Commit Graph

94 Commits

Author SHA1 Message Date
Edward O'Callaghan
4ea7d4c3eb Convert Analysis tests to FileCheck in regards to PR5307.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@85241 91177308-0d34-0410-b5e6-96231b3b80d8
2009-10-27 14:54:46 +00:00
Dan Gohman
1f96e67f78 Teach ScalarEvolution how to reason about no-wrap flags on loops
where the induction variable has a non-unit stride, such as {0,+,2}, and
there are expressions such as {1,+,2} inside the loop formed with
or or add nsw operators.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@82151 91177308-0d34-0410-b5e6-96231b3b80d8
2009-09-17 18:05:20 +00:00
Dan Gohman
f2f6ce65b7 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.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@81537 91177308-0d34-0410-b5e6-96231b3b80d8
2009-09-11 18:01:28 +00:00
Dan Gohman
3e054fe9ef Use opt -S instead of piping bitcode output through llvm-dis.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@81257 91177308-0d34-0410-b5e6-96231b3b80d8
2009-09-08 22:34:10 +00:00
Dan Gohman
b1e1e82c54 Change these tests to feed the assembly files to opt directly, instead
of using llvm-as, now that opt supports this.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@81226 91177308-0d34-0410-b5e6-96231b3b80d8
2009-09-08 16:50:01 +00:00
Dan Gohman
2385e0e22c Create a ScalarEvolution-based AliasAnalysis implementation.
This is a simple AliasAnalysis implementation which works by making
ScalarEvolution queries. ScalarEvolution has a more complete understanding
of arithmetic than BasicAA's collection of ad-hoc checks, so it handles
some cases that BasicAA misses, for example p[i] and p[i+1] within the
same iteration of a loop.

This is currently experimental. It may be that the main use for this pass
will be to help find cases where BasicAA can be profitably extended, or
to help in the development of the overall AliasAnalysis infrastructure,
however it's also possible that it could grow up to become a directly
useful pass.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@80098 91177308-0d34-0410-b5e6-96231b3b80d8
2009-08-26 14:53:06 +00:00
Dan Gohman
7a7be366a7 Loosen up the regex for this test so that it doesn't implicitly
depend on TargetData information.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@79491 91177308-0d34-0410-b5e6-96231b3b80d8
2009-08-19 23:19:36 +00:00
Dan Gohman
683e922d29 Make LLVM Assembly dramatically easier to read by aligning the comments,
using formatted_raw_ostream's PadToColumn.

Before:

bb1:            ; preds = %bb
  %2 = sext i32 %i.01 to i64            ; <i64> [#uses=1]
  %3 = getelementptr double* %p, i64 %2         ; <double*> [#uses=1]
  %4 = load double* %3, align 8         ; <double> [#uses=1]
  %5 = fmul double %4, 1.100000e+00             ; <double> [#uses=1]
  %6 = sext i32 %i.01 to i64            ; <i64> [#uses=1]
  %7 = getelementptr double* %p, i64 %6         ; <double*> [#uses=1]

After:

bb1:                                        ; preds = %bb
  %2 = sext i32 %i.01 to i64                ; <i64> [#uses=1]
  %3 = getelementptr double* %p, i64 %2     ; <double*> [#uses=1]
  %4 = load double* %3, align 8             ; <double> [#uses=1]
  %5 = fmul double %4, 1.100000e+00         ; <double> [#uses=1]
  %6 = sext i32 %i.01 to i64                ; <i64> [#uses=1]
  %7 = getelementptr double* %p, i64 %6     ; <double*> [#uses=1]

