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
SCEVUnknowns, as the non-SCEVUnknown cases in the getSCEVAtScope code
can also end up repeatedly climing through the same expression trees,
which can be unusably slow when the trees are very tall.
Also, add a quick check for SCEV pointer equality to the main
SCEV comparison routine, as the full comparison code can be expensive
in the case of large expression trees.
These fix compile-time problems in some pathlogical cases.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@80623 91177308-0d34-0410-b5e6-96231b3b80d8
will always return the same value. This isn't currently necessary,
since this code doesn't currently ever get called under circumstances
where it would matter, but it may some day.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@80017 91177308-0d34-0410-b5e6-96231b3b80d8
by hand, and fix a few places that were using hasInitializer() that
appear to depend on the initializer value.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@79441 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
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
affected after a PHI node has been analyzed, just remove affected
SCEVs from the Scalars map, so that they'll be (lazily) recreated as
needed. This avoids creating SCEV objects that aren't actually needed.
Also, rewrite the associated def-use walking code to be non-recursive
and to continue traversing past Instructions that don't have an
entry in the Scalars map.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@77032 91177308-0d34-0410-b5e6-96231b3b80d8
(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
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
in a convenient manner, factoring out some common code from
InstructionCombining and ValueTracking. Move the contents of
BinaryOperators.h into Operator.h and use Operator to generalize them
to support ConstantExprs as well as Instructions.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@76232 91177308-0d34-0410-b5e6-96231b3b80d8
This adds location info for all llvm_unreachable calls (which is a macro now) in
!NDEBUG builds.
In NDEBUG builds location info and the message is off (it only prints
"UREACHABLE executed").
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@75640 91177308-0d34-0410-b5e6-96231b3b80d8
check for avoiding re-analyzing a widening cast needed to happen
earlier, as getSCEV itself may result in a isLoopGuardedByCond query.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@75511 91177308-0d34-0410-b5e6-96231b3b80d8
SCEVZeroExtendExpr ahead of the most expensive analysis. This
speeds up analysis and helps avoid pathologically bad behavior
on the testcase in PR4534.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@75496 91177308-0d34-0410-b5e6-96231b3b80d8
