1 //===- PPCRegisterInfo.cpp - PowerPC Register Information -------*- C++ -*-===//
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 // This file contains the PowerPC implementation of the TargetRegisterInfo
13 //===----------------------------------------------------------------------===//
15 #define DEBUG_TYPE "reginfo"
17 #include "PPCInstrBuilder.h"
18 #include "PPCMachineFunctionInfo.h"
19 #include "PPCRegisterInfo.h"
20 #include "PPCFrameLowering.h"
21 #include "PPCSubtarget.h"
22 #include "llvm/CallingConv.h"
23 #include "llvm/Constants.h"
24 #include "llvm/Function.h"
25 #include "llvm/Type.h"
26 #include "llvm/CodeGen/ValueTypes.h"
27 #include "llvm/CodeGen/MachineInstrBuilder.h"
28 #include "llvm/CodeGen/MachineModuleInfo.h"
29 #include "llvm/CodeGen/MachineFunction.h"
30 #include "llvm/CodeGen/MachineFrameInfo.h"
31 #include "llvm/CodeGen/MachineLocation.h"
32 #include "llvm/CodeGen/MachineRegisterInfo.h"
33 #include "llvm/CodeGen/RegisterScavenging.h"
34 #include "llvm/Target/TargetFrameLowering.h"
35 #include "llvm/Target/TargetInstrInfo.h"
36 #include "llvm/Target/TargetMachine.h"
37 #include "llvm/Target/TargetOptions.h"
38 #include "llvm/Support/CommandLine.h"
39 #include "llvm/Support/Debug.h"
40 #include "llvm/Support/ErrorHandling.h"
41 #include "llvm/Support/MathExtras.h"
42 #include "llvm/Support/raw_ostream.h"
43 #include "llvm/ADT/BitVector.h"
44 #include "llvm/ADT/STLExtras.h"
47 // FIXME (64-bit): Eventually enable by default.
49 cl::opt<bool> EnablePPC32RS("enable-ppc32-regscavenger",
51 cl::desc("Enable PPC32 register scavenger"),
53 cl::opt<bool> EnablePPC64RS("enable-ppc64-regscavenger",
55 cl::desc("Enable PPC64 register scavenger"),
61 // FIXME (64-bit): Should be inlined.
63 PPCRegisterInfo::requiresRegisterScavenging(const MachineFunction &) const {
64 return ((EnablePPC32RS && !Subtarget.isPPC64()) ||
65 (EnablePPC64RS && Subtarget.isPPC64()));
68 /// getRegisterNumbering - Given the enum value for some register, e.g.
69 /// PPC::F14, return the number that it corresponds to (e.g. 14).
70 unsigned PPCRegisterInfo::getRegisterNumbering(unsigned RegEnum) {
74 case R0 : case X0 : case F0 : case V0 : case CR0: case CR0LT: return 0;
75 case R1 : case X1 : case F1 : case V1 : case CR1: case CR0GT: return 1;
76 case R2 : case X2 : case F2 : case V2 : case CR2: case CR0EQ: return 2;
77 case R3 : case X3 : case F3 : case V3 : case CR3: case CR0UN: return 3;
78 case R4 : case X4 : case F4 : case V4 : case CR4: case CR1LT: return 4;
79 case R5 : case X5 : case F5 : case V5 : case CR5: case CR1GT: return 5;
80 case R6 : case X6 : case F6 : case V6 : case CR6: case CR1EQ: return 6;
81 case R7 : case X7 : case F7 : case V7 : case CR7: case CR1UN: return 7;
82 case R8 : case X8 : case F8 : case V8 : case CR2LT: return 8;
83 case R9 : case X9 : case F9 : case V9 : case CR2GT: return 9;
84 case R10: case X10: case F10: case V10: case CR2EQ: return 10;
85 case R11: case X11: case F11: case V11: case CR2UN: return 11;
