Commit Graph

8410 Commits

Author SHA1 Message Date
Nick Lewycky
4a3935c27e A dead malloc, a free(NULL) and a free(undef) are all trivially dead
instructions.

This doesn't introduce any optimizations we weren't doing before (except
potentially due to pass ordering issues), now passes will eliminate them sooner
as part of their own cleanups.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@142787 91177308-0d34-0410-b5e6-96231b3b80d8
2011-10-24 04:35:36 +00:00
Cameron Zwarich
90747e34e6 The element insertion code in scalar replacement doesn't handle incorrect
element types, even though the element extraction code does. It is surprising
that this bug has been here for so long. Fixes <rdar://problem/10318778>.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@142740 91177308-0d34-0410-b5e6-96231b3b80d8
2011-10-23 07:02:10 +00:00
Nick Lewycky
4d882aae2a A non-escaping malloc in the entry block is not unlike an alloca. Do dead-store
elimination on them too.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@142735 91177308-0d34-0410-b5e6-96231b3b80d8
2011-10-22 21:59:35 +00:00
Eli Friedman
4090e1ce91 Remap blockaddress correctly when inlining a function. Fixes PR10162.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@142684 91177308-0d34-0410-b5e6-96231b3b80d8
2011-10-21 20:45:19 +00:00
Eli Friedman
8d992f5c2c Minor simplification: use ShuffleVectorInst::getMaskValue instead of a more expensive helper.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@142672 91177308-0d34-0410-b5e6-96231b3b80d8
2011-10-21 19:11:34 +00:00
Eli Friedman
d2822e7572 Extend instcombine's shufflevector simplification to handle more cases where the input and output vectors have different sizes. Patch by Xiaoyi Guo.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@142671 91177308-0d34-0410-b5e6-96231b3b80d8
2011-10-21 19:06:29 +00:00
Eli Friedman
c66330504c Refactor code from inlining and globalopt that checks whether a function definition is unused, and enhance it so it can tell that functions which are only used by a blockaddress are in fact dead. This probably doesn't happen much on most code, but the Linux kernel's _THIS_IP_ can trigger this issue with blockaddress. (GlobalDCE can also handle the given tescase, but we only run that at -O3.) Found while looking at PR11180.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@142572 91177308-0d34-0410-b5e6-96231b3b80d8
2011-10-20 05:23:42 +00:00
Devang Patel
9be72d4394 Initialze ScalarEvalution dependency.
Patch by Pranav Bhandarkar!


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@142556 91177308-0d34-0410-b5e6-96231b3b80d8
2011-10-19 23:56:07 +00:00
Dan Gohman
a974beaa1f Teach the ARC optimizer about the !clang.arc.copy_on_escape metadata
tag on objc_retainBlock calls, which indicates that they may be
optimized away. rdar://10211286.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@142298 91177308-0d34-0410-b5e6-96231b3b80d8
2011-10-17 22:53:25 +00:00
Bill Wendling
76f267df17 Add support for the Objective-C personality function to the instruction
combining of the landingpad instruction. The ObjC personality function acts
almost identically to the C++ personality function. In particular, it uses
"null" as a "catch-all" value.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@142256 91177308-0d34-0410-b5e6-96231b3b80d8
2011-10-17 21:20:24 +00:00
Dan Gohman
90b8bcd33a Suppress partial retain+release elimination when there's a
possibility that it will span multiple CFG diamonds/triangles which
could have different controlling predicates.  rdar://10282956


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@142222 91177308-0d34-0410-b5e6-96231b3b80d8
2011-10-17 18:48:25 +00:00
Bill Wendling
3c5e60994f Correct over-zealous removal of hack.
Some code want to check that *any* call within a function has the 'returns
twice' attribute, not just that the current function has one.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@142221 91177308-0d34-0410-b5e6-96231b3b80d8
2011-10-17 18:43:40 +00:00
Bill Wendling
728662f9e8 Now that we have the ReturnsTwice function attribute, this method is
obsolete. Check the attribute instead.
<rdar://problem/8031714>


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@142212 91177308-0d34-0410-b5e6-96231b3b80d8
2011-10-17 18:22:52 +00:00
Michael J. Spencer
9904056a70 Fix CMake build.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@142204 91177308-0d34-0410-b5e6-96231b3b80d8
2011-10-17 17:50:39 +00:00
Devang Patel
827454e6e2 svn mv Target/ARM/ARMGlobalMerge.cpp Transforms/Scalar/GlobalMerge.cpp
There is no reason to have simple IR level pass in lib/Target.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@142200 91177308-0d34-0410-b5e6-96231b3b80d8
2011-10-17 17:17:43 +00:00
Chandler Carruth
602650c988 Add a routine to swap branch instruction operands, and update any
profile metadata at the same time. Use it to preserve metadata attached
to a branch when re-writing it in InstCombine.

