1 //===-- AMDGPUAsmPrinter.cpp - AMDGPU Assebly printer --------------------===//
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 //===----------------------------------------------------------------------===//
12 /// The AMDGPUAsmPrinter is used to print both assembly string and also binary
13 /// code. When passed an MCAsmStreamer it prints assembly and when passed
14 /// an MCObjectStreamer it outputs binary code.
16 //===----------------------------------------------------------------------===//
19 #include "AMDGPUAsmPrinter.h"
21 #include "AMDGPUSubtarget.h"
22 #include "R600Defines.h"
23 #include "R600MachineFunctionInfo.h"
24 #include "R600RegisterInfo.h"
25 #include "SIDefines.h"
26 #include "SIMachineFunctionInfo.h"
27 #include "SIRegisterInfo.h"
28 #include "llvm/CodeGen/MachineFrameInfo.h"
29 #include "llvm/MC/MCContext.h"
30 #include "llvm/MC/MCSectionELF.h"
31 #include "llvm/MC/MCStreamer.h"
32 #include "llvm/Support/ELF.h"
33 #include "llvm/Support/MathExtras.h"
34 #include "llvm/Support/TargetRegistry.h"
35 #include "llvm/Target/TargetLoweringObjectFile.h"
39 // TODO: This should get the default rounding mode from the kernel. We just set
40 // the default here, but this could change if the OpenCL rounding mode pragmas
43 // The denormal mode here should match what is reported by the OpenCL runtime
44 // for the CL_FP_DENORM bit from CL_DEVICE_{HALF|SINGLE|DOUBLE}_FP_CONFIG, but
45 // can also be override to flush with the -cl-denorms-are-zero compiler flag.
47 // AMD OpenCL only sets flush none and reports CL_FP_DENORM for double
48 // precision, and leaves single precision to flush all and does not report
49 // CL_FP_DENORM for CL_DEVICE_SINGLE_FP_CONFIG. Mesa's OpenCL currently reports
50 // CL_FP_DENORM for both.
52 // FIXME: It seems some instructions do not support single precision denormals
53 // regardless of the mode (exp_*_f32, rcp_*_f32, rsq_*_f32, rsq_*f32, sqrt_f32,
54 // and sin_f32, cos_f32 on most parts).
56 // We want to use these instructions, and using fp32 denormals also causes
57 // instructions to run at the double precision rate for the device so it's
58 // probably best to just report no single precision denormals.
59 static uint32_t getFPMode(const MachineFunction &F) {
60 const AMDGPUSubtarget& ST = F.getTarget().getSubtarget<AMDGPUSubtarget>();
61 // TODO: Is there any real use for the flush in only / flush out only modes?
63 uint32_t FP32Denormals =
64 ST.hasFP32Denormals() ? FP_DENORM_FLUSH_NONE : FP_DENORM_FLUSH_IN_FLUSH_OUT;
66 uint32_t FP64Denormals =
67 ST.hasFP64Denormals() ? FP_DENORM_FLUSH_NONE : FP_DENORM_FLUSH_IN_FLUSH_OUT;
69 return FP_ROUND_MODE_SP(FP_ROUND_ROUND_TO_NEAREST) |
70 FP_ROUND_MODE_DP(FP_ROUND_ROUND_TO_NEAREST) |
71 FP_DENORM_MODE_SP(FP32Denormals) |
72 FP_DENORM_MODE_DP(FP64Denormals);
75 static AsmPrinter *createAMDGPUAsmPrinterPass(TargetMachine &tm,
76 MCStreamer &Streamer) {
77 return new AMDGPUAsmPrinter(tm, Streamer);
80 extern "C" void LLVMInitializeR600AsmPrinter() {
81 TargetRegistry::RegisterAsmPrinter(TheAMDGPUTarget, createAMDGPUAsmPrinterPass);
84 AMDGPUAsmPrinter::AMDGPUAsmPrinter(TargetMachine &TM, MCStreamer &Streamer)
85 : AsmPrinter(TM, Streamer) {
86 DisasmEnabled = TM.getSubtarget<AMDGPUSubtarget>().dumpCode();
89 void AMDGPUAsmPrinter::EmitEndOfAsmFile(Module &M) {
91 // This label is used to mark the end of the .text section.
92 const TargetLoweringObjectFile &TLOF = getObjFileLowering();
93 OutStreamer.SwitchSection(TLOF.getTextSection());
94 MCSymbol *EndOfTextLabel =
95 OutContext.GetOrCreateSymbol(StringRef(END_OF_TEXT_LABEL_NAME));
96 OutStreamer.EmitLabel(EndOfTextLabel);
99 bool AMDGPUAsmPrinter::runOnMachineFunction(MachineFunction &MF) {
101 // The starting address of all shader programs must be 256 bytes aligned.
