1 //=== HexagonSplitConst32AndConst64.cpp - split CONST32/Const64 into HI/LO ===//
3 // The LLVM Compiler Infrastructure
5 // This file is distributed under the University of Illinois Open Source
6 // License. See LICENSE.TXT for details.
8 //===----------------------------------------------------------------------===//
10 // When the compiler is invoked with no small data, for instance, with the -G0
11 // command line option, then all CONST32_* opcodes should be broken down into
12 // appropriate LO and HI instructions. This splitting is done by this pass.
13 // The only reason this is not done in the DAG lowering itself is that there
14 // is no simple way of getting the register allocator to allot the same hard
15 // register to the result of LO and HI instructions. This pass is always
16 // scheduled after register allocation.
18 //===----------------------------------------------------------------------===//
20 #include "HexagonMachineFunctionInfo.h"
21 #include "HexagonSubtarget.h"
22 #include "HexagonTargetMachine.h"
23 #include "HexagonTargetObjectFile.h"
24 #include "llvm/ADT/Statistic.h"
25 #include "llvm/CodeGen/LatencyPriorityQueue.h"
26 #include "llvm/CodeGen/MachineDominators.h"
27 #include "llvm/CodeGen/MachineFunctionPass.h"
28 #include "llvm/CodeGen/MachineInstrBuilder.h"
29 #include "llvm/CodeGen/MachineLoopInfo.h"
30 #include "llvm/CodeGen/MachineRegisterInfo.h"
31 #include "llvm/CodeGen/Passes.h"
32 #include "llvm/CodeGen/ScheduleDAGInstrs.h"
33 #include "llvm/CodeGen/ScheduleHazardRecognizer.h"
34 #include "llvm/CodeGen/SchedulerRegistry.h"
35 #include "llvm/Support/CommandLine.h"
36 #include "llvm/Support/Compiler.h"
37 #include "llvm/Support/Debug.h"
38 #include "llvm/Support/MathExtras.h"
39 #include "llvm/Target/TargetInstrInfo.h"
40 #include "llvm/Target/TargetMachine.h"
41 #include "llvm/Target/TargetRegisterInfo.h"
46 #define DEBUG_TYPE "xfer"
50 class HexagonSplitConst32AndConst64 : public MachineFunctionPass {
53 HexagonSplitConst32AndConst64() : MachineFunctionPass(ID) {}
55 const char *getPassName() const override {
56 return "Hexagon Split Const32s and Const64s";
58 bool runOnMachineFunction(MachineFunction &Fn) override;
62 char HexagonSplitConst32AndConst64::ID = 0;
65 bool HexagonSplitConst32AndConst64::runOnMachineFunction(MachineFunction &Fn) {
67 const HexagonTargetObjectFile &TLOF =
68 *static_cast<const HexagonTargetObjectFile *>(
69 Fn.getTarget().getObjFileLowering());
70 if (TLOF.IsSmallDataEnabled())
73 const TargetInstrInfo *TII = Fn.getSubtarget().getInstrInfo();
74 const TargetRegisterInfo *TRI = Fn.getSubtarget().getRegisterInfo();
76 // Loop over all of the basic blocks
77 for (MachineFunction::iterator MBBb = Fn.begin(), MBBe = Fn.end();
78 MBBb != MBBe; ++MBBb) {
79 MachineBasicBlock* MBB = MBBb;
80 // Traverse the basic block
81 MachineBasicBlock::iterator MII = MBB->begin();
82 MachineBasicBlock::iterator MIE = MBB->end ();
84 MachineInstr *MI = MII;
85 int Opc = MI->getOpcode();
86 if (Opc == Hexagon::CONST32_Int_Real &&
87 MI->getOperand(1).isBlockAddress()) {
88 int DestReg = MI->getOperand(0).getReg();
89 MachineOperand &Symbol = MI->getOperand (1);
91 BuildMI (*MBB, MII, MI->getDebugLoc(),
92 TII->get(Hexagon::LO), DestReg).addOperand(Symbol);
93 BuildMI (*MBB, MII, MI->getDebugLoc(),
94 TII->get(Hexagon::HI), DestReg).addOperand(Symbol);
95 // MBB->erase returns the iterator to the next instruction, which is the
96 // one we want to process next
97 MII = MBB->erase (MI);
101 else if (Opc == Hexagon::CONST32_Int_Real ||
102 Opc == Hexagon::CONST32_Float_Real) {
103 int DestReg = MI->getOperand(0).getReg();
105 // We have to convert an FP immediate into its corresponding integer
108 if (Opc == Hexagon::CONST32_Float_Real) {
109 APFloat Val = MI->getOperand(1).getFPImm()->getValueAPF();
110 ImmValue = *Val.bitcastToAPInt().getRawData();
113 ImmValue = MI->getOperand(1).getImm();
115 BuildMI(*MBB, MII, MI->getDebugLoc(),
116 TII->get(Hexagon::A2_tfrsi), DestReg).addImm(ImmValue);
117 MII = MBB->erase (MI);
120 else if (Opc == Hexagon::CONST64_Int_Real ||
121 Opc == Hexagon::CONST64_Float_Real) {
122 int DestReg = MI->getOperand(0).getReg();
124 // We have to convert an FP immediate into its corresponding integer
127 if (Opc == Hexagon::CONST64_Float_Real) {
128 APFloat Val = MI->getOperand(1).getFPImm()->getValueAPF();
129 ImmValue = *Val.bitcastToAPInt().getRawData();
132 ImmValue = MI->getOperand(1).getImm();
134 unsigned DestLo = TRI->getSubReg(DestReg, Hexagon::subreg_loreg);
135 unsigned DestHi = TRI->getSubReg(DestReg, Hexagon::subreg_hireg);
137 int32_t LowWord = (ImmValue & 0xFFFFFFFF);
138 int32_t HighWord = (ImmValue >> 32) & 0xFFFFFFFF;
140 BuildMI(*MBB, MII, MI->getDebugLoc(),
141 TII->get(Hexagon::A2_tfrsi), DestLo).addImm(LowWord);
142 BuildMI (*MBB, MII, MI->getDebugLoc(),
143 TII->get(Hexagon::A2_tfrsi), DestHi).addImm(HighWord);
144 MII = MBB->erase (MI);
156 //===----------------------------------------------------------------------===//
157 // Public Constructor Functions
158 //===----------------------------------------------------------------------===//
161 llvm::createHexagonSplitConst32AndConst64() {
162 return new HexagonSplitConst32AndConst64();