Add metadata to the canonicalize_branch InstCombine test, and check that
it is tranformed correctly.

Reviewed by Nick Lewycky!

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@142168 91177308-0d34-0410-b5e6-96231b3b80d8
2011-10-17 01:11:57 +00:00
Chandler Carruth
5820d62803 Add a proper LLVM banner to this file.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@142162 91177308-0d34-0410-b5e6-96231b3b80d8
2011-10-16 22:15:07 +00:00
Nick Lewycky
36c7e6c36c When looking for dependencies on the src pointer, scan the src pointer. Scanning
on the memcpy call will pull up other unrelated stuff. Fixes PR11142.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@142150 91177308-0d34-0410-b5e6-96231b3b80d8
2011-10-16 20:13:32 +00:00
Duncan Sands
1673b15da2 Don't replace all dominated uses if there is only one use, since that
use can't be dominated, saving one domtree lookup.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@142066 91177308-0d34-0410-b5e6-96231b3b80d8
2011-10-15 11:13:42 +00:00
Andrew Trick
513b1f47c1 Fix indvars randomness by removing iteration over a map.
I rewrote the algorithm a while back so it doesn't require map lookup,
but neglected to change the data structure. This was caught by
llvm-gcc self host, not because there's anything special about
llvm-gcc, but because it is the only test for nondeterminism we
currently have. Unit tests don't work well for everything; we should
always try to have a nondeterminism stress test running.

Fixes PR11133: llvm-gcc self host .o mismatch after enable-iv-rewrite=false


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@142036 91177308-0d34-0410-b5e6-96231b3b80d8
2011-10-15 01:38:14 +00:00
Eli Friedman
dae36ba802 Avoid undefined behavior in negation in LSR. Patch by Ahmed Charles.
Someone more familiar with LSR should double-check that the extra cast is actually doing the right thing in the overflow cases; I'm not completely confident that's that case. 



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@141916 91177308-0d34-0410-b5e6-96231b3b80d8
2011-10-13 23:48:33 +00:00
Eli Friedman
b414142036 Enhance the memdep interface so that users can tell the difference between a dependency which cannot be calculated and a path reaching the entry point of the function. This patch introduces isNonFuncLocal, which replaces isUnknown in some cases.
Patch by Xiaoyi Guo.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@141896 91177308-0d34-0410-b5e6-96231b3b80d8
2011-10-13 22:14:57 +00:00
Eli Friedman
18ead6b587 Fix a couple hash functions so that they do not depend on undefined shifts. Based on patch by Ahmed Charles.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@141820 91177308-0d34-0410-b5e6-96231b3b80d8
2011-10-12 22:00:26 +00:00
Nick Lewycky
865703e53a Add missing space.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@141750 91177308-0d34-0410-b5e6-96231b3b80d8
2011-10-12 00:14:31 +00:00
Cameron Zwarich
c055a8782e Fix PR11106 by correcting a typo that has been in the code for over a year. This
would have never worked, since the element type of a vector type is never a
vector type. Also fix the conditional to be more direct in checking whether
EltTy is a vector type.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@141713 91177308-0d34-0410-b5e6-96231b3b80d8
2011-10-11 21:26:40 +00:00
Cameron Zwarich
446d95224b Remove a lot of the fancy scalar replacement code for dealing with llvm-gcc's
lowering of NEON code. It provides little-to-no benefit now and only introduces
additional complexity.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@141646 91177308-0d34-0410-b5e6-96231b3b80d8
2011-10-11 06:10:30 +00:00
Andrew Trick
a02bfced06 Add experimental -enable-lsr-phielim option.
I'm not sure we will need it in the long run, but the option is
currently useful for checking if the output of LSR is "clean".


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@141634 91177308-0d34-0410-b5e6-96231b3b80d8
2011-10-11 02:30:45 +00:00
Andrew Trick
204494149b Move replaceCongruentIVs into SCEVExapander and bias toward "expanded"
IVs.

