allows optimization of this:
int %test4(int %A, int %B) {
%a = xor int %A, -1
%c = and int %a, 5 ; 5 = ~c2
%d = xor int %c, -1
ret int %d
}
into this:
int %test4(int %A, int %B) { ; No predecessors!
%c.demorgan = or int %A, -6 ; <int> [#uses=1]
ret int %c.demorgan
}
llvm-svn: 5736
* A & ~A == 0
* A / (2^c) == A >> c if unsigned
* 0 / A == 0
* 1.0 * A == A
* A * (2^c) == A << c
* A ^ ~A == -1
* A | ~A == -1
* 0 % X = 0
* A % (2^c) == A & (c-1) if unsigned
* A - (A & B) == A & ~B
* -1 - A == ~A
llvm-svn: 5587
* Renamed StatisticReporter.h/cpp to Statistic.h/cpp
* Broke constructor to take two const char * arguments instead of one, so
that indendation can be taken care of automatically.
* Sort the list by pass name when printing
* Make sure to print all statistics as a group, instead of randomly when
the statistics dtors are called.
* Updated ProgrammersManual with new semantics.
llvm-svn: 4002
* New ReplaceInstUsesWith function to factor out tons of common code
This needs to be used more in the future still, but it's a good start
* New InsertNewInstBefore to allow multi-instruction replacements
* Change getMaxValue functions to isAllOnesValue function, which doesn't
have to CREATE/lookup a new constant. Also the name is accurate
* Add new isMaxValue, isMinValue, isMaxValueMinusOne, isMinValuePlusOne
functions: This should be moved to Constant* classes eventually
* Implement xor X, ALLONES -> not X
* Fold ALL setcc's of booleans away
* Handle various SetCC's for integers against values at the end of their
ranges, possibly off by one. This implements the setcc-strength-reduce.ll
testcase.
llvm-svn: 3286
- Reenable gep (gep x) -> x
- Make instcombine do dead instruction elimination where it's really
easy. Now visitors don't have to ensure they aren't not processing
dead instructions.
llvm-svn: 3222
* Add new RegisterOpt/RegisterAnalysis templates for registering passes that
are to show up in opt or analyze
* Register Analyses now
* Change optimizations to use RegisterOpt instead of RegisterPass
* Add support for different "PassType's"
* Add new RegisterOpt/RegisterAnalysis templates for registering passes that
are to show up in opt or analyze
* Register Analyses now
* Change optimizations to use RegisterOpt instead of RegisterPass
* Remove getPassName implementations from various subclasses
llvm-svn: 3113
"This testcase caused instcombine to fail because it got the same instruction on
it's worklist more than once (which is ok), but then deleted the instruction.
Since the inst stayed on the worklist, as soon as it came back up to be
processed, bad things happened, and opt asserted."
llvm-svn: 2623
Chris Lattner