86 case R12: case X12: case F12: case V12: case CR3LT: return 12;
87 case R13: case X13: case F13: case V13: case CR3GT: return 13;
88 case R14: case X14: case F14: case V14: case CR3EQ: return 14;
89 case R15: case X15: case F15: case V15: case CR3UN: return 15;
90 case R16: case X16: case F16: case V16: case CR4LT: return 16;
91 case R17: case X17: case F17: case V17: case CR4GT: return 17;
92 case R18: case X18: case F18: case V18: case CR4EQ: return 18;
93 case R19: case X19: case F19: case V19: case CR4UN: return 19;
94 case R20: case X20: case F20: case V20: case CR5LT: return 20;
95 case R21: case X21: case F21: case V21: case CR5GT: return 21;
96 case R22: case X22: case F22: case V22: case CR5EQ: return 22;
97 case R23: case X23: case F23: case V23: case CR5UN: return 23;
98 case R24: case X24: case F24: case V24: case CR6LT: return 24;
99 case R25: case X25: case F25: case V25: case CR6GT: return 25;
100 case R26: case X26: case F26: case V26: case CR6EQ: return 26;
101 case R27: case X27: case F27: case V27: case CR6UN: return 27;
102 case R28: case X28: case F28: case V28: case CR7LT: return 28;
103 case R29: case X29: case F29: case V29: case CR7GT: return 29;
104 case R30: case X30: case F30: case V30: case CR7EQ: return 30;
105 case R31: case X31: case F31: case V31: case CR7UN: return 31;
107 llvm_unreachable("Unhandled reg in PPCRegisterInfo::getRegisterNumbering!");
111 PPCRegisterInfo::PPCRegisterInfo(const PPCSubtarget &ST,
112 const TargetInstrInfo &tii)
113 : PPCGenRegisterInfo(PPC::ADJCALLSTACKDOWN, PPC::ADJCALLSTACKUP),
114 Subtarget(ST), TII(tii) {
115 ImmToIdxMap[PPC::LD] = PPC::LDX; ImmToIdxMap[PPC::STD] = PPC::STDX;
116 ImmToIdxMap[PPC::LBZ] = PPC::LBZX; ImmToIdxMap[PPC::STB] = PPC::STBX;
117 ImmToIdxMap[PPC::LHZ] = PPC::LHZX; ImmToIdxMap[PPC::LHA] = PPC::LHAX;
118 ImmToIdxMap[PPC::LWZ] = PPC::LWZX; ImmToIdxMap[PPC::LWA] = PPC::LWAX;
119 ImmToIdxMap[PPC::LFS] = PPC::LFSX; ImmToIdxMap[PPC::LFD] = PPC::LFDX;
120 ImmToIdxMap[PPC::STH] = PPC::STHX; ImmToIdxMap[PPC::STW] = PPC::STWX;
121 ImmToIdxMap[PPC::STFS] = PPC::STFSX; ImmToIdxMap[PPC::STFD] = PPC::STFDX;
122 ImmToIdxMap[PPC::ADDI] = PPC::ADD4;
125 ImmToIdxMap[PPC::LHA8] = PPC::LHAX8; ImmToIdxMap[PPC::LBZ8] = PPC::LBZX8;
126 ImmToIdxMap[PPC::LHZ8] = PPC::LHZX8; ImmToIdxMap[PPC::LWZ8] = PPC::LWZX8;
127 ImmToIdxMap[PPC::STB8] = PPC::STBX8; ImmToIdxMap[PPC::STH8] = PPC::STHX8;
128 ImmToIdxMap[PPC::STW8] = PPC::STWX8; ImmToIdxMap[PPC::STDU] = PPC::STDUX;
129 ImmToIdxMap[PPC::ADDI8] = PPC::ADD8; ImmToIdxMap[PPC::STD_32] = PPC::STDX_32;
132 /// getPointerRegClass - Return the register class to use to hold pointers.
133 /// This is used for addressing modes.
134 const TargetRegisterClass *
135 PPCRegisterInfo::getPointerRegClass(unsigned Kind) const {
136 if (Subtarget.isPPC64())
137 return &PPC::G8RCRegClass;
138 return &PPC::GPRCRegClass;
142 PPCRegisterInfo::getCalleeSavedRegs(const MachineFunction *MF) const {
143 // 32-bit Darwin calling convention.
