haicheng Wu <haicheng@codeaurora.org>!
llvm-svn: 256336
Reasons:
1) The existing form was a form of false generality. None of the implemented GCStrategies use anything other than a type. Its becoming more and more clear we're going to need some type of strong GC pointer in the type system and we shouldn't pretend otherwise at this point.
2) The API was awkward when applied to vectors-of-pointers. The old one could have been made to work, but calling isGCManagedPointer(Ty->getScalarType()) is much cleaner than the Value alternatives.
3) The rewriting implementation effectively assumes the type based predicate as well. We should be consistent.
llvm-svn: 256312
Previously, "%" + name of the value was printed for each derived and base
pointer. This is correct for instructions, but wrong for e.g. globals.
llvm-svn: 256305
This reapplies r256277 with two changes:
- In emitFnAttrCompatCheck, change FuncName's type to std::string to fix
a use-after-free bug.
- Remove an unnecessary install-local target in lib/IR/Makefile.
Original commit message for r252949:
Provide a way to specify inliner's attribute compatibility and merging
rules using table-gen. NFC.
This commit adds new classes CompatRule and MergeRule to Attributes.td,
which are used to generate code to check attribute compatibility and
merge attributes of the caller and callee.
rdar://problem/19836465
llvm-svn: 256304
This reapplies r252990 and r252949. I've added member function getKind
to the Attr classes which returns the enum or string of the attribute.
Original commit message for r252949:
Provide a way to specify inliner's attribute compatibility and merging
rules using table-gen. NFC.
This commit adds new classes CompatRule and MergeRule to Attributes.td,
which are used to generate code to check attribute compatibility and
merge attributes of the caller and callee.
rdar://problem/19836465
llvm-svn: 256277
The code for deleting dead global variables and functions was
duplicated.
This is in preparation for also deleting dead global aliases.
llvm-svn: 256274
This patch removes all weight-related interfaces from BPI and replace
them by probability versions. With this patch, we won't use edge weight
anymore in either IR or MC passes. Edge probabilitiy is a better
representation in terms of CFG update and validation.
Differential revision: http://reviews.llvm.org/D15519
llvm-svn: 256263
Summary:
These were deprecated 11 months ago when a generic
llvm.experimental.gc.result intrinsic, which works for all types, was added.
Reviewers: sanjoy, reames
Subscribers: sanjoy, chenli, llvm-commits
Differential Revision: http://reviews.llvm.org/D15719
llvm-svn: 256262
Summary:
Previously, RS4GC crashed in CreateGCRelocates() because it assumed
that every base is also in the array of live variables, which isn't true if a
live variable has a constant base.
This change fixes the crash by making sure CreateGCRelocates() won't try to
relocate a live variable with a constant base. This would be unnecessary
anyway because anything with a constant base won't move.
Reviewers: reames
Subscribers: llvm-commits, sanjoy
Differential Revision: http://reviews.llvm.org/D15556
llvm-svn: 256252
This uses the same criteria used in CFE's CodeGenPGO to identify hot and cold
callees and uses values of inlinehint-threshold and inlinecold-threshold
respectively as the thresholds for such callees.
Differential Revision: http://reviews.llvm.org/D15245
llvm-svn: 256222
This patch adds an option, -safe-stack-no-tls, for using normal
storage instead of thread-local storage for the unsafe stack pointer.
This can be useful when SafeStack is applied to an operating system
kernel.
http://reviews.llvm.org/D15673
Patch by Michael LeMay.
llvm-svn: 256221
The linker requires that a comdat section must be associated
with a another comdat section that precedes it. This
means the comdat section's name needs to use the profile name
var's name.
Patch tested by Johan Engelen.
llvm-svn: 256220
When targeting COFF, it is required that a comdat section to
have a global obj with the same name as the comdat (except for
comdats with select kind to be associative). This fix makes
sure that the comdat is keyed on the data variable for COFF.
Also improved test coverage for this.
llvm-svn: 256193
`CloneAndPruneIntoFromInst` sometimes RAUW's dead instructions with
`undef` before erasing them (to avoid deleting instructions that still
have uses). This changes the `WeakVH` in `OperandBundleCallSites` to
hold an `undef`, and we need to guard for this situation in eventuality
in `llvm::InlineFunction`.
llvm-svn: 256110
Make personality functions, prefix data, and prologue data hungoff
operands of Function.
This is based on the email thread "[RFC] Clean up the way we store
optional Function data" on llvm-dev.
Thanks to sanjoyd, majnemer, rnk, loladiro, and dexonsmith for feedback!
Includes a fix to scrub value subclass data in dropAllReferences. Does not
use binary literals.
Differential Revision: http://reviews.llvm.org/D13829
llvm-svn: 256095
Make personality functions, prefix data, and prologue data hungoff
operands of Function.
This is based on the email thread "[RFC] Clean up the way we store
optional Function data" on llvm-dev.
Thanks to sanjoyd, majnemer, rnk, loladiro, and dexonsmith for feedback!
Includes a fix to scrub value subclass data in dropAllReferences.
Differential Revision: http://reviews.llvm.org/D13829
llvm-svn: 256093
Make personality functions, prefix data, and prologue data hungoff
operands of Function.
This is based on the email thread "[RFC] Clean up the way we store
optional Function data" on llvm-dev.
Thanks to sanjoyd, majnemer, rnk, loladiro, and dexonsmith for feedback!
