Commit Graph

66 Commits

Author SHA1 Message Date
Nick Lewycky 5ef6bc8815 Improve 'tail' call marking in TRE. A bootstrap of clang goes from 375k calls marked tail in the IR to 470k, however this improvement does not carry into an improvement of the call/jmp ratio on x86. The most common pattern is a tail call + br to a block with nothing but a 'ret'.
The number of tail call to loop conversions remains the same (1618 by my count).

The new algorithm does a local scan over the use-def chains to identify local "alloca-derived" values, as well as points where the alloca could escape. Then, a visit over the CFG marks blocks as being before or after the allocas have escaped, and annotates the calls accordingly.

llvm-svn: 208017
2014-05-05 23:59:03 +00:00
Reid Kleckner 9b2cc647eb Fix PR7272 in -tailcallelim instead of the inliner
The -tailcallelim pass should be checking if byval or inalloca args can
be captured before marking calls as tail calls.  This was the real root
cause of PR7272.

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

Reviewers: chandlerc

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

llvm-svn: 206789
2014-04-21 20:48:47 +00:00
Daniel Dunbar 9efbedfd35 [tests] Cleanup initialization of test suffixes.
- Instead of setting the suffixes in a bunch of places, just set one master
   list in the top-level config. We now only modify the suffix list in a few
   suites that have one particular unique suffix (.ml, .mc, .yaml, .td, .py).

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

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

llvm-svn: 188513
2013-08-16 00:37:11 +00:00
Stephen Lin a76289aa1b Catch more CHECK that can be converted to CHECK-LABEL in Transforms for easier debugging. No functionality change.
This conversion was done with the following bash script:

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

llvm-svn: 186269
2013-07-14 01:50:49 +00:00
Stephen Lin c1c7a1309c Update Transforms tests to use CHECK-LABEL for easier debugging. No functionality change.
This update was done with the following bash script:

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

llvm-svn: 186268
2013-07-14 01:42:54 +00:00
Michael Gottesman b40db26eae Teach TailRecursionElimination to handle certain cases of nocapture escaping allocas.
Without the changes introduced into this patch, if TRE saw any allocas at all,
TRE would not perform TRE *or* mark callsites with the tail marker.

Because TRE runs after mem2reg, this inadequacy is not a death sentence. But
given a callsite A without escaping alloca argument, A may not be able to have
the tail marker placed on it due to a separate callsite B having a write-back
parameter passed in via an argument with the nocapture attribute.

Assume that B is the only other callsite besides A and B only has nocapture
escaping alloca arguments (*NOTE* B may have other arguments that are not passed
allocas). In this case not marking A with the tail marker is unnecessarily
conservative since:

  1. By assumption A has no escaping alloca arguments itself so it can not
     access the caller's stack via its arguments.

  2. Since all of B's escaping alloca arguments are passed as parameters with
     the nocapture attribute, we know that B does not stash said escaping
     allocas in a manner that outlives B itself and thus could be accessed
     indirectly by A.

With the changes introduced by this patch:

  1. If we see any escaping allocas passed as a capturing argument, we do
     nothing and bail early.

  2. If we do not see any escaping allocas passed as captured arguments but we
     do see escaping allocas passed as nocapture arguments:

       i. We do not perform TRE to avoid PR962 since the code generator produces
          significantly worse code for the dynamic allocas that would be created
          by the TRE algorithm.

       ii. If we do not return twice, mark call sites without escaping allocas
           with the tail marker. *NOTE* This excludes functions with escaping
           nocapture allocas.

  3. If we do not see any escaping allocas at all (whether captured or not):

       i. If we do not have usage of setjmp, mark all callsites with the tail
          marker.

       ii. If there are no dynamic/variable sized allocas in the function,
           attempt to perform TRE on all callsites in the function.

Based off of a patch by Nick Lewycky.

rdar://14324281.

llvm-svn: 186057
2013-07-11 04:40:01 +00:00
Michael Gottesman 275b22e310 [TRE] Combined another test into basic.ll
llvm-svn: 185729
2013-07-05 22:24:06 +00:00
Michael Gottesman e283e1958a [TRE] Merged several tests into the the test basic.ll.
llvm-svn: 185723
2013-07-05 20:45:13 +00:00
Jan Wen Voung 6dc3076080 Revert the test moves from 176733. Use "REQUIRES: asserts" instead.
llvm-svn: 176873
2013-03-12 16:27:52 +00:00
Jan Wen Voung 7857a64909 Disable statistics on Release builds and move tests that depend on -stats.
Summary:
Statistics are still available in Release+Asserts (any +Asserts builds),
and stats can also be turned on with LLVM_ENABLE_STATS.