144 static const unsigned Darwin32_CalleeSavedRegs[] = {
145 PPC::R13, PPC::R14, PPC::R15,
146 PPC::R16, PPC::R17, PPC::R18, PPC::R19,
147 PPC::R20, PPC::R21, PPC::R22, PPC::R23,
148 PPC::R24, PPC::R25, PPC::R26, PPC::R27,
149 PPC::R28, PPC::R29, PPC::R30, PPC::R31,
151 PPC::F14, PPC::F15, PPC::F16, PPC::F17,
152 PPC::F18, PPC::F19, PPC::F20, PPC::F21,
153 PPC::F22, PPC::F23, PPC::F24, PPC::F25,
154 PPC::F26, PPC::F27, PPC::F28, PPC::F29,
157 PPC::CR2, PPC::CR3, PPC::CR4,
158 PPC::V20, PPC::V21, PPC::V22, PPC::V23,
159 PPC::V24, PPC::V25, PPC::V26, PPC::V27,
160 PPC::V28, PPC::V29, PPC::V30, PPC::V31,
162 PPC::CR2LT, PPC::CR2GT, PPC::CR2EQ, PPC::CR2UN,
163 PPC::CR3LT, PPC::CR3GT, PPC::CR3EQ, PPC::CR3UN,
164 PPC::CR4LT, PPC::CR4GT, PPC::CR4EQ, PPC::CR4UN,
169 // 32-bit SVR4 calling convention.
170 static const unsigned SVR4_CalleeSavedRegs[] = {
172 PPC::R16, PPC::R17, PPC::R18, PPC::R19,
173 PPC::R20, PPC::R21, PPC::R22, PPC::R23,
174 PPC::R24, PPC::R25, PPC::R26, PPC::R27,
175 PPC::R28, PPC::R29, PPC::R30, PPC::R31,
177 PPC::F14, PPC::F15, PPC::F16, PPC::F17,
178 PPC::F18, PPC::F19, PPC::F20, PPC::F21,
179 PPC::F22, PPC::F23, PPC::F24, PPC::F25,
180 PPC::F26, PPC::F27, PPC::F28, PPC::F29,
183 PPC::CR2, PPC::CR3, PPC::CR4,
187 PPC::V20, PPC::V21, PPC::V22, PPC::V23,
188 PPC::V24, PPC::V25, PPC::V26, PPC::V27,
189 PPC::V28, PPC::V29, PPC::V30, PPC::V31,
191 PPC::CR2LT, PPC::CR2GT, PPC::CR2EQ, PPC::CR2UN,
192 PPC::CR3LT, PPC::CR3GT, PPC::CR3EQ, PPC::CR3UN,
193 PPC::CR4LT, PPC::CR4GT, PPC::CR4EQ, PPC::CR4UN,
197 // 64-bit Darwin calling convention.
198 static const unsigned Darwin64_CalleeSavedRegs[] = {
200 PPC::X16, PPC::X17, PPC::X18, PPC::X19,
201 PPC::X20, PPC::X21, PPC::X22, PPC::X23,
202 PPC::X24, PPC::X25, PPC::X26, PPC::X27,
203 PPC::X28, PPC::X29, PPC::X30, PPC::X31,
205 PPC::F14, PPC::F15, PPC::F16, PPC::F17,
206 PPC::F18, PPC::F19, PPC::F20, PPC::F21,
207 PPC::F22, PPC::F23, PPC::F24, PPC::F25,
208 PPC::F26, PPC::F27, PPC::F28, PPC::F29,
211 PPC::CR2, PPC::CR3, PPC::CR4,
212 PPC::V20, PPC::V21, PPC::V22, PPC::V23,
213 PPC::V24, PPC::V25, PPC::V26, PPC::V27,
214 PPC::V28, PPC::V29, PPC::V30, PPC::V31,
216 PPC::CR2LT, PPC::CR2GT, PPC::CR2EQ, PPC::CR2UN,
217 PPC::CR3LT, PPC::CR3GT, PPC::CR3EQ, PPC::CR3UN,
218 PPC::CR4LT, PPC::CR4GT, PPC::CR4EQ, PPC::CR4UN,
223 // 64-bit SVR4 calling convention.