Differential Revision: http://reviews.llvm.org/D13829
llvm-svn: 256090
As shown by the included test case, it's reasonable to end up with constant references during base pointer calculation. The code actually handled this case just fine, we only had the assert to help isolate problems under the belief that constant references shouldn't be present in IR generated by managed frontends. This turned out to be wrong on two fronts: 1) Manual Jacobs is working on a language with constant references, and b) we found a case where the optimizer does create them in practice.
llvm-svn: 256079
Summary:
First up is instcombine, where in the dbg.declare -> dbg.value conversion,
the llvm.dbg.value needs to be called on the actual loaded value, rather
than the address (since the whole point of this transformation is to be
able to get rid of the alloca). Further, now that that's cleaned up, we
can remove a hack in the backend, that would add an implicit OP_deref if
the argument to dbg.value was an alloca. This stems from before the
existence of DIExpression and is no longer necessary since the deref can
be expressed explicitly.
Now, in order to make sure that the tests pass with this change, we need to
correct the printing of DEBUG_VALUE comments to take into account the
expression, which wasn't taken into account before.
Unfortunately, for both these changes, there were a number of incorrect
test cases (mostly the wrong number of DW_OP_derefs, but also a couple
where the test itself was broken more badly). aprantl and I have gone
through and adjusted these test case in order to make them pass with
these fixes and in some cases to make sure they're actually testing
what they are meant to test.
Reviewers: aprantl
Subscribers: dsanders
Differential Revision: http://reviews.llvm.org/D14186
llvm-svn: 256077
Summary:
If Candiadte may have a different type from GEP, we should bitcast or
pointer cast it to GEP's type so that the later RAUW doesn't complain.
Added a test in nary-gep.ll
Reviewers: tra, meheff
Subscribers: mcrosier, llvm-commits, jholewinski
Differential Revision: http://reviews.llvm.org/D15618
llvm-svn: 256035
Summary:
Third patch split out from http://reviews.llvm.org/D14752.
Only map in needed DISubroutine metadata (imported or otherwise linked
in functions and other DISubroutine referenced by inlined instructions).
This is supported for ThinLTO, LTO and llvm-link --only-needed, with
associated tests for each one.
Depends on D14838.
Reviewers: dexonsmith, joker.eph
Subscribers: davidxl, llvm-commits, joker.eph
Differential Revision: http://reviews.llvm.org/D14843
llvm-svn: 256003
Inspired by the bug reported in 25846. Whatever we end up doing about that one, the value handle change is a generally good one since it will help catch this type of mistake more quickly.
Patch by: Manuel Jacob
llvm-svn: 255984
This extends the same line of reasoning used in EarlyCSE w/http://reviews.llvm.org/D15352 to the DSE implementation in InstCombine.
Key points:
* We only remove unordered or simple stores.
* The loads producing values consumed by dead stores don't influence whether the store is dead.
Differential Revision: http://reviews.llvm.org/D15354
llvm-svn: 255932
The rules for removing trivially dead stores are a lot less complicated than loads. Since we know the later store post dominates the former and the former dominates the later, unless the former has side effects other than the actual store, we can remove it. One slightly surprising thing is that we can freely remove atomic stores, even if the later one isn't atomic. There's no guarantee the atomic one was every visible.
For the moment, we don't handle DSE of ordered atomic stores. We could extend the same chain of reasoning to them, but the catch is we'd then have to model the ordering effect without a store instruction. Since our fences are a stronger than our operation orderings, simple using a fence isn't an obvious win. This arguable calls for a refinement in our fence specification, but that's (much) later work.
Differential Revision: http://reviews.llvm.org/D15352
llvm-svn: 255914
Summary:
Second patch split out from http://reviews.llvm.org/D14752.
Maps metadata as a post-pass from each module when importing complete,
suturing up final metadata to the temporary metadata left on the
imported instructions.
This entails saving the mapping from bitcode value id to temporary
metadata in the importing pass, and from bitcode value id to final
metadata during the metadata linking postpass.
Depends on D14825.
Reviewers: dexonsmith, joker.eph
Subscribers: davidxl, llvm-commits, joker.eph
Differential Revision: http://reviews.llvm.org/D14838
llvm-svn: 255909
As of r255720, the loop pass manager will DTRT when passes update the
loop info for removed loops, so they no longer need to reach into
LPPassManager APIs to do this kind of transformation. This change very
nearly removes the need for the LPPassManager to even be passed into
loop passes - the only remaining pass that uses the LPM argument is
LoopUnswitch.
llvm-svn: 255797
When considering incoming values as part of a reduction phi, ensure the
incoming value is dominated by said phi.
Failing to ensure this property causes miscompiles.
Fixes PR25787.
Many thanks to Mattias Eriksson for reporting, reducing and analyzing the
problem for me.
Differential Revision: http://reviews.llvm.org/D15580
llvm-svn: 255792
In conditional store merging, we were creating PHIs when we didn't
need to. If the value to be predicated isn't defined in the block
we're predicating, then it doesn't need a PHI at all (because we only
deal with triangles and diamonds, any value not in the predicated BB
must dominate the predicated BB).
This fixes a large code size increase in some benchmarks in a popular embedded benchmark suite.
Now with a fix (and fixed tests) for the conformance issue seen in Chromium.
llvm-svn: 255767
Extend EarlyCSE with an additional style of dead store elimination. If we write back a value just read from that memory location, we can eliminate the store under the assumption that the value hasn't changed.
I'm implementing this mostly because I noticed the omission when looking at the code. It seemed strange to have InstCombine have a peephole which was more powerful than EarlyCSE. :)
Differential Revision: http://reviews.llvm.org/D15397
llvm-svn: 255739
An LTO pass that generates a __cfi_check() function that validates a
call based on a hash of the call-site-known type and the target
pointer.
llvm-svn: 255693
(This is the third attempt to check in this patch, and the first two are r255454
and r255460. The once failed test file reg-usage.ll is now moved to
test/Transform/LoopVectorize/X86 directory with target datalayout and target
triple indicated.)
