From 6b8d2026ba0b60a317fa239eacbcaeff5f2270f0 Mon Sep 17 00:00:00 2001 From: Jyotsna Verma Date: Tue, 12 Feb 2013 16:06:23 +0000 Subject: [PATCH] Hexagon: Add support to generate predicated absolute addressing mode instructions. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@174973 91177308-0d34-0410-b5e6-96231b3b80d8 --- lib/Target/Hexagon/HexagonInstrInfo.cpp | 143 +++++++++++++++++--- test/CodeGen/Hexagon/pred-absolute-store.ll | 19 +++ 2 files changed, 142 insertions(+), 20 deletions(-) create mode 100644 test/CodeGen/Hexagon/pred-absolute-store.ll diff --git a/lib/Target/Hexagon/HexagonInstrInfo.cpp b/lib/Target/Hexagon/HexagonInstrInfo.cpp index ee37deab8d8..10055533a97 100644 --- a/lib/Target/Hexagon/HexagonInstrInfo.cpp +++ b/lib/Target/Hexagon/HexagonInstrInfo.cpp @@ -2237,38 +2237,141 @@ PredicateInstruction(MachineInstr *MI, assert (isPredicable(MI) && "Expected predicable instruction"); bool invertJump = (!Cond.empty() && Cond[0].isImm() && (Cond[0].getImm() == 0)); + + // This will change MI's opcode to its predicate version. + // However, its operand list is still the old one, i.e. the + // non-predicate one. MI->setDesc(get(getMatchingCondBranchOpcode(Opc, invertJump))); - // - // This assumes that the predicate is always the first operand - // in the set of inputs. - // - MI->addOperand(MI->getOperand(MI->getNumOperands()-1)); - int oper; - for (oper = MI->getNumOperands() - 3; oper >= 0; --oper) { - MachineOperand MO = MI->getOperand(oper); - if ((MO.isReg() && !MO.isUse() && !MO.isImplicit())) { - break; - } - if (MO.isReg()) { - MI->getOperand(oper+1).ChangeToRegister(MO.getReg(), MO.isDef(), - MO.isImplicit(), MO.isKill(), - MO.isDead(), MO.isUndef(), - MO.isDebug()); - } else if (MO.isImm()) { - MI->getOperand(oper+1).ChangeToImmediate(MO.getImm()); - } else { - llvm_unreachable("Unexpected operand type"); + int oper = -1; + unsigned int GAIdx = 0; + + // Indicates whether the current MI has a GlobalAddress operand + bool hasGAOpnd = false; + std::vector tmpOpnds; + + // Indicates whether we need to shift operands to right. + bool needShift = true; + + // The predicate is ALWAYS the FIRST input operand !!! + if (MI->getNumOperands() == 0) { + // The non-predicate version of MI does not take any operands, + // i.e. no outs and no ins. In this condition, the predicate + // operand will be directly placed at Operands[0]. No operand + // shift is needed. + // Example: BARRIER + needShift = false; + oper = -1; + } + else if ( MI->getOperand(MI->getNumOperands()-1).isReg() + && MI->getOperand(MI->getNumOperands()-1).isDef() + && !MI->getOperand(MI->getNumOperands()-1).isImplicit()) { + // The non-predicate version of MI does not have any input operands. + // In this condition, we extend the length of Operands[] by one and + // copy the original last operand to the newly allocated slot. + // At this moment, it is just a place holder. Later, we will put + // predicate operand directly into it. No operand shift is needed. + // Example: r0=BARRIER (this is a faked insn used here for illustration) + MI->addOperand(MI->getOperand(MI->getNumOperands()-1)); + needShift = false; + oper = MI->getNumOperands() - 2; + } + else { + // We need to right shift all input operands by one. Duplicate the + // last operand into the newly allocated slot. + MI->addOperand(MI->getOperand(MI->getNumOperands()-1)); + } + + if (needShift) + { + // Operands[ MI->getNumOperands() - 2 ] has been copied into + // Operands[ MI->getNumOperands() - 1 ], so we start from + // Operands[ MI->getNumOperands() - 3 ]. + // oper is a