diff options
| -rw-r--r-- | llvm/lib/Target/ARM/ARMBaseInstrInfo.cpp | 1 | ||||
| -rw-r--r-- | llvm/lib/Target/ARM/ARMISelLowering.cpp | 25 | ||||
| -rw-r--r-- | llvm/lib/Target/ARM/ARMISelLowering.h | 1 | ||||
| -rw-r--r-- | llvm/lib/Target/ARM/ARMInstrInfo.td | 1 | ||||
| -rw-r--r-- | llvm/lib/Target/ARM/ARMInstrThumb.td | 6 | ||||
| -rw-r--r-- | llvm/test/CodeGen/Thumb/cmp-and-fold.ll | 10 |
6 files changed, 36 insertions, 8 deletions
diff --git a/llvm/lib/Target/ARM/ARMBaseInstrInfo.cpp b/llvm/lib/Target/ARM/ARMBaseInstrInfo.cpp index 222aa85856a..7b5e45f0ba2 100644 --- a/llvm/lib/Target/ARM/ARMBaseInstrInfo.cpp +++ b/llvm/lib/Target/ARM/ARMBaseInstrInfo.cpp @@ -2298,6 +2298,7 @@ static const AddSubFlagsOpcodePair AddSubFlagsOpcodeMap[] = { {ARM::tSUBSrr, ARM::tSUBrr}, {ARM::tSBCS, ARM::tSBC}, {ARM::tRSBS, ARM::tRSB}, + {ARM::tLSLSri, ARM::tLSLri}, {ARM::t2ADDSri, ARM::t2ADDri}, {ARM::t2ADDSrr, ARM::t2ADDrr}, diff --git a/llvm/lib/Target/ARM/ARMISelLowering.cpp b/llvm/lib/Target/ARM/ARMISelLowering.cpp index a87770125fd..e372bdb4f58 100644 --- a/llvm/lib/Target/ARM/ARMISelLowering.cpp +++ b/llvm/lib/Target/ARM/ARMISelLowering.cpp @@ -1490,6 +1490,7 @@ const char *ARMTargetLowering::getTargetNodeName(unsigned Opcode) const { case ARMISD::ADDE: return "ARMISD::ADDE"; case ARMISD::SUBC: return "ARMISD::SUBC"; case ARMISD::SUBE: return "ARMISD::SUBE"; + case ARMISD::LSLS: return "ARMISD::LSLS"; case ARMISD::VMOVRRD: return "ARMISD::VMOVRRD"; case ARMISD::VMOVDRR: return "ARMISD::VMOVDRR"; @@ -4110,6 +4111,30 @@ SDValue ARMTargetLowering::getARMCmp(SDValue LHS, SDValue RHS, ISD::CondCode CC, } } } + + // The specific comparison "(x<<c) > 0x80000000U" can be optimized to a + // single "lsls x, c+1". The shift sets the "C" and "Z" flags the same + // way a cmp would. + // FIXME: Add support for ARM/Thumb2; this would need isel patterns, and + // some tweaks to the heuristics for the previous and->shift transform. + // FIXME: Optimize cases where the LHS isn't a shift. + if (Subtarget->isThumb1Only() && LHS->getOpcode() == ISD::SHL && + isa<ConstantSDNode>(RHS) && + cast<ConstantSDNode>(RHS)->getZExtValue() == 0x80000000U && + CC == ISD::SETUGT && isa<ConstantSDNode>(LHS.getOperand(1)) && + cast<ConstantSDNode>(LHS.getOperand(1))->getZExtValue() < 31) { + unsigned ShiftAmt = + cast<ConstantSDNode>(LHS.getOperand(1))->getZExtValue() + 1; + SDValue Shift = DAG.getNode(ARMISD::LSLS, dl, + DAG.getVTList(MVT::i32, MVT::i32), + LHS.getOperand(0), + DAG.getConstant(ShiftAmt, dl, MVT::i32)); + SDValue Chain = DAG.getCopyToReg(DAG.getEntryNode(), dl, ARM::CPSR, + Shift.getValue(1), SDValue()); + ARMcc = DAG.getConstant(ARMCC::HI, dl, MVT::i32); + return Chain.getValue(1); + } + ARMCC::CondCodes