LoopVectorizationCostModel::calculateRegisterUsage() is used to estimate the
register usage for specific VFs. However, it takes into account many
instructions that won't be vectorized, such as induction variables,
GetElementPtr instruction, etc.. This makes the loop vectorizer too conservative
when choosing VF. In this patch, the induction variables that won't be
vectorized plus GetElementPtr instruction will be added to ValuesToIgnore set
so that their register usage won't be considered any more.
Differential revision: http://reviews.llvm.org/D15177
llvm-svn: 255691
SimplifyCFG allows tail merging with code which terminates in
unreachable which, in turn, makes it possible for an invoke to end up in
a funclet which it was not originally part of.
Using operand bundles on invokes allows us to determine whether or not
an invoke was part of a funclet in the source program.
Furthermore, it allows us to unambiguously answer questions about the
legality of inlining into call sites which the personality may have
trouble with.
Differential Revision: http://reviews.llvm.org/D15517
llvm-svn: 255674
A large number of loop utility functions take a `Pass *` and reach
into it to find out which analyses to preserve. There are a number of
problems with this:
- The APIs have access to pretty well any Pass state they want, so
it's hard to tell what they may or may not do.
- Other APIs have copied these and pass around a `Pass *` even though
they don't even use it. Some of these just hand a nullptr to the API
since the callers don't even have a pass available.
- Passes in the new pass manager don't work like the current ones, so
the APIs can't be used as is there.
Instead, we should explicitly thread the analysis results that we
actually care about through these APIs. This is both simpler and more
reusable.
llvm-svn: 255669
This is the last general step to allow more IR-level speculation with a safety harness in place in CodeGenPrepare.
The intent is to restore the behavior enabled by:
http://reviews.llvm.org/rL228826
but prevent bad performance such as:
https://llvm.org/bugs/show_bug.cgi?id=24818
Earlier patches in this sequence:
D12882 (disable SimplifyCFG speculation for expensive instructions)
D13297 (have CGP despeculate expensive ops)
D14630 (have CGP despeculate special versions of cttz/ctlz)
As shown in the test cases, we only have two instructions currently affected: ctz for some x86 and fdiv generally.
Allowing exactly one expensive instruction is a bit of a hack, but it lines up with what is currently implemented
in CGP. If we make the despeculation more general in CGP, we can make the speculation here more liberal.
A follow-up patch will adjust the cost for sqrt and possibly other typically expensive math intrinsics (currently
everything is cheap by default). GPU targets would likely want to override those expensive default costs (just as
they probably should already override the cost of div/rem) because just about any math is cheaper than control-flow
on those targets.
Differential Revision: http://reviews.llvm.org/D15213
llvm-svn: 255660
This patch does two things:
1. mem2reg is now run immediately after globalopt. Now that globalopt
can localize variables more aggressively, it makes sense to lower
them to SSA form earlier rather than later so they can benefit from
the full set of optimization passes.
2. More scalar optimizations are run after the loop optimizations in
LTO mode. The loop optimizations (especially indvars) can clean up
scalar code sufficiently to make it worthwhile running more scalar
passes. I've particularly added SCCP here as it isn't run anywhere
else in the LTO pass pipeline.
Mem2reg is super cheap and shouldn't affect compilation time at all. The
rest of the added passes are in the LTO pipeline only so doesn't affect
the vast majority of compilations, just the link step.
llvm-svn: 255634
For non padded structs, we can just proceed and deaggregate them.
We don't want ot do this when there is padding in the struct as to not
lose information about this padding (the subsequents passes would then
try hard to preserve the padding, which is undesirable).
Also update extractvalue.ll and cast.ll so that they use structs with padding.
Remove the FIXME in the extractvalue of laod case as the non padded case is
handled when processing the load, and we don't want to do it on the padded
case.
Patch by: Amaury SECHET <deadalnix@gmail.com>
Differential Revision: http://reviews.llvm.org/D14483
From: Mehdi Amini <mehdi.amini@apple.com>
llvm-svn: 255600
This moves the actual work to do loop rotation into standalone
functions with the analysis results they need passed in as arguments,
leaving the class itself as a relatively simple shim. This will make
the functions easy to reuse when we're ready to port this
transformation to the new pass manager.
llvm-svn: 255574
This just moves some callers after their callees. My next patch will
convert some of these methods to stand alone functions, and that diff
is more obviously NFC if I move these first. That change, in turn,
will make it much easier to port this pass to the new pass manager
once the loop pass manager is in place.
llvm-svn: 255573
This patch converts code that has access to a LLVMContext to not take a
diagnostic handler.
This has a few advantages
* It is easier to use a consistent diagnostic handler in a single program.
* Less clutter since we are not passing a handler around.
It does make it a bit awkward to implement some C APIs that return a
diagnostic string. I will propose new versions of these APIs and
deprecate the current ones.
llvm-svn: 255571
It turns out that terminatepad gives little benefit over a cleanuppad
which calls the termination function. This is not sufficient to
implement fully generic filters but MSVC doesn't support them which
makes terminatepad a little over-designed.
Depends on D15478.
Differential Revision: http://reviews.llvm.org/D15479
llvm-svn: 255522
This patch add support for variadic argument for AArch64. All the MSAN
unit tests are not passing as well the signal_stress_test (currently
set as XFAIl for aarch64).
llvm-svn: 255495
In conditional store merging, we were creating PHIs when we didn't
need to. If the value to be predicated isn't defined in the block
we're predicating, then it doesn't need a PHI at all (because we only
deal with triangles and diamonds, any value not in the predicated BB
must dominate the predicated BB).