Indvars previously chose randomly between congruent IVs. Now it will
bias the decision toward IVs that SCEVExpander likes to create. This
was not done to fix any problem, it's just a welcome side effect of
factoring code.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@141633 91177308-0d34-0410-b5e6-96231b3b80d8
2011-10-11 02:28:51 +00:00
Lang Hames
bb5b3f3359 Add a natural stack alignment field to TargetData, and prevent InstCombine from
promoting allocas to preferred alignments that exceed the natural
alignment. This avoids some potentially expensive dynamic stack realignments.

The natural stack alignment is set in target data strings via the "S<size>"
option. Size is in bits and must be a multiple of 8. The natural stack alignment
defaults to "unspecified" (represented by a zero value), and the "unspecified"
value does not prevent any alignment promotions. Target maintainers that care
about avoiding promotions should explicitly add the "S<size>" option to their
target data strings.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@141599 91177308-0d34-0410-b5e6-96231b3b80d8
2011-10-10 23:42:08 +00:00
Andrew Trick
c570191060 LSR should only reuse phis that match its formula.
Fixes rdar://problem/5064068


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@141442 91177308-0d34-0410-b5e6-96231b3b80d8
2011-10-07 23:46:21 +00:00
Duncan Sands
3f329cb781 Teach GVN to also propagate switch cases. For example, in this code
switch (n) {
    case 27:
      do_something(x);
    ...
  }
the call do_something(x) will be replaced with do_something(27).  In
gcc-as-one-big-file this results in the removal of about 500 lines of
bitcode (about 0.02%), so has about 1/10 of the effect of propagating
branch conditions.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@141360 91177308-0d34-0410-b5e6-96231b3b80d8
2011-10-07 08:29:06 +00:00
Eli Friedman
8540101252 Remove the old atomic instrinsics. autoupgrade functionality is included with this patch.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@141333 91177308-0d34-0410-b5e6-96231b3b80d8
2011-10-06 23:20:49 +00:00
Eli Friedman
792860883e PR11061: Make simplifylibcalls fold strcmp("", x) correctly.
While I'm here, fix the related issue with strncmp, add some actual tests for strcmp and strncmp, and start using StringRef::compare for constant folding instead of using strcmp/strncmp so that the optimized IR isn't dependent on the host's implementation of strcmp.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@141227 91177308-0d34-0410-b5e6-96231b3b80d8
2011-10-05 22:27:16 +00:00
Jim Grosbach
35d9da3d3b Re-commit 141203, but much more conservative.
Just pull the instruction name, but don't change the order of anything
else. That keeps --debug happy and non-crashing, but doesn't change
how the worklist gets built.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@141210 91177308-0d34-0410-b5e6-96231b3b80d8
2011-10-05 20:53:43 +00:00
Jim Grosbach
e2999b4899 Revert 141203. InstCombine is looping on unit tests.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@141209 91177308-0d34-0410-b5e6-96231b3b80d8
2011-10-05 20:44:29 +00:00
Jim Grosbach
30c1ff234d Update InstCombine worklist after instruction transform is complete.
When updating the worklist for InstCombine, the Add/AddUsersToWorklist
functions may access the instruction(s) being added, for debug output for
example. If the instructions aren't yet added to the basic block, this
can result in a crash. Finish the instruction transformation before
adjusting the worklist instead.

rdar://10238555


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@141203 91177308-0d34-0410-b5e6-96231b3b80d8
2011-10-05 20:05:00 +00:00
Duncan Sands
02b5e72ac6 GVN does simple propagation of conditions: when it sees a conditional
branch "br i1 %x, label %if_true, label %if_false" then it replaces
"%x" with "true" in places only reachable via the %if_true arm, and
with "false" in places only reachable via the %if_false arm.  Except
that actually it doesn't: if value numbering shows that %y is equal
to %x then, yes, %y will be turned into true/false in this way, but
any occurrences of %x itself are not transformed.  Fix this.  What's
more, it's often the case that %x is an equality comparison such as
"%x = icmp eq %A, 0", in which case every occurrence of %A that is
only reachable via the %if_true arm can be replaced with 0.  Implement
this and a few other variations on this theme.  This reduces the number
of lines of LLVM IR in "GCC as one big file" by 0.2%.  It has a bigger
impact on Ada code, typically reducing the number of lines of bitcode
by around 0.4% by removing repeated compiler generated checks.  Passes
the LLVM nightly testsuite and the Ada ACATS testsuite.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@141177 91177308-0d34-0410-b5e6-96231b3b80d8
2011-10-05 14:28:49 +00:00
Duncan Sands
452c58f4c4 Generalize GVN's conditional propagation logic slightly:
it's OK for the false/true destination to have multiple
predecessors as long as the extra ones are dominated by
the branch destination.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@141176 91177308-0d34-0410-b5e6-96231b3b80d8
2011-10-05 14:17:01 +00:00
Andrew Trick
f143b79b78 LSR should avoid redundant edge splitting.
This handles the case in which LSR rewrites an IV user that is a phi and
splits critical edges originating from a switch.
Fixes <rdar://problem/6453893> LSR is not splitting edges "nicely"


