Commit Graph

258 Commits

Author SHA1 Message Date
Nick Lewycky
789558db70 Wind SCEV back in time, to Nov 18th. This 'fixes' PR3275, PR3294, PR3295,
PR3296 and PR3302.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@62160 91177308-0d34-0410-b5e6-96231b3b80d8
2009-01-13 09:18:58 +00:00
Nick Lewycky
ae285bf5a6 Don't try to analyze this "backward" case. This is overly conservative
pending a correct solution.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@61589 91177308-0d34-0410-b5e6-96231b3b80d8
2009-01-02 18:54:17 +00:00
Nick Lewycky
3037eda1ef Check that the function prototypes are correct before assuming that the
parameters are pointers.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@61451 91177308-0d34-0410-b5e6-96231b3b80d8
2008-12-27 16:20:53 +00:00
Nick Lewycky
f23d0d392a Resubmit support for the 'nocapture' attribute.
The problematic part of this patch is that we were out of attribute bits,
requiring some fancy bit hacking to make it fit (by shrinking alignment)
without breaking existing users or the file format.

This change will require users to rebuild llvm-gcc to match llvm.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@61239 91177308-0d34-0410-b5e6-96231b3b80d8
2008-12-19 06:39:12 +00:00
Bill Wendling
43445c153c Remove empty test.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@61095 91177308-0d34-0410-b5e6-96231b3b80d8
2008-12-16 19:07:17 +00:00
Bill Wendling
6fa311c233 Temporarily revert r61019, r61030, and r61040. These were breaking LLVM Release
builds.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@61094 91177308-0d34-0410-b5e6-96231b3b80d8
2008-12-16 19:06:48 +00:00
Nick Lewycky
1447f5ca1f Generalize support for analyzing loops to include SLE/SGE loop exit conditions
and support for non-unit strides with signed exit conditions.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@61082 91177308-0d34-0410-b5e6-96231b3b80d8
2008-12-16 08:30:01 +00:00
Chris Lattner
1314f20283 Teach basicaa to use the nocapture attribute when possible. When the
intrinsics are properly marked nocapture, the fixme should be addressed.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@61040 91177308-0d34-0410-b5e6-96231b3b80d8
2008-12-15 18:59:22 +00:00
Nick Lewycky
8bdc6920cd Revert my re-instated reverted commit, fixes the bootstrap build on x86-64 linux.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@60951 91177308-0d34-0410-b5e6-96231b3b80d8
2008-12-12 17:09:07 +00:00
Nick Lewycky
277a147f87 Sneaky, sneaky: move the -1 to the outside of the SMax. Reinstate the
optimization of SGE/SLE with unit stride, now that it works properly.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@60881 91177308-0d34-0410-b5e6-96231b3b80d8
2008-12-11 17:40:14 +00:00
Chris Lattner
b957bda0bc Allow basicaa to walk through geps with identical indices in
parallel, allowing it to decide that P/Q must alias if A/B
must alias in things like:
 P = gep A, 0, i, 1
 Q = gep B, 0, i, 1

This allows GVN to delete 62 more instructions out of 403.gcc.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@60820 91177308-0d34-0410-b5e6-96231b3b80d8
2008-12-10 01:04:47 +00:00
Evan Cheng
28575f2113 xfail this for now.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@60777 91177308-0d34-0410-b5e6-96231b3b80d8
2008-12-09 18:43:00 +00:00
Nick Lewycky
0bed364307 It's easy to handle SLE/SGE when the loop has a unit stride.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@60748 91177308-0d34-0410-b5e6-96231b3b80d8
2008-12-09 07:25:04 +00:00
Nick Lewycky
02ff308aa1 Extend the 'noalias' attribute to function return values. This is intended to
indicate functions that allocate, such as operator new, or list::insert. The
actual definition is slightly less strict (for now).

No changes to the bitcode reader/writer, asm printer or verifier were needed.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@59934 91177308-0d34-0410-b5e6-96231b3b80d8
2008-11-24 03:41:24 +00:00
Nick Lewycky
dd643f26c4 Add a utility function that detects whether a loop is guaranteed to be finite.
Use it to safely handle less-than-or-equals-to exit conditions in loops. These
also occur when the loop exit branch is exit on true because SCEV inverses the
icmp predicate.