This fixes a large code size increase in some benchmarks in a popular embedded benchmark suite.
llvm-svn: 255489
(This is the second attempt to check in this patch: REQUIRES: asserts is added
to reg-usage.ll now.)
LoopVectorizationCostModel::calculateRegisterUsage() is used to estimate the
register usage for specific VFs. However, it takes into account many
instructions that won't be vectorized, such as induction variables,
GetElementPtr instruction, etc.. This makes the loop vectorizer too conservative
when choosing VF. In this patch, the induction variables that won't be
vectorized plus GetElementPtr instruction will be added to ValuesToIgnore set
so that their register usage won't be considered any more.
Differential revision: http://reviews.llvm.org/D15177
llvm-svn: 255460
LoopVectorizationCostModel::calculateRegisterUsage() is used to estimate the
register usage for specific VFs. However, it takes into account many
instructions that won't be vectorized, such as induction variables,
GetElementPtr instruction, etc.. This makes the loop vectorizer too conservative
when choosing VF. In this patch, the induction variables that won't be
vectorized plus GetElementPtr instruction will be added to ValuesToIgnore set
so that their register usage won't be considered any more.
Differential revision: http://reviews.llvm.org/D15177
llvm-svn: 255454
Before the patch, -fprofile-instr-generate compile will fail
if no integrated-as is specified when the file contains
any static functions (the -S output is also invalid).
This is the second try. The fix in this patch is very localized.
Only profile symbol names of profile symbols with internal
linkage are fixed up while initializer of name syms are not
changes. This means there is no format change nor version bump.
llvm-svn: 255434
This change was discussed in D15392. It allows us to remove the fold that was added
in:
http://reviews.llvm.org/r255261
...and it will allow us to generalize this fold:
http://reviews.llvm.org/rL112232
while preserving the order of bitcast + extract that it produces and testing shows
is better handled by the backend.
Note that the existing check for "isVectorTy()" wasn't strong enough in general
and specifically because: x86_mmx. It's not a vector, but it's not vectorizable
either. So here we check VectorType::isValidElementType() directly before
proceeding with the transform.
llvm-svn: 255433
While we have successfully implemented a funclet-oriented EH scheme on
top of LLVM IR, our scheme has some notable deficiencies:
- catchendpad and cleanupendpad are necessary in the current design
but they are difficult to explain to others, even to seasoned LLVM
experts.
- catchendpad and cleanupendpad are optimization barriers. They cannot
be split and force all potentially throwing call-sites to be invokes.
This has a noticable effect on the quality of our code generation.
- catchpad, while similar in some aspects to invoke, is fairly awkward.
It is unsplittable, starts a funclet, and has control flow to other
funclets.
- The nesting relationship between funclets is currently a property of
control flow edges. Because of this, we are forced to carefully
analyze the flow graph to see if there might potentially exist illegal
nesting among funclets. While we have logic to clone funclets when
they are illegally nested, it would be nicer if we had a
representation which forbade them upfront.
Let's clean this up a bit by doing the following:
- Instead, make catchpad more like cleanuppad and landingpad: no control
flow, just a bunch of simple operands; catchpad would be splittable.
- Introduce catchswitch, a control flow instruction designed to model
the constraints of funclet oriented EH.
- Make funclet scoping explicit by having funclet instructions consume
the token produced by the funclet which contains them.
- Remove catchendpad and cleanupendpad. Their presence can be inferred
implicitly using coloring information.
N.B. The state numbering code for the CLR has been updated but the
veracity of it's output cannot be spoken for. An expert should take a
look to make sure the results are reasonable.
Reviewers: rnk, JosephTremoulet, andrew.w.kaylor
Differential Revision: http://reviews.llvm.org/D15139
llvm-svn: 255422
DenseMap is the wrong data structure to use for sample records and call
sites. The keys are too large, causing massive core memory growth when
reading profiles.
Before this patch, a 21Mb input profile was causing the compiler to grow
to 3Gb in memory. By switching to std::map, the compiler now grows to
300Mb in memory.
There still are some opportunities for memory footprint reduction. I'll
be looking at those next.
llvm-svn: 255389
Revert "[DSE] Disable non-local DSE to see if the bots go green."
Revert "[DeadStoreElimination] Use range-based loops. NFC."
Revert "[DeadStoreElimination] Add support for non-local DSE."
llvm-svn: 255354
GlobalsAA's assumptions that passes do not escape globals not previously
escaped is not violated by AlignmentFromAssumptions and SLPVectorizer. Marking
them as such allows GlobalsAA to be preserved until GVN in the LTO pipeline.
http://lists.llvm.org/pipermail/llvm-dev/2015-December/092972.html
Patch by Vaivaswatha Nagaraj!
llvm-svn: 255348
Mem2Reg shouldn't be optimizing a function that is marked
optnone. There is a test checking this that fails when mem2reg is
explicitly added to the standard pass pipeline.
llvm-svn: 255336
MatchBSwap has most of the functionality to match bit reversals already. If we switch it from looking at bytes to individual bits and remove a few early exits, we can extend the main recursive function to match any sequence of ORs, ANDs and shifts that assemble a value from different parts of another, base value. Once we have this bit->bit mapping, we can very simply detect if it is appropriate for a bswap or bitreverse.
llvm-svn: 255334
This is a redo of r255137 (reverted at r255227) which was a redo of
r255124 (reverted at r255126) with a fixed check for a scalar source
type and an added test for the failure that caused the revert.