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

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

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

llvm-svn: 176733
2013-03-08 22:56:31 +00:00
Michael Gottesman 5284bd013f Converted test dont-tce-tail-marked-call.ll to use FileCheck.
llvm-svn: 172172
2013-01-11 04:16:35 +00:00
Michael Gottesman 93a0d49c7e This commit is a 4x squash commit consisting of 4x functions converted to use FileCheck instead of grep.
Messages:
Converted test case trivial_codegen_tailcall.ll to use FileCheck.
Converted test return_constant.ll to use FileCheck instead of grep.
Converted test reorder_load.ll to use FileCheck instead of grep.
Converted test intervening-inst.ll to use FileCheck instead of grep.

llvm-svn: 172171
2013-01-11 04:12:53 +00:00
Dmitri Gribenko 86fb558d9a Tests: rewrite 'opt ... %s' to 'opt ... < %s' so that opt does not emit a ModuleID
This is done to avoid odd test failures, like the one fixed in r171243.

While there, FileCheck'ize tests.

llvm-svn: 171344
2013-01-01 14:04:36 +00:00
Dmitri Gribenko d7beca87f5 Tests: rewrite 'opt ... %s' to 'opt ... < %s' so that opt does not emit a ModuleID
This is done to avoid odd test failures, like the one fixed in r171243.

My previous regex was not good enough to find these.

llvm-svn: 171343
2013-01-01 13:57:25 +00:00
Dmitri Gribenko b137c9e551 Tests: rewrite 'opt ... %s' to 'opt ... < %s' so that opt does not emit a ModuleID
This is done to avoid odd test failures, like the one fixed in r171243.

llvm-svn: 171246
2012-12-30 01:28:40 +00:00
Argyrios Kyrtzidis 54ff5e81a1 Revert r166407 because it caused analyzer tests to crash and broke self-host bots.
llvm-svn: 166424
2012-10-22 18:16:14 +00:00
Nick Lewycky 8b67e1e0b9 Reapply r166405, teaching tailcallelim to be smarter about nocapture, with a
very small but very important bugfix:
  bool shouldExplore(Use *U) {
    Value *V = U->get();
    if (isa<CallInst>(V) || isa<InvokeInst>(V))
    [...]
should have read:
  bool shouldExplore(Use *U) {
    Value *V = U->getUser();
    if (isa<CallInst>(V) || isa<InvokeInst>(V))
Fixes PR14143!

llvm-svn: 166407
2012-10-22 03:03:52 +00:00
NAKAMURA Takumi 60d56d2eea Revert r166405, "Teach TailRecursionElimination to consider 'nocapture' when deciding whether"
It broke selfhosting stage2 in several builders.

llvm-svn: 166406
2012-10-22 00:48:51 +00:00
Nick Lewycky 2d28f2bf83 Teach TailRecursionElimination to consider 'nocapture' when deciding whether
calls can be marked tail.

llvm-svn: 166405
2012-10-21 23:51:22 +00:00
Chandler Carruth 5da53436d5 Convert the uses of '|&' to use '2>&1 |' instead, which works on old
versions of Bash. In addition, I can back out the change to the lit
built-in shell test runner to support this.

This should fix the majority of fallout on Darwin, but I suspect there
will be a few straggling issues.

llvm-svn: 159544
2012-07-02 18:37:59 +00:00
Chandler Carruth a5a29f970e Convert all tests using TCL-style quoting to use shell-style quoting.
This was done through the aid of a terrible Perl creation. I will not
paste any of the horrors here. Suffice to say, it require multiple
staged rounds of replacements, state carried between, and a few
nested-construct-parsing hacks that I'm not proud of. It happens, by
luck, to be able to deal with all the TCL-quoting patterns in evidence
in the LLVM test suite.

If anyone is maintaining large out-of-tree test trees, feel free to poke
me and I'll send you the steps I used to convert things, as well as
answer any painful questions etc. IRC works best for this type of thing
I find.

Once converted, switch the LLVM lit config to use ShTests the same as
Clang. In addition to being able to delete large amounts of Python code
from 'lit', this will also simplify the entire test suite and some of
lit's architecture.

Finally, the test suite runs 33% faster on Linux now. ;]
For my 16-hardware-thread (2x 4-core xeon e5520): 36s -> 24s

llvm-svn: 159525
2012-07-02 12:47:22 +00:00
Eli Bendersky 924f9a671d Replace all instances of dg.exp file with lit.local.cfg, since all tests are run with LIT now and now Dejagnu. dg.exp is no longer needed.
Patch reviewed by Daniel Dunbar. It will be followed by additional cleanup patches.

llvm-svn: 150664
2012-02-16 06:28:33 +00:00
Chris Lattner 6a144a2227 Upgrade syntax of tests using volatile instructions to use 'load volatile' instead of 'volatile load', which is archaic.
llvm-svn: 145171
2011-11-27 06:54:59 +00:00
Bill Wendling 63a4ea1859 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.

llvm-svn: 142221
2011-10-17 18:43:40 +00:00
Bill Wendling 42cf65fe51 Temporarily XFAIL waiting for a fix.
llvm-svn: 142215
2011-10-17 18:25:32 +00:00
Rafael Espindola 79d0c4f4b0 Check for the returns_twice attribute in callsFunctionThatReturnsTwice. This
fixes PR11038, but there are still some cleanups to be done.

