RPCS3/llvm-mirror
1
0
Fork 0
mirror of https://github.com/RPCS3/llvm-mirror.git synced 2024-10-20 19:42:54 +02:00
Code Issues Projects Releases Wiki Activity

Pull and through and/or/xor. This compiles some bitfield code to:

Browse Source 
mov EAX, DWORD PTR [ESP + 4]
        mov ECX, DWORD PTR [EAX]
        mov EDX, ECX
        add EDX, EDX
        or EDX, ECX
        and EDX, -2147483648
        and ECX, 2147483647
        or EDX, ECX
        mov DWORD PTR [EAX], EDX
        ret

instead of:

        sub ESP, 4
        mov DWORD PTR [ESP], ESI
        mov EAX, DWORD PTR [ESP + 8]
        mov ECX, DWORD PTR [EAX]
        mov EDX, ECX
        add EDX, EDX
        mov ESI, ECX
        and ESI, -2147483648
        and EDX, -2147483648
        or EDX, ESI
        and ECX, 2147483647
        or EDX, ECX
        mov DWORD PTR [EAX], EDX
        mov ESI, DWORD PTR [ESP]
        add ESP, 4
        ret

llvm-svn: 28122
This commit is contained in:
Chris Lattner 2006-05-05 06:10:43 +00:00
parent 02bb78abd3
commit bec98440f4
1 changed files with 6 additions and 4 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

10
lib/CodeGen/SelectionDAG/DAGCombiner.cpp
View File

@ -1069,11 +1069,13 @@ SDOperand DAGCombiner::SimplifyBinOpWithSameOpcodeHands(SDNode *N) {
return DAG.getNode(ISD::TRUNCATE, VT, ORNode);
}
// fold (and (shl/srl/sra x), (shl/srl/sra y)) -> (shl/srl/sra (and x, y))
// fold (or (shl/srl/sra x), (shl/srl/sra y)) -> (shl/srl/sra (or x, y))
// fold (xor (shl/srl/sra x), (shl/srl/sra y)) -> (shl/srl/sra (xor x, y))
// For each of OP in SHL/SRL/SRA/AND...
// fold (and (OP x, z), (OP y, z)) -> (OP (and x, y), z)
// fold (or (OP x, z), (OP y, z)) -> (OP (or x, y), z)
// fold (xor (OP x, z), (OP y, z)) -> (OP (xor x, y), z)
if ((N0.getOpcode() == ISD::SHL || N0.getOpcode() == ISD::SRL ||
N0.getOpcode() == ISD::SRA) &&
N0.getOpcode() == ISD::SRA || N0.getOpcode() == ISD::AND) &&
N0.getOperand(1) == N1.getOperand(1)) {
SDOperand ORNode = DAG.getNode(N->getOpcode(),
N0.getOperand(0).getValueType(),