Original commit message:
Example:
bitcast (extractelement (bitcast <2 x float> %X to <2 x i32>), 1) to float
--->
extractelement <2 x float> %X, i32 1
This is part of fixing PR25543:
https://llvm.org/bugs/show_bug.cgi?id=25543
The next step will be to generalize this fold:
trunc ( lshr ( bitcast X) ) -> extractelement (X)
Ie, I'm hoping to replace the existing transform of:
bitcast ( trunc ( lshr ( bitcast X)))
added by:
http://reviews.llvm.org/rL112232
with 2 less specific transforms to catch the case in the bug report.
Differential Revision: http://reviews.llvm.org/D14879
llvm-svn: 255261
Added some missing spaces between the module identifier and the start of
the debug message. Also added a ":" after the module identifier to make
this look a little nicer.
llvm-svn: 255259
We extend the search for redundant stores to predecessor blocks that
unconditionally lead to the block BB with the current store instruction. That
also includes single-block loops that unconditionally lead to BB, and
if-then-else blocks where then- and else-blocks unconditionally lead to BB.
http://reviews.llvm.org/D13363
Patch by Ivan Baev <ibaev@codeaurora.org>!
llvm-svn: 255247
Summary:
LAA uses the PredicatedScalarEvolution interface, so it can produce
forward/backward dependences having SCEVs that are AddRecExprs only after being
transformed by PredicatedScalarEvolution.
Use PredicatedScalarEvolution to get the expected expressions.
Reviewers: anemet
Subscribers: llvm-commits, sanjoy
Differential Revision: http://reviews.llvm.org/D15382
llvm-svn: 255241
- This simplifies the CallSite class, arg_begin / arg_end are now
simple wrapper getters.
- In several places, we were creating CallSite instances solely to call
arg_begin and arg_end. With this change, that's no longer required.
llvm-svn: 255226
`CloneAndPruneIntoFromInst` can DCE instructions after cloning them into
the new function, and so an AssertingVH is too strong. This change
switches CloneCodeInfo to use a std::vector<WeakVH>.
llvm-svn: 255148
This is a redo of r255124 (reverted at r255126) with an added check for a
scalar destination type and an added test for the failure seen in Clang's
test/CodeGen/vector.c. The extra test shows a different missing optimization.
Original commit message:
Example:
bitcast (extractelement (bitcast <2 x float> %X to <2 x i32>), 1) to float
--->
extractelement <2 x float> %X, i32 1
This is part of fixing PR25543:
https://llvm.org/bugs/show_bug.cgi?id=25543
The next step will be to generalize this fold:
trunc ( lshr ( bitcast X) ) -> extractelement (X)
Ie, I'm hoping to replace the existing transform of:
bitcast ( trunc ( lshr ( bitcast X)))
added by:
http://reviews.llvm.org/rL112232
with 2 less specific transforms to catch the case in the bug report.
Differential Revision: http://reviews.llvm.org/D14879
llvm-svn: 255137
The bug in IndVarSimplify was fixed in r254976, r254977, so I'm
reapplying the original patch for avoiding redundant LCSSA recomputation.
This reverts commit ffe3b434e505e403146aff00be0c177bb6d13466.
llvm-svn: 255133
This new patch fixes a few bugs that exposed in last submit. It also improves
the test cases.
--Original Commit Message--
This patch implements a minimum spanning tree (MST) based instrumentation for
PGO. The use of MST guarantees minimum number of CFG edges getting
instrumented. An addition optimization is to instrument the less executed
edges to further reduce the instrumentation overhead. The patch contains both the
instrumentation and the use of the profile to set the branch weights.
Differential Revision: http://reviews.llvm.org/D12781
llvm-svn: 255132
Example:
bitcast (extractelement (bitcast <2 x float> %X to <2 x i32>), 1) to float
--->
extractelement <2 x float> %X, i32 1
This is part of fixing PR25543:
https://llvm.org/bugs/show_bug.cgi?id=25543
The next step will be to generalize this fold:
trunc ( lshr ( bitcast X) ) -> extractelement (X)
Ie, I'm hoping to replace the existing transform of:
bitcast ( trunc ( lshr ( bitcast X)))
added by:
http://reviews.llvm.org/rL112232
with 2 less specific transforms to catch the case in the bug report.
Differential Revision: http://reviews.llvm.org/D14879
llvm-svn: 255124
ScalarEvolution.h, in order to avoid cyclic dependencies between the Transform
and Analysis modules:
[LV][LAA] Add a layer over SCEV to apply run-time checked knowledge on SCEV expressions
Summary:
This change creates a layer over ScalarEvolution for LAA and LV, and centralizes the
usage of SCEV predicates. The SCEVPredicatedLayer takes the statically deduced knowledge
by ScalarEvolution and applies the knowledge from the SCEV predicates. The end goal is
that both LAA and LV should use this interface everywhere.
This also solves a problem involving the result of SCEV expression rewritting when
the predicate changes. Suppose we have the expression (sext {a,+,b}) and two predicates
P1: {a,+,b} has nsw
P2: b = 1.
Applying P1 and then P2 gives us {a,+,1}, while applying P2 and the P1 gives us
sext({a,+,1}) (the AddRec expression was changed by P2 so P1 no longer applies).
The SCEVPredicatedLayer maintains the order of transformations by feeding back
the results of previous transformations into new transformations, and therefore
avoiding this issue.
The SCEVPredicatedLayer maintains a cache to remember the results of previous
SCEV rewritting results. This also has the benefit of reducing the overall number
of expression rewrites.