signed int. + // It is ok if "MI->getNumOperands()-3" is -3, -2, or -1. + for (oper = MI->getNumOperands() - 3; oper >= 0; --oper) + { + MachineOperand &MO = MI->getOperand(oper); + + // Opnd[0] Opnd[1] Opnd[2] Opnd[3] Opnd[4] Opnd[5] Opnd[6] Opnd[7] + // + // /\~ + // /||\~ + // || + // Predicate Operand here + if (MO.isReg() && !MO.isUse() && !MO.isImplicit()) { + break; + } + if (MO.isReg()) { + MI->getOperand(oper+1).ChangeToRegister(MO.getReg(), MO.isDef(), + MO.isImplicit(), MO.isKill(), + MO.isDead(), MO.isUndef(), + MO.isDebug()); + } + else if (MO.isImm()) { + MI->getOperand(oper+1).ChangeToImmediate(MO.getImm()); + } + else if (MO.isGlobal()) { + // MI can not have more than one GlobalAddress operand. + assert(hasGAOpnd == false && "MI can only have one GlobalAddress opnd"); + + // There is no member function called "ChangeToGlobalAddress" in the + // MachineOperand class (not like "ChangeToRegister" and + // "ChangeToImmediate"). So we have to remove them from Operands[] list + // first, and then add them back after we have inserted the predicate + // operand. tmpOpnds[] is to remember these operands before we remove + // them. + tmpOpnds.push_back(MO); + + // Operands[oper] is a GlobalAddress operand; + // Operands[oper+1] has been copied into Operands[oper+2]; + hasGAOpnd = true; + GAIdx = oper; + continue; + } + else { + assert(false && "Unexpected operand type"); + } } } int regPos = invertJump ? 1 : 0; MachineOperand PredMO = Cond[regPos]; + + // [oper] now points to the last explicit Def. Predicate operand must be + // located at [oper+1]. See diagram above. + // This assumes that the predicate is always the first operand, + // i.e. Operands[0+numResults], in the set of inputs + // It is better to have an assert here to check this. But I don't know how + // to write this assert because findFirstPredOperandIdx() would return -1 + if (oper < -1) oper = -1; MI->getOperand(oper+1).ChangeToRegister(PredMO.getReg(), PredMO.isDef(), PredMO.isImplicit(), PredMO.isKill(), PredMO.isDead(), PredMO.isUndef(), PredMO.isDebug()); + if (hasGAOpnd) + { + unsigned int i; + + // Operands[GAIdx] is the original GlobalAddress operand, which is + // already copied into tmpOpnds[0]. + // Operands[GAIdx] now stores a copy of Operands[GAIdx-1] + // Operands[GAIdx+1] has already been copied into Operands[GAIdx+2], + // so we start from [GAIdx+2] + for (i = GAIdx + 2; i < MI->getNumOperands(); ++i) + tmpOpnds.push_back(MI->getOperand(i)); + + // Remove all operands in range [ (GAIdx+1) ... (MI->getNumOperands()-1) ] + // It is very important that we always remove from the end of Operands[] + // MI->getNumOperands() is at least 2 if program goes to here. + for (i = MI->getNumOperands() - 1; i > GAIdx; --i) + MI->RemoveOperand(i); + + for (i = 0; i < tmpOpnds.size(); ++i) + MI->addOperand(tmpOpnds[i]); + } + return true; } diff --git a/test/CodeGen/Hexagon/pred-absolute-store.ll b/test/CodeGen/Hexagon/pred-absolute-store.ll new file mode 100644 index 00000000000..b1b09f414a5 --- /dev/null +++ b/test/CodeGen/Hexagon/pred-absolute-store.ll @@ -0,0 +1,19 @@ +; RUN: llc -march=hexagon -mcpu=hexagonv4 < %s | FileCheck %s +; Check that we are able to predicate instructions with abosolute +; addressing mode. + +; CHECK: if{{ *}}(p{{[0-3]+}}){{ *}}memw(##gvar){{ *}}={{ *}}r{{[0-9]+}} + +@gvar = external global i32 +define i32 @test2(i32 %a, i32 %b) nounwind { +entry: + %cmp = icmp eq i32 %a, %b + br i1 %cmp, label %if.then, label %if.end + +if.then: + store i32 %a, i32* @gvar, align 4 + br label %if.end + +if.end: + ret i32 %b +} -- 2.34.1