224 static const unsigned SVR4_64_CalleeSavedRegs[] = {
226 PPC::X16, PPC::X17, PPC::X18, PPC::X19,
227 PPC::X20, PPC::X21, PPC::X22, PPC::X23,
228 PPC::X24, PPC::X25, PPC::X26, PPC::X27,
229 PPC::X28, PPC::X29, PPC::X30, PPC::X31,
231 PPC::F14, PPC::F15, PPC::F16, PPC::F17,
232 PPC::F18, PPC::F19, PPC::F20, PPC::F21,
233 PPC::F22, PPC::F23, PPC::F24, PPC::F25,
234 PPC::F26, PPC::F27, PPC::F28, PPC::F29,
237 PPC::CR2, PPC::CR3, PPC::CR4,
241 PPC::V20, PPC::V21, PPC::V22, PPC::V23,
242 PPC::V24, PPC::V25, PPC::V26, PPC::V27,
243 PPC::V28, PPC::V29, PPC::V30, PPC::V31,
245 PPC::CR2LT, PPC::CR2GT, PPC::CR2EQ, PPC::CR2UN,
246 PPC::CR3LT, PPC::CR3GT, PPC::CR3EQ, PPC::CR3UN,
247 PPC::CR4LT, PPC::CR4GT, PPC::CR4EQ, PPC::CR4UN,
252 if (Subtarget.isDarwinABI())
253 return Subtarget.isPPC64() ? Darwin64_CalleeSavedRegs :
254 Darwin32_CalleeSavedRegs;
256 return Subtarget.isPPC64() ? SVR4_64_CalleeSavedRegs : SVR4_CalleeSavedRegs;
259 BitVector PPCRegisterInfo::getReservedRegs(const MachineFunction &MF) const {
260 BitVector Reserved(getNumRegs());
261 const PPCFrameLowering *PPCFI =
262 static_cast<const PPCFrameLowering*>(MF.getTarget().getFrameLowering());
264 Reserved.set(PPC::R0);
265 Reserved.set(PPC::R1);
266 Reserved.set(PPC::LR);
267 Reserved.set(PPC::LR8);
268 Reserved.set(PPC::RM);
270 // The SVR4 ABI reserves r2 and r13
271 if (Subtarget.isSVR4ABI()) {
272 Reserved.set(PPC::R2); // System-reserved register
273 Reserved.set(PPC::R13); // Small Data Area pointer register
275 // Reserve R2 on Darwin to hack around the problem of save/restore of CR
276 // when the stack frame is too big to address directly; we need two regs.
278 if (Subtarget.isDarwinABI()) {
279 Reserved.set(PPC::R2);
282 // On PPC64, r13 is the thread pointer. Never allocate this register.
283 // Note that this is over conservative, as it also prevents allocation of R31
284 // when the FP is not needed.
285 if (Subtarget.isPPC64()) {
286 Reserved.set(PPC::R13);
287 Reserved.set(PPC::R31);
289 if (!requiresRegisterScavenging(MF))
290 Reserved.set(PPC::R0); // FIXME (64-bit): Remove
292 Reserved.set(PPC::X0);
293 Reserved.set(PPC::X1);
294 Reserved.set(PPC::X13);
295 Reserved.set(PPC::X31);
297 // The 64-bit SVR4 ABI reserves r2 for the TOC pointer.
298 if (Subtarget.isSVR4ABI()) {
299 Reserved.set(PPC::X2);
301 // Reserve R2 on Darwin to hack around the problem of save/restore of CR
302 // when the stack frame is too big to address directly; we need two regs.
304 if (Subtarget.isDarwinABI()) {
305 Reserved.set(PPC::X2);
309 if (PPCFI->needsFP(MF))
310 Reserved.set(PPC::R31);
315 //===----------------------------------------------------------------------===//
316 // Stack Frame Processing methods
317 //===----------------------------------------------------------------------===//
319 void PPCRegisterInfo::
320 eliminateCallFramePseudoInstr(MachineFunction &MF, MachineBasicBlock &MBB,
321 MachineBasicBlock::iterator I) const {
322 if (GuaranteedTailCallOpt && I->getOpcode() == PPC::ADJCALLSTACKUP) {
323 // Add (actually subtract) back the amount the callee popped on return.