Reviewers: mzolotukhin, anemet
Subscribers: jmolloy, sanjoy, llvm-commits
Differential Revision: http://reviews.llvm.org/D14296
llvm-svn: 255122
Summary:
This change creates a layer over ScalarEvolution for LAA and LV, and centralizes the
usage of SCEV predicates. The SCEVPredicatedLayer takes the statically deduced knowledge
by ScalarEvolution and applies the knowledge from the SCEV predicates. The end goal is
that both LAA and LV should use this interface everywhere.
This also solves a problem involving the result of SCEV expression rewritting when
the predicate changes. Suppose we have the expression (sext {a,+,b}) and two predicates
P1: {a,+,b} has nsw
P2: b = 1.
Applying P1 and then P2 gives us {a,+,1}, while applying P2 and the P1 gives us
sext({a,+,1}) (the AddRec expression was changed by P2 so P1 no longer applies).
The SCEVPredicatedLayer maintains the order of transformations by feeding back
the results of previous transformations into new transformations, and therefore
avoiding this issue.
The SCEVPredicatedLayer maintains a cache to remember the results of previous
SCEV rewritting results. This also has the benefit of reducing the overall number
of expression rewrites.
Reviewers: mzolotukhin, anemet
Subscribers: jmolloy, sanjoy, llvm-commits
Differential Revision: http://reviews.llvm.org/D14296
llvm-svn: 255115
loading the source Module, linking the function in the destination
module, and destroying the source Module before repeating with the
next function to import (potentially from the same Module).
Ideally we would keep the source Module alive and import the next
Function needed from this Module. Unfortunately this is not possible
because the linker does not leave it in a usable state.
However we can do better by first computing the list of all candidates
per Module, and only then load the source Module and import all the
function we need for it.
The trick to process callees is to materialize function in the source
module when building the list of function to import, and inspect them
in their source module, collecting the list of callees for each
callee.
When we move the the actual import, we will import from each source
module exactly once. Each source module is loaded exactly once.
The only drawback it that it requires to have all the lazy-loaded
source Module in memory at the same time.
Currently this patch already improves considerably the link time,
a multithreaded link of llvm-dis on my laptop was:
real 1m12.175s user 6m32.430s sys 0m10.529s
and is now:
real 0m40.697s user 2m10.237s sys 0m4.375s
Note: this is the full link time (linker+Import+Optimizer+CodeGen)
Differential Revision: http://reviews.llvm.org/D15178
From: Mehdi Amini <mehdi.amini@apple.com>
llvm-svn: 255100
For an invoke with operand bundles, the [op_begin(), op_end()-3] range
can contain things other than invoke arguments. This change teaches
PruneEH to use arg_begin() and arg_end() explicitly.
llvm-svn: 255073
This patch teaches the fully redundant load part of EarlyCSE how to forward from atomic and volatile loads and stores, and how to eliminate unordered atomics (only). This patch does not include dead store elimination support for unordered atomics, that will follow in the near future.
The basic idea is that we allow all loads and stores to be tracked by the AvailableLoad table. We store a bit in the table which tracks whether load/store was atomic, and then only replace atomic loads with ones which were also atomic.
No attempt is made to refine our handling of ordered loads or stores. Those are still treated as full fences. We could pretty easily extend the release fence handling to release stores, but that should be a separate patch.
Differential Revision: http://reviews.llvm.org/D15337
llvm-svn: 255054
The StringRef constructor is unnecessary (since we're converting to
std::string anyway), and having it requires an explicit call to
StringRef's or std::string's constructor.
llvm-svn: 255000
Summary:
Also add a stricter post-condition for IndVarSimplify.
Fixes PR25578. Test case by Michael Zolotukhin.
Reviewers: hfinkel, atrick, mzolotukhin
Subscribers: llvm-commits
Differential Revision: http://reviews.llvm.org/D15059
llvm-svn: 254977
254950 ended up being not NFC. The previous code was overriding the flags for whether an instruction read or wrote memory using the target specific flags returned via TTI. I'd missed this in my refactoring. Since I mistakenly built only x86 and didn't notice the number of unsupported tests, I didn't catch that before the original checkin.
This raises an interesting issue though. Given we have function attributes (i.e. readonly, readnone, argmemonly) which describe the aliasing of intrinsics, why does TTI have this information overriding the instruction definition at all? I see no reason for this, but decided to preserve existing behavior for the moment. The root issue might be that we don't have a "writeonly" attribute.
Original commit message:
[EarlyCSE] Simplify and invert ParseMemoryInst [NFCI]
Restructure ParseMemoryInst - which was introduced to abstract over target specific load and stores instructions - to just query the underlying instructions. In theory, this could be slightly slower than caching the results, but in practice, it's very unlikely to be measurable.
The simple query scheme makes it far easier to understand, and much easier to extend with new queries. Given I'm about to need to add new query types, doing the cleanup first seemed worthwhile.
Do we still believe the target specific intrinsic handling is worthwhile in EarlyCSE? It adds quite a bit of complexity and makes the code harder to read. Being able to delete the abstraction entirely would be wonderful.
llvm-svn: 254957
Restructure ParseMemoryInst - which was introduced to abstract over target specific load and stores instructions - to just query the underlying instructions. In theory, this could be slightly slower than caching the results, but in practice, it's very unlikely to be measurable.
The simple query scheme makes it far easier to understand, and much easier to extend with new queries. Given I'm about to need to add new query types, doing the cleanup first seemed worthwhile.
Do we still believe the target specific intrinsic handling is worthwhile in EarlyCSE? It adds quite a bit of complexity and makes the code harder to read. Being able to delete the abstraction entirely would be wonderful.
llvm-svn: 254950
Summary:
Add a field on the PassManagerBuilder that clang or gold can use to pass
down a pointer to the function index in memory to use for importing when
the ThinLTO backend is triggered. Add support to supply this to the
function import pass.
