Commit Graph

165 Commits

Author SHA1 Message Date
Dan Gohman
cab9cf01ce Make this testcase slightly less trivial, so that it doesn't fail
if indvars happens to optimize away the unused primary induction
variable.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@70333 91177308-0d34-0410-b5e6-96231b3b80d8
2009-04-28 22:03:26 +00:00
Dale Johannesen
617d108a63 Fix PR 4086, a bug in FP IV elimination.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@70247 91177308-0d34-0410-b5e6-96231b3b80d8
2009-04-27 21:03:15 +00:00
Dan Gohman
d6c329532b Handle ands with ~0 correctly too. This fixes PR4052.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@70176 91177308-0d34-0410-b5e6-96231b3b80d8
2009-04-27 01:41:10 +00:00
Dan Gohman
2c73d5fb9e Handle ands with 0 and shifts by 0 correctly. These aren't
common, but indvars shouldn't crash on them. This fixes PR4054.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@70051 91177308-0d34-0410-b5e6-96231b3b80d8
2009-04-25 17:05:40 +00:00
Dan Gohman
e22d503ee5 Fix an error in this test.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@69893 91177308-0d34-0410-b5e6-96231b3b80d8
2009-04-23 15:22:28 +00:00
Dan Gohman
752ec7da50 Change SCEVExpander's expandCodeFor to provide more flexibility
with the persistent insertion point, and change IndVars to make
use of it. This fixes a bug where IndVars was holding on to a
stale insertion point and forcing the SCEVExpander to continue to
use it.

This fixes PR4038.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@69892 91177308-0d34-0410-b5e6-96231b3b80d8
2009-04-23 15:16:49 +00:00
Evan Cheng
9c15949967 Make sure both operands have binary instructions have the same type.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@69844 91177308-0d34-0410-b5e6-96231b3b80d8
2009-04-22 23:39:28 +00:00
Evan Cheng
1abe64663e Avoid deferencing use_begin() if value does not have a use.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@69836 91177308-0d34-0410-b5e6-96231b3b80d8
2009-04-22 22:45:37 +00:00
Dan Gohman
aabb04f527 SCEVExpander's InsertCastOfTo knows how to move existing cast
instructions in order to avoid inserting new ones. However, if
the cast instruction is the SCEVExpander's InsertPt, this
causes subsequently emitted instructions to be inserted near
the cast, and not at the location of the original insert point.
Fix this by adjusting the insert point in such cases.
This fixes PR4009.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@69808 91177308-0d34-0410-b5e6-96231b3b80d8
2009-04-22 16:11:16 +00:00
Dale Johannesen
764eccf025 Another testcase for IV shortening.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@69247 91177308-0d34-0410-b5e6-96231b3b80d8
2009-04-16 00:45:21 +00:00
Dale Johannesen
dd1f9e4bf6 Enhance induction variable code to remove the
sext around sext(shorter IV + constant), using a
longer IV instead, when it can figure out the
add can't overflow.  This comes up a lot in
subscripting; mainly affects 64 bit.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@69123 91177308-0d34-0410-b5e6-96231b3b80d8
2009-04-15 01:10:12 +00:00
Dan Gohman
15cab2817b Back out the change in 64918 that used sign-extensions when promoting
trip counts that use signed comparisons. It's not obviously the best
approach for preserving trip count information, and at any rate there
isn't anything in the tree right now that makes use of that, so for
now always using zero-extensions is preferable.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@65347 91177308-0d34-0410-b5e6-96231b3b80d8
2009-02-23 23:20:35 +00:00
Dan Gohman
f5a309e989 Use a sign-extend instead of a zero-extend when promoting a
trip count value when the original loop iteration condition is
signed and the canonical induction variable won't undergo signed
overflow. This isn't required for correctness; it just preserves
more information about original loop iteration values.

Add a getTruncateOrSignExtend method to ScalarEvolution,
following getTruncateOrZeroExtend.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@64918 91177308-0d34-0410-b5e6-96231b3b80d8
2009-02-18 17:22:41 +00:00
Dan Gohman
d2067fd730 Fix a corner case in the new indvars promotion logic: if there
are multiple IV's in a loop, some of them may under go signed
or unsigned wrapping even if the IV that's used in the loop
exit condition doesn't. Restrict sign-extension-elimination
and zero-extension-elimination to only those that operate on
the original loop-controlling IV.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@64866 91177308-0d34-0410-b5e6-96231b3b80d8
2009-02-18 00:52:00 +00:00
Dan Gohman
74786c0f43 Rename IndVarsSimplify to IndVarSimplify, to be consistent with
the name used in the code that these tests are for.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@64624 91177308-0d34-0410-b5e6-96231b3b80d8
2009-02-16 00:56:15 +00:00