324 if (int CalleeAmt = I->getOperand(1).getImm()) {
325 bool is64Bit = Subtarget.isPPC64();
327 unsigned StackReg = is64Bit ? PPC::X1 : PPC::R1;
328 unsigned TmpReg = is64Bit ? PPC::X0 : PPC::R0;
329 unsigned ADDIInstr = is64Bit ? PPC::ADDI8 : PPC::ADDI;
330 unsigned ADDInstr = is64Bit ? PPC::ADD8 : PPC::ADD4;
331 unsigned LISInstr = is64Bit ? PPC::LIS8 : PPC::LIS;
332 unsigned ORIInstr = is64Bit ? PPC::ORI8 : PPC::ORI;
333 MachineInstr *MI = I;
334 DebugLoc dl = MI->getDebugLoc();
336 if (isInt<16>(CalleeAmt)) {
337 BuildMI(MBB, I, dl, TII.get(ADDIInstr), StackReg).addReg(StackReg).
340 MachineBasicBlock::iterator MBBI = I;
341 BuildMI(MBB, MBBI, dl, TII.get(LISInstr), TmpReg)
342 .addImm(CalleeAmt >> 16);
343 BuildMI(MBB, MBBI, dl, TII.get(ORIInstr), TmpReg)
344 .addReg(TmpReg, RegState::Kill)
345 .addImm(CalleeAmt & 0xFFFF);
346 BuildMI(MBB, MBBI, dl, TII.get(ADDInstr))
353 // Simply discard ADJCALLSTACKDOWN, ADJCALLSTACKUP instructions.
357 /// findScratchRegister - Find a 'free' PPC register. Try for a call-clobbered
358 /// register first and then a spilled callee-saved register if that fails.
360 unsigned findScratchRegister(MachineBasicBlock::iterator II, RegScavenger *RS,
361 const TargetRegisterClass *RC, int SPAdj) {
362 assert(RS && "Register scavenging must be on");
363 unsigned Reg = RS->FindUnusedReg(RC);
364 // FIXME: move ARM callee-saved reg scan to target independent code, then
365 // search for already spilled CS register here.
367 Reg = RS->scavengeRegister(RC, II, SPAdj);
371 /// lowerDynamicAlloc - Generate the code for allocating an object in the
372 /// current frame. The sequence of code with be in the general form
374 /// addi R0, SP, \#frameSize ; get the address of the previous frame
375 /// stwxu R0, SP, Rnegsize ; add and update the SP with the negated size
376 /// addi Rnew, SP, \#maxCalFrameSize ; get the top of the allocation
378 void PPCRegisterInfo::lowerDynamicAlloc(MachineBasicBlock::iterator II,
379 int SPAdj, RegScavenger *RS) const {
380 // Get the instruction.
381 MachineInstr &MI = *II;
382 // Get the instruction's basic block.
383 MachineBasicBlock &MBB = *MI.getParent();
384 // Get the basic block's function.
385 MachineFunction &MF = *MBB.getParent();
386 // Get the frame info.
387 MachineFrameInfo *MFI = MF.getFrameInfo();
388 // Determine whether 64-bit pointers are used.
389 bool LP64 = Subtarget.isPPC64();
390 DebugLoc dl = MI.getDebugLoc();
392 // Get the maximum call stack size.
393 unsigned maxCallFrameSize = MFI->getMaxCallFrameSize();
394 // Get the total frame size.
395 unsigned FrameSize = MFI->getStackSize();
397 // Get stack alignments.
398 unsigned TargetAlign = MF.getTarget().getFrameLowering()->getStackAlignment();
399 unsigned MaxAlign = MFI->getMaxAlignment();
400 if (MaxAlign > TargetAlign)
401 report_fatal_error("Dynamic alloca with large aligns not supported");
403 // Determine the previous frame's address. If FrameSize can't be
404 // represented as 16 bits or we need special alignment, then we load the
405 // previous frame's address from 0(SP). Why not do an addis of the hi?