Reviewers: joker.eph, dexonsmith
Subscribers: davidxl, llvm-commits, joker.eph
Differential Revision: http://reviews.llvm.org/D15024
llvm-svn: 254926
Summary:
There are `SelectPatternFlavor`s that don't represent min or max idioms,
and we should not be passing those to `getCmpPredicateForMinMax`.
Fixes PR25745.
Reviewers: majnemer
Subscribers: llvm-commits
Differential Revision: http://reviews.llvm.org/D15249
llvm-svn: 254869
Summary: If the same pass manager is used for multiple modules ASAN
complains about GlobalsMD being initialized twice. Fix this by
resetting GlobalsMD in a new doFinalization method to allow this
use case.
Reviewers: kcc
Subscribers: llvm-commits
Differential Revision: http://reviews.llvm.org/D14962
llvm-svn: 254851
When the notion of target specific memory intrinsics was introduced to EarlyCSE, the commit confused the notions of volatile and simple memory access. Since I'm about to start working on this area, cleanup the naming so that patches aren't horribly confusing. Note that the actual implementation was always bailing if the load or store wasn't simple.
Reminder:
- "volatile" - C++ volatile, can't remove any memory operations, but in principal unordered
- "ordered" - imposes ordering constraints on other nearby memory operations
- "atomic" - can't be split or sheared. In LLVM terms, all "ordered" operations are also atomic so the predicate "isAtomic" is often used.
- "simple" - a load which is none of the above. These are normal loads and what most of the optimizer works with.
llvm-svn: 254805
Summary:
In order to avoid calling pow function we generate repeated fmul when n is a
positive or negative whole number.
For each exponent we pre-compute Addition Chains in order to minimize the no.
of fmuls.
Refer: http://wwwhomes.uni-bielefeld.de/achim/addition_chain.html
We pre-compute addition chains for exponents upto 32 (which results in a max of
7 fmuls).
For eg:
4 = 2+2
5 = 2+3
6 = 3+3 and so on
Hence,
pow(x, 4.0) ==> y = fmul x, x
x = fmul y, y
ret x
For negative exponents, we simply compute the reciprocal of the final result.
Note: This transformation is only enabled under fast-math.
Patch by Mandeep Singh Grang <mgrang@codeaurora.org>
Reviewers: weimingz, majnemer, escha, davide, scanon, joerg
Subscribers: probinson, escha, llvm-commits
Differential Revision: http://reviews.llvm.org/D13994
llvm-svn: 254776
For PowerPC64 we cannot just pass SP extracted from @llvm.stackrestore to
_asan_allocas_unpoison due to specific ABI requirements
(http://refspecs.linuxfoundation.org/ELF/ppc64/PPC-elf64abi.html#DYNAM-STACK).
This patch adds the value returned by @llvm.get.dynamic.area.offset to
extracted from @llvm.stackrestore stack pointer, so dynamic allocas unpoisoning
stuff would work correctly on PowerPC64.
Patch by Max Ostapenko.
Differential Revision: http://reviews.llvm.org/D15108
llvm-svn: 254707
time.
The new overloaded function is used when an attribute is added to a
large number of slots of an AttributeSet (for example, to function
parameters). This is much faster than calling AttributeSet::addAttribute
once per slot, because AttributeSet::getImpl (which calls
FoldingSet::FIndNodeOrInsertPos) is called only once per function
instead of once per slot.
With this commit, clang compiles a file which used to take over 22
minutes in just 13 seconds.
rdar://problem/23581000
Differential Revision: http://reviews.llvm.org/D15085
llvm-svn: 254491
For efficiency reason, when importing multiple functions for the same Module,
we can avoid reparsing it every time.
Differential Revision: http://reviews.llvm.org/D15102
From: Mehdi Amini <mehdi.amini@apple.com>
llvm-svn: 254486
When linking static archive, there is no individual module files to
load. Instead they can be mmap'ed and could be initialized from a
buffer directly. The callback provide flexibility to override the
scheme for loading module from the summary.
Differential Revision: http://reviews.llvm.org/D15101
From: Mehdi Amini <mehdi.amini@apple.com>
llvm-svn: 254479
The difference is that now we don't error on out-of-comdat access to
internal global values. We copy them instead. This seems to match the
expectation of COFF linkers (see pr25686).
Original message:
Start deciding earlier what to link.
A traditional linker is roughly split in symbol resolution and
"copying
stuff".
The two tasks are badly mixed in lib/Linker.
This starts splitting them apart.
With this patch there are no direct call to linkGlobalValueBody or
linkGlobalValueProto. Everything is linked via WapValue.
This also includes a few fixes:
* A GV goes undefined if the comdat is dropped (comdat11.ll).
* We error if an internal GV goes undefined (comdat13.ll).
* We don't link an unused comdat.
The first two match the behavior of an ELF linker. The second one is
equivalent to running globaldce on the input.
llvm-svn: 254418
The current code does not take alloca array size into account and,
as a result, considers any access past the first array element to be
unsafe.
llvm-svn: 254350
A traditional linker is roughly split in symbol resolution and "copying
stuff".
The two tasks are badly mixed in lib/Linker.
This starts splitting them apart.
With this patch there are no direct call to linkGlobalValueBody or
linkGlobalValueProto. Everything is linked via WapValue.
This also includes a few fixes:
* A GV goes undefined if the comdat is dropped (comdat11.ll).
* We error if an internal GV goes undefined (comdat13.ll).
* We don't link an unused comdat.