CondCode = IntCCToARMCC(CC); // If the RHS is a constant zero then the V (overflow) flag will never be diff --git a/llvm/lib/Target/ARM/ARMISelLowering.h b/llvm/lib/Target/ARM/ARMISelLowering.h index f584f9cfb9c..ae10bcd6cf0 100644 --- a/llvm/lib/Target/ARM/ARMISelLowering.h +++ b/llvm/lib/Target/ARM/ARMISelLowering.h @@ -103,6 +103,7 @@ class VectorType; ADDE, // Add using carry SUBC, // Sub with carry SUBE, // Sub using carry + LSLS, // Shift left producing carry VMOVRRD, // double to two gprs. VMOVDRR, // Two gprs to double. diff --git a/llvm/lib/Target/ARM/ARMInstrInfo.td b/llvm/lib/Target/ARM/ARMInstrInfo.td index 0e3a9af56b1..7783bedc210 100644 --- a/llvm/lib/Target/ARM/ARMInstrInfo.td +++ b/llvm/lib/Target/ARM/ARMInstrInfo.td @@ -194,6 +194,7 @@ def ARMrrx : SDNode<"ARMISD::RRX" , SDTIntUnaryOp, [SDNPInGlue ]>; def ARMaddc : SDNode<"ARMISD::ADDC", SDTBinaryArithWithFlags, [SDNPCommutative]>; def ARMsubc : SDNode<"ARMISD::SUBC", SDTBinaryArithWithFlags>; +def ARMlsls : SDNode<"ARMISD::LSLS", SDTBinaryArithWithFlags>; def ARMadde : SDNode<"ARMISD::ADDE", SDTBinaryArithWithFlagsInOut>; def ARMsube : SDNode<"ARMISD::SUBE", SDTBinaryArithWithFlagsInOut>; diff --git a/llvm/lib/Target/ARM/ARMInstrThumb.td b/llvm/lib/Target/ARM/ARMInstrThumb.td index cfeb13c6acb..b3f4b34c73a 100644 --- a/llvm/lib/Target/ARM/ARMInstrThumb.td +++ b/llvm/lib/Target/ARM/ARMInstrThumb.td @@ -1362,6 +1362,12 @@ let hasPostISelHook = 1, Defs = [CPSR] in { [(set tGPR:$Rd, CPSR, (ARMsubc 0, tGPR:$Rn))]>, Requires<[IsThumb1Only]>, Sched<[WriteALU]>; + + def tLSLSri : tPseudoInst<(outs tGPR:$Rd), (ins tGPR:$Rn, imm0_31:$imm5), + 2, IIC_iALUr, + [(set tGPR:$Rd, CPSR, (ARMlsls tGPR:$Rn, imm0_31:$imm5))]>, + Requires<[IsThumb1Only]>, + Sched<[WriteALU]>; } diff --git a/llvm/test/CodeGen/Thumb/cmp-and-fold.ll b/llvm/test/CodeGen/Thumb/cmp-and-fold.ll index ba2e4fec9ac..44c873a5fe2 100644 --- a/llvm/test/CodeGen/Thumb/cmp-and-fold.ll +++ b/llvm/test/CodeGen/Thumb/cmp-and-fold.ll @@ -31,10 +31,7 @@ define void @test2(i32 %x, void ()* %f) { ; CHECK: @ %bb.0: @ %entry ; CHECK-NEXT: .save {r7, lr} ; CHECK-NEXT: push {r7, lr} -; CHECK-NEXT: movs r2, #1 -; CHECK-NEXT: lsls r2, r2, #31 -; CHECK-NEXT: lsls r0, r0, #7 -; CHECK-NEXT: cmp r0, r2 +; CHECK-NEXT: lsls r0, r0, #8 ; CHECK-NEXT: bhi .LBB1_2 ; CHECK-NEXT: @ %bb.1: @ %if.then ; CHECK-NEXT: blx r1 @@ -58,10 +55,7 @@ define void @test3(i32 %x, void ()* %f) { ; CHECK: @ %bb.0: @ %entry ; CHECK-NEXT: .save {r7, lr} ; CHECK-NEXT: push {r7, lr} -; CHECK-NEXT: movs r2, #1 -; CHECK-NEXT: lsls r2, r2, #31 -; CHECK-NEXT: lsls r0, r0, #2 -; CHECK-NEXT: cmp r0, r2 +; CHECK-NEXT: lsls r0, r0, #3 ; CHECK-NEXT: bhi .LBB2_2 ; CHECK-NEXT: @ %bb.1: @ %if.then ; CHECK-NEXT: blx r1 |