llvm-svn: 141204
2011-10-05 20:05:13 +00:00
Rafael Espindola cc349c8dd8 Add the returns_twice attribute to LLVM.
llvm-svn: 141001
2011-10-03 14:45:37 +00:00
Bill Wendling 8bf0eab34d Replace uses of unwind with unreachable for the same effect.
llvm-svn: 140077
2011-09-19 22:16:15 +00:00
Bill Wendling 4aa2573748 Try to eliminate the use of the 'unwind' instruction.
llvm-svn: 139046
2011-09-02 22:41:11 +00:00
Chris Lattner 5756c16cdf make the asmparser reject function and type redefinitions. 'Merging' hasn't been
needed since llvm-gcc 3.4 days.

llvm-svn: 133248
2011-06-17 07:06:44 +00:00
Rafael Espindola 2050af838d Don't do tail calls in a function that call setjmp. The stack might be
corrupted when setjmp returns again.

llvm-svn: 131399
2011-05-16 03:05:33 +00:00
Evan Cheng 73c29178ac Add a test for TCE return duplication.
llvm-svn: 124527
2011-01-29 04:53:35 +00:00
Chris Lattner e2295f1c80 merge two tests.
llvm-svn: 112617
2010-08-31 18:44:03 +00:00
Chris Lattner fbcd165b59 merge two tests and convert to filecheck.
llvm-svn: 112613
2010-08-31 18:05:08 +00:00
Duncan Sands f88a284579 Handle the case of a tail recursion in which the tail call is followed
by a return that returns a constant, while elsewhere in the function
another return instruction returns a different constant.  This is a
special case of accumulator recursion, so just generalize the existing
logic a bit.

llvm-svn: 108241
2010-07-13 15:41:41 +00:00
Duncan Sands 3a5cb69cb8 Fix PR7328: when turning a tail recursion into a loop, need to preserve
the returned value after the tail call if it differs from other return
values.  The optimal thing to do would be to introduce a phi node for
the return value, but for the moment just fix the miscompile.

llvm-svn: 106947
2010-06-26 12:53:31 +00:00
Dan Gohman 99e5327bfd Refine the detection of seemingly infinitely recursive calls where the
callee is expected to be expanded to something else by codegen, so that
normal infinitely recursive calls are still transformed.

llvm-svn: 101468
2010-04-16 15:57:50 +00:00
Evan Cheng 27a41d5473 Revert 94937 and move the noreturn check to codegen.
llvm-svn: 95198
2010-02-03 03:55:59 +00:00
Evan Cheng d86d3fe0c3 Do not mark no-return calls tail calls. It'll screw up special calls like longjmp and it doesn't make much sense for performance reason. If my logic is faulty, please let me know.
llvm-svn: 94937
2010-01-31 00:59:31 +00:00
Dan Gohman fb4193625a Delete useless trailing semicolons.
llvm-svn: 92740
2010-01-05 17:55:26 +00:00
Nick Lewycky b9397262b7 Improve tail call elimination to handle the switch statement.
llvm-svn: 86403
2009-11-07 21:10:15 +00:00
Nick Lewycky 9b669b3c4f Oops, FunctionContainsEscapingAllocas is really used to mean two different
things. Back out part of r86349 for a moment.

llvm-svn: 86353
2009-11-07 07:42:38 +00:00
Nick Lewycky 5091272fdf Dust off tail recursion elimination. Fix a fixme by applying CaptureTracking
and add a .ll to demo the new capability.

llvm-svn: 86349
2009-11-07 07:10:01 +00:00
Dan Gohman a080159a7c Convert more tests to avoid llvm-as.
llvm-svn: 81545
2009-09-11 18:36:27 +00:00
Dan Gohman 0f3ef7be50 Eliminate more redundant llvm-as calls.
llvm-svn: 81540
2009-09-11 18:17:12 +00:00
Dan Gohman 1880092722 Change tests from "opt %s" to "opt < %s" so that opt doesn't see the
input filename so that opt doesn't print the input filename in the
output so that grep lines in the tests don't unintentionally match
strings in the input filename.

llvm-svn: 81537
2009-09-11 18:01:28 +00:00
Dan Gohman 72a13d2476 Use opt -S instead of piping bitcode output through llvm-dis.
llvm-svn: 81257
2009-09-08 22:34:10 +00:00
Dan Gohman 9737a63ed8 Change these tests to feed the assembly files to opt directly, instead
of using llvm-as, now that opt supports this.

llvm-svn: 81226
2009-09-08 16:50:01 +00:00
Chris Lattner 3b134cd72a tweak test, add PR#
llvm-svn: 81158
2009-09-07 22:14:41 +00:00
Daniel Dunbar b9ea94c990 Eliminate uses of %prcontext.
- I'd appreciate it if someone else eyeballs my changes to make sure I captured
   the intent of the test.

llvm-svn: 81083
2009-09-05 11:35:16 +00:00