The first two match the behavior of an ELF linker. The second one is
equivalent to running globaldce on the input.
llvm-svn: 254336
This one is enabled only under -ffast-math. There are cases where the
difference between the value computed and the correct value is huge
even for ffast-math, e.g. as Steven pointed out:
x = -1, y = -4
log(pow(-1), 4) = 0
4*log(-1) = NaN
I checked what GCC does and apparently they do the same optimization
(which result in the dramatic difference). Future work might try to
make this (slightly) less worse.
Differential Revision: http://reviews.llvm.org/D14400
llvm-svn: 254263
This fixes buildbots in systems that std::to_string is not present. It
also tidies the output of the diagnostic to render doubles a bit better
(thanks Ben Kramer for help with string streams and format).
llvm-svn: 254261
This adds two thresholds to the sample profiler to affect inlining
decisions: the concept of global hotness and coldness.
Functions that have accumulated more than a certain fraction of samples at
runtime, are annotated with the InlineHint attribute. Conversely,
functions that accumulate less than a certain fraction of samples, are
annotated with the Cold attribute.
This is very similar to the hints emitted by Clang when using
instrumentation profiles.
Notice that this is a very blunt instrument. A function may have
globally collected a significant fraction of samples, but that does not
necessarily mean that every callsite for that function is hot.
Ideally, we would annotate each callsite with the samples collected at
that callsite. This way, the inliner can incorporate all these weights
into its cost model.
Once the inliner offers this functionality, we can change the hints
emitted here to a more precise per-callsite annotation. For now, this is
providing some measure of speedups with our internal benchmarks. I've
observed speedups of up to 23% (though the geo mean is about 3%). I expect
these numbers to improve as the inliner gets better annotations.
llvm-svn: 254212
Based on testing of internal benchmarks, I'm lowering this threshold to
a value of 0.1%. This means that SamplePGO will respect 99.9% of the
original inline decisions when following a profile.
The performance difference is noticeable in some tests. With the
previous threshold, the speedups over baseline -O2 was about 0.63%. With
the new default, the speedups are around 3% on average.
The point of this threshold is not to do more aggressive inlining. When
an inlined callsite crosses this threshold, SamplePGO will redo the
inline decision so that it can better apply the input profile.
By respecting most original inline decisions, we can apply more of the
input profile because the shape of the code follows the profile more
closely.
In the next series, I'll be looking at adding some inline hints for the
cold callsites and for toplevel functions that are hot/cold as well.
llvm-svn: 254211
Now the ValueMapper has two callbacks. The first one maps the
declaration. The ValueMapper records the mapping and then materializes
the body/initializer.
llvm-svn: 254209
This patch changes the DFSan instrumentation for aarch64 to instead
of using fixes application mask defined by SANITIZER_AARCH64_VMA
to read the application shadow mask value from compiler-rt. The value
is initialized based on runtime VAM detection.
Along with this patch a compiler-rt one will also be added to export
the shadow mask variable.
llvm-svn: 254196
The order in which instructions are truncated in truncateToMinimalBitwidths
effects code generation. Switch to a map with a determinisic order, since the
iteration order over a DenseMap is not defined.
This code is not hot, so the difference in container performance isn't
interesting.
Many thanks to David Blaikie for making me aware of MapVector!
Fixes PR25490.
Differential Revision: http://reviews.llvm.org/D14981
llvm-svn: 254179
They are as much trouble as aliases to declarations. They are requiring
the code generator to define a symbol with the same value as another
symbol, but the second symbol is undefined.
If representing this is important for some optimization, we could add
support for available_externally aliases. They would be *required* to
point to a declaration (or available_externally definition).
llvm-svn: 254170
Add a simple initial heuristic to control importing based on the number
of instructions recorded in the function's summary. Add option to
control the limit, and test using option.
llvm-svn: 254036
When the original binary is executed and sampled, the resulting profile
contains information on the original inline stack. We currently follow
the original inline plan if we notice that the inlined callsite has more
than 0 samples to it.
A better way is to determine whether the callsite is actually worth
inlining. If the callsite accumulates a small fraction of the samples
spent in the parent function, then we don't want to bother inlining it
(as it means that the callsite is actually cold).
This patch introduces a threshold expressed in percentage of samples
in relation to the parent function. If the callsite uses less than N%
of the total samples used by its parent, the original inline decision is
not re-applied.
I've set the threshold to the very arbitrary value of 5%. I'm yet to do
any actual experiments to see what's a good value. I wanted to separate
the basic mechanism from the tuning.
llvm-svn: 254034
This patch implements a minimum spanning tree (MST) based instrumentation for
PGO. The use of MST guarantees minimum number of CFG edges getting
instrumented. An addition optimization is to instrument the less executed
edges to further reduce the instrumentation overhead. The patch contains both the
instrumentation and the use of the profile to set the branch weights.
Differential Revision: http://reviews.llvm.org/D12781
llvm-svn: 254021
Analyze imported function bodies and add any new external calls to
the worklist for importing. Currently no controls on the importing
so this will end up importing everything possible in the call tree
below the importing module. Basic profitability checks coming next.
Update test to check for iteratively inlined functions.
llvm-svn: 254011
Summary:
Followed the guidelines in:
http://llvm.org/docs/CodingStandards.html#include-style
However, I noticed that uppercase named headers come before lowercase ones
throughout the codebase. So kept them as is.
Patch by Mandeep Singh Grang <mgrang@codeaurora.org>
Reviewers: majnemer, davide, jmolloy, atrick
Subscribers: sanjoy
Differential Revision: http://reviews.llvm.org/D14939
llvm-svn: 254005
Daniel Berlin