llvm-6502/lib/CodeGen
Chris Lattner b3ddfc42af add two dag combines:
(C1-X) == C2 --> X == C1-C2
(X+C1) == C2 --> X == C2-C1

This allows us to compile this:

bool %X(int %X) {
        %Y = add int %X, 14
        %Z = setne int %Y, 12345
        ret bool %Z
}

into this:

_X:
        cmpl $12331, 4(%esp)
        setne %al
        movzbl %al, %eax
        andl $1, %eax
        ret

not this:

_X:
        movl $14, %eax
        addl 4(%esp), %eax
        cmpl $12345, %eax
        setne %al
        movzbl %al, %eax
        andl $1, %eax
        ret

Testcase here: Regression/CodeGen/X86/compare-add.ll

nukage of the and coming up next.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@25898 91177308-0d34-0410-b5e6-96231b3b80d8
2006-02-02 06:36:13 +00:00
..
SelectionDAG add two dag combines: 2006-02-02 06:36:13 +00:00
AsmPrinter.cpp Implement smart printing of inline asm strings, handling variants and 2006-02-01 22:41:11 +00:00
BranchFolding.cpp Remove trailing whitespace 2005-04-21 22:36:52 +00:00
DwarfWriter.cpp Using bit size of integers instead of ambiguous "long" et all. 2006-01-27 20:31:25 +00:00
ELFWriter.cpp add these so I can be less naughty 2005-12-28 06:29:02 +00:00
IntrinsicLowering.cpp For PR411: 2006-01-16 21:12:35 +00:00
LiveInterval.cpp Fix LiveInterval::getOverlapingRanges to take things in the right order 2005-10-21 06:41:30 +00:00
LiveIntervalAnalysis.cpp Add explicit #includes of <iostream> 2006-01-22 23:41:00 +00:00
LiveVariables.cpp Add a LiveVariables::VarInfo::dump method 2006-01-04 05:40:30 +00:00
MachineBasicBlock.cpp Remove trailing whitespace 2005-04-21 22:36:52 +00:00
MachineCodeEmitter.cpp mixed-STL programs are big and nasty :( 2005-12-28 02:44:35 +00:00
MachineDebugInfo.cpp Fix build error that is apparently only a warning with some compilers. 2006-01-27 17:31:30 +00:00
MachineFunction.cpp Allow the specification of explicit alignments for constant pool entries. 2006-01-31 22:23:14 +00:00
MachineInstr.cpp Remove trailing whitespace 2005-04-21 22:36:52 +00:00
Makefile Change Library Names Not To Conflict With Others When Installed 2004-10-27 23:18:45 +00:00
Passes.cpp Alkis agrees that that iterative scan allocator isn't going to be worked on 2005-10-24 04:14:30 +00:00
PHIElimination.cpp Add support for targets (like Alpha) that have terminator instructions which 2006-01-04 07:12:21 +00:00
PhysRegTracker.h Improved PhysRegTracker interface. RegAlloc lazily allocates the register tracker using a std::auto_ptr 2004-02-23 06:10:13 +00:00
PrologEpilogInserter.cpp Always compute max align. 2005-11-06 17:43:20 +00:00
RegAllocLinearScan.cpp Add explicit #includes of <iostream> 2006-01-22 23:41:00 +00:00
RegAllocLocal.cpp Add explicit #includes of <iostream> 2006-01-22 23:41:00 +00:00
RegAllocSimple.cpp Add explicit #includes of <iostream> 2006-01-22 23:41:00 +00:00
TwoAddressInstructionPass.cpp Add explicit #includes of <iostream> 2006-01-22 23:41:00 +00:00
UnreachableBlockElim.cpp Remove trailing whitespace 2005-04-21 22:36:52 +00:00
VirtRegMap.cpp Add explicit #includes of <iostream> 2006-01-22 23:41:00 +00:00
VirtRegMap.h Remove trailing whitespace 2005-04-21 22:36:52 +00:00