Modified LinearFunctionTestReplace to push the condition on the dead
list instead of eagerly deleting it. This can cause unnecessary
IV rewrites, which should have no effect on codegen and will not be an
issue once we stop generating canonical IVs.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@130340 91177308-0d34-0410-b5e6-96231b3b80d8
For example, on 32-bit architecture, don't promote all uses of the IV
to 64-bits just because one use is a 64-bit cast.
Alternate implementation of the patch by Arnaud de Grandmaison.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@127884 91177308-0d34-0410-b5e6-96231b3b80d8
it inserted rather than using LoopInfo::getCanonicalInductionVariable to
rediscover it, since that doesn't work on non-canonical loops. This fixes
infinite recurrsion on such loops; PR7562.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@109419 91177308-0d34-0410-b5e6-96231b3b80d8
it doesn't miss an opportunity to form a GEP, regardless of the
relative loop depths of the operands. This fixes rdar://8197217.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@108475 91177308-0d34-0410-b5e6-96231b3b80d8
just ask ScalarEvolution for it on demand. This helps IVUsers be more robust
in the case of expressions changing underneath it. This fixes PR6862.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@101819 91177308-0d34-0410-b5e6-96231b3b80d8
numerator is an induction variable. For example, with code like this:
for (i=0;i<n;++i)
x[i%n] = 0;
IndVarSimplify will now recognize that i is always less than n inside
the loop, and eliminate the remainder.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@101113 91177308-0d34-0410-b5e6-96231b3b80d8
expression is a UDiv and it doesn't appear that the UDiv came from
the user's source.
ScalarEvolution has recently figured out how to compute a tripcount
expression for the inner loop in
SingleSource/Benchmarks/Shootout/sieve.c, using a udiv. Emitting a
udiv instruction dramatically slows down the enclosing loop.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@101068 91177308-0d34-0410-b5e6-96231b3b80d8
the loop exit test. This usually doesn't come up for a variety of
reasons, but it isn't impossible, so make IndVarSimplify handle it
conservatively.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@101008 91177308-0d34-0410-b5e6-96231b3b80d8
variables. For example, with code like this:
for (i=0;i<n;++i)
if (i<n)
x[i] = 0;
IndVarSimplify will now recognize that i is always less than n inside
the loop, and eliminate the if.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@101000 91177308-0d34-0410-b5e6-96231b3b80d8
checker. Amusingly, we already had tests that we should
have rejects because they would be miscompiled in the
testsuite.
The remaining issue with this is that we don't check that
the branch causes us to exit the loop if it fails, so we
don't actually know if we remain in bounds.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@100284 91177308-0d34-0410-b5e6-96231b3b80d8
this cleans up a bunch of code and also fixes several crashes and
miscompiles. More to come unfortunately, this optimization
is quite broken.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@100270 91177308-0d34-0410-b5e6-96231b3b80d8
which branch on undef to branch on a boolean constant for the edge
exiting the loop. This helps ScalarEvolution compute trip counts for
loops.
Teach ScalarEvolution to recognize single-value PHIs, when safe, and
ForgetSymbolicName to forget such single-value PHI nodes as apprpriate
in ForgetSymbolicName.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@97126 91177308-0d34-0410-b5e6-96231b3b80d8
true or false as its exit condition. These are usually eliminated by
SimplifyCFG, but the may be left around during a pass which wishes
to preserve the CFG.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@96683 91177308-0d34-0410-b5e6-96231b3b80d8
bug fixes, and with improved heuristics for analyzing foreign-loop
addrecs.
This change also flattens IVUsers, eliminating the stride-oriented
groupings, which makes it easier to work with.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@95975 91177308-0d34-0410-b5e6-96231b3b80d8
This new version is much more aggressive about doing "full" reduction in
cases where it reduces register pressure, and also more aggressive about
rewriting induction variables to count down (or up) to zero when doing so
reduces register pressure.
It currently uses fairly simplistic algorithms for finding reuse
opportunities, but it introduces a new framework allows it to combine
multiple strategies at once to form hybrid solutions, instead of doing
all full-reduction or all base+index.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@94061 91177308-0d34-0410-b5e6-96231b3b80d8
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
- I'd appreciate it if someone else eyeballs my changes to make sure I captured
the intent of the test.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@81083 91177308-0d34-0410-b5e6-96231b3b80d8
sinking code, since they are special. If the loop preheader happens
to be the entry block of a function, don't sink static allocas
out of it. This fixes PR4775.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@80010 91177308-0d34-0410-b5e6-96231b3b80d8
TargetData is not present. It still uses TargetData when available.
This generalization also fixed some limitations in the TargetData
case; the attached testcase covers this.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@79344 91177308-0d34-0410-b5e6-96231b3b80d8
Getelementptrs that are defined to wrap are virtually useless to
optimization, and getelementptrs that are undefined on any kind
of overflow are too restrictive -- it's difficult to ensure that
all intermediate addresses are within bounds. I'm going to take
a different approach.
Remove a few optimizations that depended on this flag.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@76437 91177308-0d34-0410-b5e6-96231b3b80d8