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@141059 91177308-0d34-0410-b5e6-96231b3b80d8
2011-10-04 03:50:44 +00:00
Andrew Trick
2aeb8027d6 whitespace
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@141058 91177308-0d34-0410-b5e6-96231b3b80d8
2011-10-04 03:34:49 +00:00
Nick Lewycky
11357d4f40 Add a new icmp+select optz'n. Also shows off the load(cst) folding added in
r140966.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@140969 91177308-0d34-0410-b5e6-96231b3b80d8
2011-10-02 10:37:37 +00:00
Nick Lewycky
267236ade3 Enhance a couple places where we were doing constant folding of instructions,
but not load instructions. Noticed by inspection.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@140966 91177308-0d34-0410-b5e6-96231b3b80d8
2011-10-02 09:12:55 +00:00
Andrew Trick
b2ab2fa524 Inlining and unrolling heuristics should be aware of free truncs.
We want heuristics to be based on accurate data, but more importantly
we don't want llvm to behave randomly. A benign trunc inserted by an
upstream pass should not cause a wild swings in optimization
level. See PR11034. It's a general problem with threshold-based
heuristics, but we can make it less bad.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@140919 91177308-0d34-0410-b5e6-96231b3b80d8
2011-10-01 01:39:05 +00:00
Andrew Trick
5c655413cf whitespace
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@140916 91177308-0d34-0410-b5e6-96231b3b80d8
2011-10-01 01:27:56 +00:00
Jim Grosbach
68e05fb368 Don't modify constant in-place.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@140875 91177308-0d34-0410-b5e6-96231b3b80d8
2011-09-30 19:58:46 +00:00
Jim Grosbach
cbf676b3ba float comparison to double 'zero' constant can just be a float 'zero.'
InstCombine was incorrectly considering the conversion of the constant
zero to be unsafe.

We want to transform:
define float @bar(float %x) nounwind readnone optsize ssp {
  %conv = fpext float %x to double
  %cmp = fcmp olt double %conv, 0.000000e+00
  %conv1 = zext i1 %cmp to i32
  %conv2 = sitofp i32 %conv1 to float
  ret float %conv2
}

Into:
define float @bar(float %x) nounwind readnone optsize ssp {
  %cmp = fcmp olt float %x, 0.000000e+00   ; <---- This
  %conv1 = zext i1 %cmp to i32
  %conv2 = sitofp i32 %conv1 to float
  ret float %conv2
}


rdar://10215914


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@140869 91177308-0d34-0410-b5e6-96231b3b80d8
2011-09-30 18:45:50 +00:00
Jim Grosbach
0cc4a958f3 Tidy up. Trailing whitespace.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@140865 91177308-0d34-0410-b5e6-96231b3b80d8
2011-09-30 18:09:53 +00:00
Duncan Sands
0ad7b6e773 Inlining often produces landingpad instructions with repeated
catch or repeated filter clauses.  Teach instcombine a bunch
of tricks for simplifying landingpad clauses.  Currently the
code only recognizes the GNU C++ and Ada personality functions,
but that doesn't stop it doing a bunch of "generic" transforms
which are hopefully fine for any real-world personality function.
If these "generic" transforms turn out not to be generic, they
can always be conditioned on the personality function.  Probably
someone should add the ObjC++ personality function.  I didn't as
I don't know anything about it.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@140852 91177308-0d34-0410-b5e6-96231b3b80d8
2011-09-30 13:12:16 +00:00
Nick Lewycky
48105286cb Fold two identical set lookups into one. No functionality change.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@140821 91177308-0d34-0410-b5e6-96231b3b80d8
2011-09-29 23:40:12 +00:00
Dan Gohman
27e0666725 When eliminating unnecessary retain+autorelease on return values,
handle the case where the retain is in a different basic block.
rdar://10210274.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@140815 91177308-0d34-0410-b5e6-96231b3b80d8
2011-09-29 22:27:34 +00:00