Several tests required whitespace adjustments.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@78816 91177308-0d34-0410-b5e6-96231b3b80d8
2009-08-12 17:23:50 +00:00
Dan Gohman
59858cf792 Change the assembly syntax for nsw, nuw, and exact, putting them
after their associated opcodes rather than before. This makes them
a little easier to read.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@77194 91177308-0d34-0410-b5e6-96231b3b80d8
2009-07-27 16:11:46 +00:00
Dan Gohman
19378d622e When attempting to sign-extend an addrec by interpreting
the step value as unsigned, the start value and the addrec
itself still need to be treated as signed.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@77078 91177308-0d34-0410-b5e6-96231b3b80d8
2009-07-25 16:03:30 +00:00
Dan Gohman
eb490a7aa3 Teach ScalarEvolution to make use of no-overflow flags when
analyzing add recurrences.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@77034 91177308-0d34-0410-b5e6-96231b3b80d8
2009-07-25 01:22:26 +00:00
Dan Gohman
0f4b285a5b Replace the original ad-hoc code for determining whether (v pred w) implies
(x pred y) with more thorough code that does more complete canonicalization
before resorting to range checks. This helps it find more cases where
the canonicalized expressions match.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@76671 91177308-0d34-0410-b5e6-96231b3b80d8
2009-07-21 23:03:19 +00:00
Dan Gohman
19211b47cc Add a testcase for PR4569, which is now fixed.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@76526 91177308-0d34-0410-b5e6-96231b3b80d8
2009-07-21 00:50:52 +00:00
Dan Gohman
08d4ec0b20 Add testcases for PR4538, PR4537, and PR4534.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@75533 91177308-0d34-0410-b5e6-96231b3b80d8
2009-07-13 22:30:31 +00:00
Nick Lewycky
d1ec98923e When comparing constants, consider a less wide constant to be "less complex"
than a wider one, before trying to compare their contents which will crash
if their sizes are different.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@74792 91177308-0d34-0410-b5e6-96231b3b80d8
2009-07-04 17:24:52 +00:00
Dan Gohman
e56f4a49b7 Add a testcase demoing some of ScalarEvolution's new trip count logic.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@74049 91177308-0d34-0410-b5e6-96231b3b80d8
2009-06-24 01:22:30 +00:00
Dan Gohman
91380b7239 Fix a bug in the trip-count computation with And/Or. If either of the
sides is CouldNotCompute, the resulting exact count must be CouldNotCompute.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@73920 91177308-0d34-0410-b5e6-96231b3b80d8
2009-06-22 23:28:56 +00:00
Dan Gohman
bd5ce52740 Fix llvm::ComputeNumSignBits to handle pointer types
conservatively correctly, instead of aborting.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@73908 91177308-0d34-0410-b5e6-96231b3b80d8
2009-06-22 22:02:32 +00:00
Dan Gohman
a334aa7a10 Teach ScalarEvolution how to analyze loops with multiple exit
blocks, and also exit blocks with multiple conditions (combined
with (bitwise) ands and ors). It's often infeasible to compute an
exact trip count in such cases, but a useful upper bound can often
be found.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@73866 91177308-0d34-0410-b5e6-96231b3b80d8
2009-06-22 00:31:57 +00:00
Dan Gohman
51f53b7f5a Fix ScalarEvolution's backedge-taken count computations to check for
overflow when computing a integer division to round up.

Thanks to Nick Lewycky for noticing this!


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@73862 91177308-0d34-0410-b5e6-96231b3b80d8
2009-06-21 23:46:38 +00:00
Dan Gohman
820528331f Teach ScalarEvolution how to recognize another xor(and(x, C), C) case.
If C is a single bit and the and gets analyzed as a truncate and
zero-extend, the xor can be represnted as an add.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@73664 91177308-0d34-0410-b5e6-96231b3b80d8
2009-06-18 00:00:20 +00:00
Dan Gohman
559254b697 Add -disable-output to a bunch of tests that don't care about the output.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@73633 91177308-0d34-0410-b5e6-96231b3b80d8
2009-06-17 20:56:26 +00:00
Dan Gohman
3034c10675 Fix ScalarEvolution's Xor handling to not assume that an And
that gets recognized with a SCEVZeroExtendExpr must be an And
with a low-bits mask. With r73540, this is no longer the case.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@73594 91177308-0d34-0410-b5e6-96231b3b80d8
2009-06-17 01:22:39 +00:00
Dan Gohman
ae3a0be92e Split the Add, Sub, and Mul instruction opcodes into separate
integer and floating-point opcodes, introducing
FAdd, FSub, and FMul.

For now, the AsmParser, BitcodeReader, and IRBuilder all preserve
backwards compatability, and the Core LLVM APIs preserve backwards
compatibility for IR producers. Most front-ends won't need to change
immediately.