406 // Because R0 is our only safe tmp register and addi/addis treat R0 as zero.
407 // Constructing the constant and adding would take 3 instructions.
408 // Fortunately, a frame greater than 32K is rare.
409 const TargetRegisterClass *G8RC = &PPC::G8RCRegClass;
410 const TargetRegisterClass *GPRC = &PPC::GPRCRegClass;
411 const TargetRegisterClass *RC = LP64 ? G8RC : GPRC;
413 // FIXME (64-bit): Use "findScratchRegister"
415 if (requiresRegisterScavenging(MF))
416 Reg = findScratchRegister(II, RS, RC, SPAdj);
420 if (MaxAlign < TargetAlign && isInt<16>(FrameSize)) {
421 BuildMI(MBB, II, dl, TII.get(PPC::ADDI), Reg)
425 if (requiresRegisterScavenging(MF)) // FIXME (64-bit): Use "true" part.
426 BuildMI(MBB, II, dl, TII.get(PPC::LD), Reg)
430 BuildMI(MBB, II, dl, TII.get(PPC::LD), PPC::X0)
434 BuildMI(MBB, II, dl, TII.get(PPC::LWZ), Reg)
439 // Grow the stack and update the stack pointer link, then determine the
440 // address of new allocated space.
442 if (requiresRegisterScavenging(MF)) // FIXME (64-bit): Use "true" part.
443 BuildMI(MBB, II, dl, TII.get(PPC::STDUX))
444 .addReg(Reg, RegState::Kill)
446 .addReg(MI.getOperand(1).getReg());
448 BuildMI(MBB, II, dl, TII.get(PPC::STDUX))
449 .addReg(PPC::X0, RegState::Kill)
451 .addReg(MI.getOperand(1).getReg());
453 if (!MI.getOperand(1).isKill())
454 BuildMI(MBB, II, dl, TII.get(PPC::ADDI8), MI.getOperand(0).getReg())
456 .addImm(maxCallFrameSize);
458 // Implicitly kill the register.
459 BuildMI(MBB, II, dl, TII.get(PPC::ADDI8), MI.getOperand(0).getReg())
461 .addImm(maxCallFrameSize)
462 .addReg(MI.getOperand(1).getReg(), RegState::ImplicitKill);
464 BuildMI(MBB, II, dl, TII.get(PPC::STWUX))
465 .addReg(Reg, RegState::Kill)
467 .addReg(MI.getOperand(1).getReg());
469 if (!MI.getOperand(1).isKill())
470 BuildMI(MBB, II, dl, TII.get(PPC::ADDI), MI.getOperand(0).getReg())
472 .addImm(maxCallFrameSize);
474 // Implicitly kill the register.
475 BuildMI(MBB, II, dl, TII.get(PPC::ADDI), MI.getOperand(0).getReg())
477 .addImm(maxCallFrameSize)
478 .addReg(MI.getOperand(1).getReg(), RegState::ImplicitKill);
481 // Discard the DYNALLOC instruction.
485 /// lowerCRSpilling - Generate the code for spilling a CR register. Instead of
486 /// reserving a whole register (R0), we scrounge for one here. This generates
489 /// mfcr rA ; Move the conditional register into GPR rA.
490 /// rlwinm rA, rA, SB, 0, 31 ; Shift the bits left so they are in CR0's slot.
491 /// stw rA, FI ; Store rA to the frame.
493 void PPCRegisterInfo::lowerCRSpilling(MachineBasicBlock::iterator II,
494 unsigned FrameIndex, int SPAdj,
495 RegScavenger *RS) const {
496 // Get the instruction.
497 MachineInstr &MI = *II; // ; SPILL_CR <SrcReg>, <offset>, <FI>
498 // Get the instruction's basic block.