Use it again to handle non-zero strides, but only with an unsigned comparison
in the exit condition.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@59528 91177308-0d34-0410-b5e6-96231b3b80d8
2008-11-18 15:10:54 +00:00
Nick Lewycky
d72a81ee64 Don't brute-force analyze cubic or higher polynomials.
If this patch causes a performance regression for anyone, please let me know,
and it can be fixed in a different way with much more effort.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@59384 91177308-0d34-0410-b5e6-96231b3b80d8
2008-11-16 04:14:25 +00:00
Nick Lewycky
8f4d5eb9e5 Don't crash analyzing certain quadratics (addrec of {X,+,Y,+,1}).
We're still waiting on code that actually analyzes them properly.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@58592 91177308-0d34-0410-b5e6-96231b3b80d8
2008-11-03 02:43:49 +00:00
Duncan Sands
3ee8fc9649 Rationalize the names of passes that print information:
-callgraph => print-callgraph
    -callscc   => print-callgraph-sccs
    -cfgscc    => print-cfg-sccs
    -externalfnconstants => print-externalfnconstants
    -print               => print-function
    -print-alias-sets (no change)
    -print-callgraph     => dot-callgraph
    -print-cfg           => dot-cfg
    -print-cfg-only      => dot-cfg-only
    -print-dom-info (no change)
    -printm              => print-module
    -printusedtypes      => print-used-types


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@56487 91177308-0d34-0410-b5e6-96231b3b80d8
2008-09-23 12:47:39 +00:00
Duncan Sands
acdb2eeb45 Remove the MarkModRef pass (use AddReadAttrs instead).
Unfortunately this means removing one regression test
of GlobalsModRef because I couldn't work out how to
perform it without MarkModRef.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@56342 91177308-0d34-0410-b5e6-96231b3b80d8
2008-09-19 08:23:44 +00:00
Duncan Sands
9f07a290b9 Add a new pass AddReadAttrs which works out which functions
can get the readnone/readonly attributes, and gives them it.
The plan is to remove markmodref (which did the same thing
by querying GlobalsModRef) and delete the analogous
functionality from GlobalsModRef.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@56341 91177308-0d34-0410-b5e6-96231b3b80d8
2008-09-19 08:17:05 +00:00
Duncan Sands
e65d39a42c Teach -callgraph to always print the callgraph (as the
description says it does), not just when -analyze is
used as well.  This means printing to stderr, so adjust
some tests.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@56337 91177308-0d34-0410-b5e6-96231b3b80d8
2008-09-19 07:57:09 +00:00
Dan Gohman
70ff4cf1ba Finally re-apply r46959. This is made feasible by the combination
of r56230, r56232, and r56246.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@56247 91177308-0d34-0410-b5e6-96231b3b80d8
2008-09-16 18:52:57 +00:00
Dan Gohman
c7e42fd5b2 Fix spacing in the grep line for this test, following the recent
SCEV-whitespace changes.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@56234 91177308-0d34-0410-b5e6-96231b3b80d8
2008-09-16 01:37:08 +00:00
Dan Gohman
fd6edef87b Teach ScalarEvolution to consider loop preheaders in the search for
an if statement that guards a loop, to allow indvars to avoid smax
operations in more situations.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@56232 91177308-0d34-0410-b5e6-96231b3b80d8
2008-09-15 22:18:04 +00:00
Dan Gohman
8dae138d06 Fix WriteAsOperand to not emit a leading space character. Adjust
its callers to emit a space character before calling it when a
space is needed.

This fixes several spurious whitespace issues in
ScalarEvolution's debug dumps. See the test changes for
examples.

This also fixes odd space-after-tab indentation in the output
for switch statements, and changes calls from being printed like
this:
  call void @foo( i32 %x )
to this:
  call void @foo(i32 %x)


