[llvm-commits] CVS: llvm/lib/Target/X86/X86ISelPattern.cpp
Chris Lattner
lattner at cs.uiuc.edu
Mon Jan 10 22:19:41 PST 2005
Changes in directory llvm/lib/Target/X86:
X86ISelPattern.cpp updated: 1.30 -> 1.31
---
Log message:
Implement MEMCPY natively in terms of rep movs*
---
Diffs of the changes: (+45 -1)
Index: llvm/lib/Target/X86/X86ISelPattern.cpp
diff -u llvm/lib/Target/X86/X86ISelPattern.cpp:1.30 llvm/lib/Target/X86/X86ISelPattern.cpp:1.31
--- llvm/lib/Target/X86/X86ISelPattern.cpp:1.30 Tue Jan 11 00:14:36 2005
+++ llvm/lib/Target/X86/X86ISelPattern.cpp Tue Jan 11 00:19:26 2005
@@ -50,7 +50,6 @@
computeRegisterProperties();
- setOperationUnsupported(ISD::MEMCPY, MVT::Other);
setOperationUnsupported(ISD::MEMMOVE, MVT::Other);
setOperationUnsupported(ISD::MUL, MVT::i8);
@@ -2088,6 +2087,51 @@
BuildMI(BB, Opcode, 0);
return;
}
+ case ISD::MEMCPY:
+ Select(N.getOperand(0)); // Select the chain.
+ unsigned Align =
+ (unsigned)cast<ConstantSDNode>(Node->getOperand(4))->getValue();
+ if (Align == 0) Align = 1;
+
+ // Turn the byte code into # iterations
+ unsigned CountReg;
+ unsigned Opcode;
+ switch (Align & 3) {
+ case 2: // WORD aligned
+ CountReg = MakeReg(MVT::i32);
+ if (ConstantSDNode *I = dyn_cast<ConstantSDNode>(Node->getOperand(3))) {
+ BuildMI(BB, X86::MOV32ri, 1, CountReg).addImm(I->getValue()/2);
+ } else {
+ unsigned ByteReg = SelectExpr(Node->getOperand(3));
+ BuildMI(BB, X86::SHR32ri, 2, CountReg).addReg(ByteReg).addImm(1);
+ }
+ Opcode = X86::REP_MOVSW;
+ break;
+ case 0: // DWORD aligned
+ CountReg = MakeReg(MVT::i32);
+ if (ConstantSDNode *I = dyn_cast<ConstantSDNode>(Node->getOperand(3))) {
+ BuildMI(BB, X86::MOV32ri, 1, CountReg).addImm(I->getValue()/4);
+ } else {
+ unsigned ByteReg = SelectExpr(Node->getOperand(3));
+ BuildMI(BB, X86::SHR32ri, 2, CountReg).addReg(ByteReg).addImm(2);
+ }
+ Opcode = X86::REP_MOVSD;
+ break;
+ default: // BYTE aligned
+ CountReg = SelectExpr(Node->getOperand(3));
+ Opcode = X86::REP_MOVSB;
+ break;
+ }
+
+ // No matter what the alignment is, we put the source in ESI, the
+ // destination in EDI, and the count in ECX.
+ unsigned TmpReg1 = SelectExpr(Node->getOperand(1));
+ unsigned TmpReg2 = SelectExpr(Node->getOperand(2));
+ BuildMI(BB, X86::MOV32rr, 1, X86::ECX).addReg(CountReg);
+ BuildMI(BB, X86::MOV32rr, 1, X86::EDI).addReg(TmpReg1);
+ BuildMI(BB, X86::MOV32rr, 1, X86::ESI).addReg(TmpReg2);
+ BuildMI(BB, Opcode, 0);
+ return;
}
assert(0 && "Should not be reached!");
}
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