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.
llvm-svn: 82151
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.
llvm-svn: 80623
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.
llvm-svn: 80017
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.
llvm-svn: 79344
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.
llvm-svn: 77032
(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.
llvm-svn: 76671
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.
llvm-svn: 76437
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.
llvm-svn: 76232
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").
llvm-svn: 75640
SCEVZeroExtendExpr ahead of the most expensive analysis. This
speeds up analysis and helps avoid pathologically bad behavior
on the testcase in PR4534.
llvm-svn: 75496