499 MachineBasicBlock &MBB = *MI.getParent();
500 DebugLoc dl = MI.getDebugLoc();
502 const TargetRegisterClass *G8RC = &PPC::G8RCRegClass;
503 const TargetRegisterClass *GPRC = &PPC::GPRCRegClass;
504 const TargetRegisterClass *RC = Subtarget.isPPC64() ? G8RC : GPRC;
505 unsigned Reg = findScratchRegister(II, RS, RC, SPAdj);
506 unsigned SrcReg = MI.getOperand(0).getReg();
508 // We need to store the CR in the low 4-bits of the saved value. First, issue
509 // an MFCRpsued to save all of the CRBits and, if needed, kill the SrcReg.
510 BuildMI(MBB, II, dl, TII.get(PPC::MFCRpseud), Reg)
511 .addReg(SrcReg, getKillRegState(MI.getOperand(0).isKill()));
513 // If the saved register wasn't CR0, shift the bits left so that they are in
515 if (SrcReg != PPC::CR0)
516 // rlwinm rA, rA, ShiftBits, 0, 31.
517 BuildMI(MBB, II, dl, TII.get(PPC::RLWINM), Reg)
518 .addReg(Reg, RegState::Kill)
519 .addImm(PPCRegisterInfo::getRegisterNumbering(SrcReg) * 4)
523 addFrameReference(BuildMI(MBB, II, dl, TII.get(PPC::STW))
524 .addReg(Reg, getKillRegState(MI.getOperand(1).getImm())),
527 // Discard the pseudo instruction.
532 PPCRegisterInfo::eliminateFrameIndex(MachineBasicBlock::iterator II,
533 int SPAdj, RegScavenger *RS) const {
534 assert(SPAdj == 0 && "Unexpected");
536 // Get the instruction.
537 MachineInstr &MI = *II;
538 // Get the instruction's basic block.
539 MachineBasicBlock &MBB = *MI.getParent();
540 // Get the basic block's function.
541 MachineFunction &MF = *MBB.getParent();
542 // Get the frame info.
543 MachineFrameInfo *MFI = MF.getFrameInfo();
544 const TargetFrameLowering *TFI = MF.getTarget().getFrameLowering();
545 DebugLoc dl = MI.getDebugLoc();
547 // Find out which operand is the frame index.
548 unsigned FIOperandNo = 0;
549 while (!MI.getOperand(FIOperandNo).isFI()) {
551 assert(FIOperandNo != MI.getNumOperands() &&
552 "Instr doesn't have FrameIndex operand!");
554 // Take into account whether it's an add or mem instruction
555 unsigned OffsetOperandNo = (FIOperandNo == 2) ? 1 : 2;
556 if (MI.isInlineAsm())
557 OffsetOperandNo = FIOperandNo-1;
559 // Get the frame index.
560 int FrameIndex = MI.getOperand(FIOperandNo).getIndex();
562 // Get the frame pointer save index. Users of this index are primarily
563 // DYNALLOC instructions.
564 PPCFunctionInfo *FI = MF.getInfo<PPCFunctionInfo>();
565 int FPSI = FI->getFramePointerSaveIndex();
566 // Get the instruction opcode.
567 unsigned OpC = MI.getOpcode();
569 // Special case for dynamic alloca.
570 if (FPSI && FrameIndex == FPSI &&
571 (OpC == PPC::DYNALLOC || OpC == PPC::DYNALLOC8)) {
572 lowerDynamicAlloc(II, SPAdj, RS);
576 // Special case for pseudo-op SPILL_CR.
577 if (requiresRegisterScavenging(MF)) // FIXME (64-bit): Enable by default.
578 if (OpC == PPC::SPILL_CR) {
579 lowerCRSpilling(II, FrameIndex, SPAdj, RS);
583 // Replace the FrameIndex with base register with GPR1 (SP) or GPR31 (FP).
584 MI.getOperand(FIOperandNo).ChangeToRegister(TFI->hasFP(MF) ?
588 // Figure out if the offset in the instruction is shifted right two bits. This
589 // is true for instructions like "STD", which the machine implicitly adds two
591 bool isIXAddr = false;
601 // Now add the frame object offset to the offset from r1.
602 int Offset = MFI->getObjectOffset(FrameIndex);
604 Offset += MI.getOperand(OffsetOperandNo).getImm();
606 Offset += MI.getOperand(OffsetOperandNo).getImm() << 2;
608 // If we're not using a Frame Pointer that has been set to the value of the
609 // SP before having the stack size subtracted from it, then add the stack size
610 // to Offset to get the correct offset.