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@56196 91177308-0d34-0410-b5e6-96231b3b80d8
2008-09-14 17:21:12 +00:00
Duncan Sands
b8ca4ff643 Fix PR2792: treat volatile loads as writing memory somewhere.
Treat stores as reading memory, just to play safe.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@56188 91177308-0d34-0410-b5e6-96231b3b80d8
2008-09-13 12:45:50 +00:00
Duncan Sands
99c1a7c9e1 Correct callgraph construction. It has two problems:
(1) code left over from the days of ConstantPointerRef:
if a use of a function is a GlobalValue then that is
not considered a reason to add an edge from the external
node, even though the use may be as an initializer for
an externally visible global!  There might be some point
to this behaviour when the use is by an alias (though the
code predated aliases by some centuries), but I think
PR2782 is a better way of handling that.  (2) If function
F calls function G, and also G is a parameter to the
call, then an F->G edge is not added to the callgraph.
While this doesn't seem to matter much, adding such an
edge makes the callgraph more regular.
In addition, the new code should be faster as well as
simpler.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@55987 91177308-0d34-0410-b5e6-96231b3b80d8
2008-09-09 12:40:47 +00:00
Duncan Sands
faf600a9ed Testcase for commits 55700 and 55714.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@55715 91177308-0d34-0410-b5e6-96231b3b80d8
2008-09-03 19:38:41 +00:00
Duncan Sands
d0ac373660 Since onlyReadsMemory returns true if in fact
doesNotAccessMemory, check doesNotAccessMemory
first, since otherwise functions may be
marked readonly rather than readnone.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@55697 91177308-0d34-0410-b5e6-96231b3b80d8
2008-09-03 15:31:24 +00:00
Duncan Sands
9a036b945c Cleanup GlobalsModRef a bit. When analysing the
callgraph, when one member of a SCC calls another
then the analysis would drop to mod-ref because
there is (usually) no function info for the callee
yet; fix this.  Teach the analysis about function
attributes, in particular the readonly attribute
(which requires being careful about globals).


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@55696 91177308-0d34-0410-b5e6-96231b3b80d8
2008-09-03 12:55:42 +00:00
Owen Anderson
7c856c09cd Remove GCSE and LoadVN from the testsuite.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@54832 91177308-0d34-0410-b5e6-96231b3b80d8
2008-08-16 00:00:54 +00:00
Dan Gohman
3837218ea0 Extend ScalarEvolution's executesAtLeastOnce logic to be able to
continue past the first conditional branch when looking for a
relevant test. This helps it avoid using MAX expressions in
loop trip counts in more cases.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@54697 91177308-0d34-0410-b5e6-96231b3b80d8
2008-08-12 20:17:31 +00:00
Eli Friedman
b42a626122 PR2621: Improvements to the SCEV AddRec binomial expansion. This
version uses a new algorithm for evaluating the binomial coefficients 
which is significantly more efficient for AddRecs of more than 2 terms 
(see the comments in the code for details on how the algorithm works).  
It also fixes some bugs: it removes the arbitrary length restriction for 
AddRecs, it fixes the silent generation of incorrect code for AddRecs 
which require a wide calculation width, and it fixes an issue where we 
were incorrectly truncating the iteration count too far when evaluating 
an AddRec expression narrower than the induction variable.

There are still a few related issues I know of: I think there's 
still an issue with the SCEVExpander expansion of AddRec in terms of
the width of the induction variable used.  The hack to avoid generating 
too-wide integers shouldn't be necessary; instead, the callers should be 
considering the cost of the expansion before expanding it (in addition 
to not expanding too-wide integers, we might not want to expand 
expressions that are really expensive, especially when optimizing for 
size; calculating an length-17 32-bit AddRec currently generates about 250 
instructions of straight-line code on X86).  Also, for long 32-bit 
AddRecs on X86, CodeGen really sucks at scheduling the code.  I'm planning on 
filing follow-up PRs for these issues.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@54332 91177308-0d34-0410-b5e6-96231b3b80d8
2008-08-04 23:49:06 +00:00
Eli Friedman
1fbffe0cef Another SCEV issue from PR2607; essentially the same issue, but this
time applying to the implicit comparison in smin expressions. The 
correct way to transform an inequality into the opposite 
inequality, either signed or unsigned, is with a not expression.

I looked through the SCEV code, and I don't think there are any more 
occurrences of this issue.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@54194 91177308-0d34-0410-b5e6-96231b3b80d8
2008-07-30 04:36:32 +00:00
Eli Friedman
068acc3caa Fix for PR2607: SCEV miscomputing the loop count for loops with an
SGT exit condition.  Essentially, the correct way to flip an inequality 
in 2's complement is the not operator, not the negation operator.  
That said, the difference only affects cases involving INT_MIN.