This implements the first step of the plan outlined here:
http://nondot.org/sabre/LLVMNotes/IntegerOverflow.txt


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@72897 91177308-0d34-0410-b5e6-96231b3b80d8
2009-06-04 22:49:04 +00:00
Dan Gohman
10978bd591 Teach ScalarEvolution to recognize x^-1 in the case where non-demanded
bits have been stripped out by instcombine.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@72010 91177308-0d34-0410-b5e6-96231b3b80d8
2009-05-18 16:29:04 +00:00
Dan Gohman
859b4824ee Make ScalarEvolution::isLoopGuardedByCond work even when the edge
entering a loop is a non-split critical edge.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@72004 91177308-0d34-0410-b5e6-96231b3b80d8
2009-05-18 15:36:09 +00:00
Dan Gohman
04623272d2 Add nounwind to a few tests.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@72002 91177308-0d34-0410-b5e6-96231b3b80d8
2009-05-18 15:16:49 +00:00
Eli Friedman
361e54d433 Allow scalar evolution to compute iteration counts for loops with a
pointer-based condition.  This fixes PR3171.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@71354 91177308-0d34-0410-b5e6-96231b3b80d8
2009-05-09 12:32:42 +00:00
Dan Gohman
b0285932ab Fix bogus overflow checks by replacing them with actual
overflow checks.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@71284 91177308-0d34-0410-b5e6-96231b3b80d8
2009-05-08 23:11:16 +00:00
Dan Gohman
728c7f3059 Fold trunc casts into add-recurrence expressions, allowing the
add-recurrence to be exposed. Add a new SCEV folding rule to
help simplify expressions in the presence of these extra truncs.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@71264 91177308-0d34-0410-b5e6-96231b3b80d8
2009-05-08 21:03:19 +00:00
Dan Gohman
9032b78c98 When printing a SCEVUnknown with pointer type, don't print an
artificial "ptrtoint", as it tends to clutter up complicated
expressions. The cast operators now print both source and
destination types, which is usually sufficient.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@70554 91177308-0d34-0410-b5e6-96231b3b80d8
2009-05-01 17:02:22 +00:00
Dan Gohman
a1af757e0a Extend ScalarEvolution's getBackedgeTakenCount to be able to
compute an upper-bound value for the trip count, in addition to
the actual trip count. Use this to allow getZeroExtendExpr and
getSignExtendExpr to fold casts in more cases.

This may eventually morph into a more general value-range
analysis capability; there are certainly plenty of places where
more complete value-range information would allow more folding.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@70509 91177308-0d34-0410-b5e6-96231b3b80d8
2009-04-30 20:47:05 +00:00
Dan Gohman
ac70ceafbc Generalize the cast-of-addrec folding to handle folding of SCEVs like
(sext i8 {-128,+,1} to i64) to i64 {-128,+,1}, where the iteration
crosses from negative to positive, but is still safe if the trip
count is within range.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@70421 91177308-0d34-0410-b5e6-96231b3b80d8
2009-04-29 22:28:28 +00:00
Dan Gohman
3e0e31b261 Fix this test to match the new output from scalar-evolution.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@70410 91177308-0d34-0410-b5e6-96231b3b80d8
2009-04-29 21:06:20 +00:00
Dan Gohman
36b8e53fe0 Include the source type in SCEV cast expression debug output, and
print sext, zext, and trunc, instead of signextend, zeroextend,
and truncate, respectively, for consistency with the main IR.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@70405 91177308-0d34-0410-b5e6-96231b3b80d8
2009-04-29 20:27:52 +00:00
Dan Gohman
87d2fe5143 Fix a grammaro in a comment.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@70331 91177308-0d34-0410-b5e6-96231b3b80d8
2009-04-28 21:54:23 +00:00
Nick Lewycky
5cd28fad15 Simplify trunc(extend(x)) in SCEVs, just for completeness. Also fix some odd
whitespace in the same file.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@69870 91177308-0d34-0410-b5e6-96231b3b80d8
2009-04-23 05:15:08 +00:00
Owen Anderson
03dac74d40 Testcase for PR3909.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@69868 91177308-0d34-0410-b5e6-96231b3b80d8
2009-04-23 04:33:42 +00:00
Dan Gohman
578ccf81e5 When turning (ashr(shl(x, n), n)) into sext(trunc(x)), the width of the
type to truncate to should be the number of bits of the value that are
preserved, not the number that are clobbered with sign-extension.
This fixes regressions in ldecod.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@69704 91177308-0d34-0410-b5e6-96231b3b80d8
2009-04-21 20:18:36 +00:00
Dan Gohman
46bdfb0e6b Rename ScalarEvolution's getIterationCount to getBackedgeTakenCount,
to more accurately describe what it does. Expand its doxygen comment
to describe what the backedge-taken count is and how it differs
from the actual iteration count of the loop. Adjust names and
comments in associated code accordingly.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@65382 91177308-0d34-0410-b5e6-96231b3b80d8
2009-02-24 18:55:53 +00:00
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
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
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
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
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