611 // Naked functions have stack size 0, although getStackSize may not reflect that
612 // because we didn't call all the pieces that compute it for naked functions.
613 if (!MF.getFunction()->hasFnAttr(Attribute::Naked))
614 Offset += MFI->getStackSize();
616 // If we can, encode the offset directly into the instruction. If this is a
617 // normal PPC "ri" instruction, any 16-bit value can be safely encoded. If
618 // this is a PPC64 "ix" instruction, only a 16-bit value with the low two bits
619 // clear can be encoded. This is extremely uncommon, because normally you
620 // only "std" to a stack slot that is at least 4-byte aligned, but it can
621 // happen in invalid code.
622 if (isInt<16>(Offset) && (!isIXAddr || (Offset & 3) == 0)) {
624 Offset >>= 2; // The actual encoded value has the low two bits zero.
625 MI.getOperand(OffsetOperandNo).ChangeToImmediate(Offset);
629 // The offset doesn't fit into a single register, scavenge one to build the
631 // FIXME: figure out what SPAdj is doing here.
633 // FIXME (64-bit): Use "findScratchRegister".
635 if (requiresRegisterScavenging(MF))
636 SReg = findScratchRegister(II, RS, &PPC::GPRCRegClass, SPAdj);
640 // Insert a set of rA with the full offset value before the ld, st, or add
641 BuildMI(MBB, II, dl, TII.get(PPC::LIS), SReg)
642 .addImm(Offset >> 16);
643 BuildMI(MBB, II, dl, TII.get(PPC::ORI), SReg)
644 .addReg(SReg, RegState::Kill)
647 // Convert into indexed form of the instruction:
649 // sth 0:rA, 1:imm 2:(rB) ==> sthx 0:rA, 2:rB, 1:r0
650 // addi 0:rA 1:rB, 2, imm ==> add 0:rA, 1:rB, 2:r0
651 unsigned OperandBase;
653 if (OpC != TargetOpcode::INLINEASM) {
654 assert(ImmToIdxMap.count(OpC) &&
655 "No indexed form of load or store available!");
656 unsigned NewOpcode = ImmToIdxMap.find(OpC)->second;
657 MI.setDesc(TII.get(NewOpcode));
660 OperandBase = OffsetOperandNo;
663 unsigned StackReg = MI.getOperand(FIOperandNo).getReg();
664 MI.getOperand(OperandBase).ChangeToRegister(StackReg, false);
665 MI.getOperand(OperandBase + 1).ChangeToRegister(SReg, false);
668 unsigned PPCRegisterInfo::getRARegister() const {
669 return !Subtarget.isPPC64() ? PPC::LR : PPC::LR8;
672 unsigned PPCRegisterInfo::getFrameRegister(const MachineFunction &MF) const {
673 const TargetFrameLowering *TFI = MF.getTarget().getFrameLowering();
675 if (!Subtarget.isPPC64())
676 return TFI->hasFP(MF) ? PPC::R31 : PPC::R1;
678 return TFI->hasFP(MF) ? PPC::X31 : PPC::X1;
681 unsigned PPCRegisterInfo::getEHExceptionRegister() const {
682 return !Subtarget.isPPC64() ? PPC::R3 : PPC::X3;
685 unsigned PPCRegisterInfo::getEHHandlerRegister() const {
686 return !Subtarget.isPPC64() ? PPC::R4 : PPC::X4;
689 /// DWARFFlavour - Flavour of dwarf regnumbers
691 namespace DWARFFlavour {
697 int PPCRegisterInfo::getDwarfRegNum(unsigned RegNum, bool isEH) const {
698 // FIXME: Most probably dwarf numbers differs for Linux and Darwin
699 unsigned Flavour = Subtarget.isPPC64() ?
700 DWARFFlavour::PPC64 : DWARFFlavour::PPC32;
702 return PPCGenRegisterInfo::getDwarfRegNumFull(RegNum, Flavour);
705 #include "PPCGenRegisterInfo.inc"