Also, enhance the pre-test search logic to be a bit smarter about 
inequalities flipped with a not operator, so it can eliminate the smax 
from the iteration count for simple loops.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@54184 91177308-0d34-0410-b5e6-96231b3b80d8
2008-07-30 00:04:08 +00:00
Wojciech Matyjewicz
de0f2382e4 Fix PR2088. Use modulo linear equation solver to compute loop iteration
count.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@53810 91177308-0d34-0410-b5e6-96231b3b80d8
2008-07-20 15:55:14 +00:00
Nick Lewycky
e637727bed XFAIL this test.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@53793 91177308-0d34-0410-b5e6-96231b3b80d8
2008-07-19 15:52:06 +00:00
Wojciech Matyjewicz
5c779a46b0 While testing particular algorithms to compute loop iteration count the brute
force evaluation (ComputeIterationCountExhaustively) should be turned off.

It doesn't apply to trip-count2.ll because this file tests the brute force
evaluation.

The test for PR2364 (2008-05-25-NegativeStepToZero.ll) currently fails
showing that the patch for this bug doesn't work. I'll fix it in a few hours
with a patch for PR2088.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@53792 91177308-0d34-0410-b5e6-96231b3b80d8
2008-07-19 13:26:15 +00:00
Nick Lewycky
59cff12f88 Stop creating extraneous smax/umax in SCEV. This removes a regression where we
started complicating many loops ('for' loops, in fact).


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@53508 91177308-0d34-0410-b5e6-96231b3b80d8
2008-07-12 07:41:32 +00:00
Chris Lattner
845f0d2f0f If we are checking to see if the result of a call aliases a
pointer derived from a local allocation, if the local allocation
never escapes, the pointers can't alias.  This implements PR2436


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@52301 91177308-0d34-0410-b5e6-96231b3b80d8
2008-06-16 06:19:11 +00:00
Nick Lewycky
6f8abf929a Crash less. The i64 restriction in BinomialCoefficient caused some problems
with code that was expecting different bit widths for different values.

Make getTruncateOrZeroExtend a method on ScalarEvolution, and use it.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@52248 91177308-0d34-0410-b5e6-96231b3b80d8
2008-06-13 04:38:55 +00:00
Matthijs Kooijman
da8bdfa92b Remove trailing whitespace after line continuations in test cases to them work.
This fixes two test cases that were not being run properly before.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@52179 91177308-0d34-0410-b5e6-96231b3b80d8
2008-06-10 15:07:07 +00:00
Matthijs Kooijman
f167bc2922 Suppress the (stderr) output of -aa-eval, this fixes 5 tests.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@52173 91177308-0d34-0410-b5e6-96231b3b80d8
2008-06-10 12:39:15 +00:00
Wojciech Matyjewicz
98e3a6829a Fixes PR2395. Looking for a constant in a GEP tail (when the first GEP
is longer than the second one) should stop after finding one. Added break 
instruction guarantees it. It also changes difference between offsets to 
absolute value of this difference in the condition.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@51875 91177308-0d34-0410-b5e6-96231b3b80d8
2008-06-02 17:26:12 +00:00
Owen Anderson
8cacfebb8e Move these tests into the proper directory.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@51685 91177308-0d34-0410-b5e6-96231b3b80d8
2008-05-29 16:30:29 +00:00
Nick Lewycky
aadc6b68c7 Whoops -- forgot PR reference on this test.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@51569 91177308-0d34-0410-b5e6-96231b3b80d8
2008-05-26 20:23:33 +00:00
Nick Lewycky
505242f9b6 Use {} instead of "" in RUN lines.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@51561 91177308-0d34-0410-b5e6-96231b3b80d8
2008-05-26 01:27:08 +00:00
Nick Lewycky
04b35e8532 Don't treat values as signed when looking at loop steppings in HowForToNonZero.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@51560 91177308-0d34-0410-b5e6-96231b3b80d8
2008-05-25 23:43:32 +00:00
Dan Gohman
3bf19e4c42 Remove lingering references to .llx and .tr in the tests.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@51500 91177308-0d34-0410-b5e6-96231b3b80d8
2008-05-23 21:15:35 +00:00
Gabor Greif
f6cadc440c sabre brings to my attention that the 'tr' suffix is also obsolete
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@51349 91177308-0d34-0410-b5e6-96231b3b80d8
2008-05-20 21:00:03 +00:00