104 SetupMachineFunction(MF);
106 EmitFunctionHeader();
108 MCContext &Context = getObjFileLowering().getContext();
109 const MCSectionELF *ConfigSection = Context.getELFSection(".AMDGPU.config",
110 ELF::SHT_PROGBITS, 0,
111 SectionKind::getReadOnly());
112 OutStreamer.SwitchSection(ConfigSection);
114 const AMDGPUSubtarget &STM = TM.getSubtarget<AMDGPUSubtarget>();
115 SIProgramInfo KernelInfo;
116 if (STM.getGeneration() > AMDGPUSubtarget::NORTHERN_ISLANDS) {
117 getSIProgramInfo(KernelInfo, MF);
118 EmitProgramInfoSI(MF, KernelInfo);
120 EmitProgramInfoR600(MF);
125 DisasmLineMaxLen = 0;
127 OutStreamer.SwitchSection(getObjFileLowering().getTextSection());
131 const MCSectionELF *CommentSection
132 = Context.getELFSection(".AMDGPU.csdata",
133 ELF::SHT_PROGBITS, 0,
134 SectionKind::getReadOnly());
135 OutStreamer.SwitchSection(CommentSection);
137 if (STM.getGeneration() >= AMDGPUSubtarget::SOUTHERN_ISLANDS) {
138 OutStreamer.emitRawComment(" Kernel info:", false);
139 OutStreamer.emitRawComment(" codeLenInByte = " + Twine(KernelInfo.CodeLen),
141 OutStreamer.emitRawComment(" NumSgprs: " + Twine(KernelInfo.NumSGPR),
143 OutStreamer.emitRawComment(" NumVgprs: " + Twine(KernelInfo.NumVGPR),
145 OutStreamer.emitRawComment(" FloatMode: " + Twine(KernelInfo.FloatMode),
147 OutStreamer.emitRawComment(" IeeeMode: " + Twine(KernelInfo.IEEEMode),
149 OutStreamer.emitRawComment(" ScratchSize: " + Twine(KernelInfo.ScratchSize),
152 R600MachineFunctionInfo *MFI = MF.getInfo<R600MachineFunctionInfo>();
153 OutStreamer.emitRawComment(
154 Twine("SQ_PGM_RESOURCES:STACK_SIZE = " + Twine(MFI->StackSize)));
158 if (STM.dumpCode()) {
159 #if !defined(NDEBUG) || defined(LLVM_ENABLE_DUMP)
164 OutStreamer.SwitchSection(Context.getELFSection(".AMDGPU.disasm",
166 SectionKind::getReadOnly()));
168 for (size_t i = 0; i < DisasmLines.size(); ++i) {
169 std::string Comment(DisasmLineMaxLen - DisasmLines[i].size(), ' ');
170 Comment += " ; " + HexLines[i] + "\n";
172 OutStreamer.EmitBytes(StringRef(DisasmLines[i]));
173 OutStreamer.EmitBytes(StringRef(Comment));
181 void AMDGPUAsmPrinter::EmitProgramInfoR600(const MachineFunction &MF) {
183 bool killPixel = false;
184 const R600RegisterInfo *RI = static_cast<const R600RegisterInfo *>(
185 TM.getSubtargetImpl()->getRegisterInfo());
186 const R600MachineFunctionInfo *MFI = MF.getInfo<R600MachineFunctionInfo>();
187 const AMDGPUSubtarget &STM = TM.getSubtarget<AMDGPUSubtarget>();
189 for (const MachineBasicBlock &MBB : MF) {
190 for (const MachineInstr &MI : MBB) {
191 if (MI.getOpcode() == AMDGPU::KILLGT)
193 unsigned numOperands = MI.getNumOperands();
194 for (unsigned op_idx = 0; op_idx < numOperands; op_idx++) {
195 const MachineOperand &MO = MI.getOperand(op_idx);
198 unsigned HWReg = RI->getEncodingValue(MO.getReg()) & 0xff;
200 // Register with value > 127 aren't GPR
203 MaxGPR = std::max(MaxGPR, HWReg);
209 if (STM.getGeneration() >= AMDGPUSubtarget::EVERGREEN) {
210 // Evergreen / Northern Islands
211 switch (MFI->getShaderType()) {
212 default: // Fall through
213 case ShaderType::COMPUTE: RsrcReg = R_0288D4_SQ_PGM_RESOURCES_LS; break;
214 case ShaderType::GEOMETRY: RsrcReg = R_028878_SQ_PGM_RESOURCES_GS; break;
215 case ShaderType::PIXEL: RsrcReg = R_028844_SQ_PGM_RESOURCES_PS; break;
216 case ShaderType::VERTEX: RsrcReg = R_028860_SQ_PGM_RESOURCES_VS; break;
220 switch (MFI->getShaderType()) {
221 default: // Fall through
222 case ShaderType::GEOMETRY: // Fall through
223 case ShaderType::COMPUTE: // Fall through
224 case ShaderType::VERTEX: RsrcReg = R_028868_SQ_PGM_RESOURCES_VS; break;
225 case ShaderType::PIXEL: RsrcReg = R_028850_SQ_PGM_RESOURCES_PS; break;
229 OutStreamer.EmitIntValue(RsrcReg, 4);
230 OutStreamer.EmitIntValue(S_NUM_GPRS(MaxGPR + 1) |
231 S_STACK_SIZE(MFI->StackSize), 4);
232 OutStreamer.EmitIntValue(R_02880C_DB_SHADER_CONTROL, 4);
233 OutStreamer.EmitIntValue(S_02880C_KILL_ENABLE(killPixel), 4);
235 if (MFI->getShaderType() == ShaderType::COMPUTE) {
236 OutStreamer.EmitIntValue(R_0288E8_SQ_LDS_ALLOC, 4);
237 OutStreamer.EmitIntValue(RoundUpToAlignment(MFI->LDSSize, 4) >> 2, 4);
241 void AMDGPUAsmPrinter::getSIProgramInfo(SIProgramInfo &ProgInfo,
242 const MachineFunction &MF) const {
243 uint64_t CodeSize = 0;
244 unsigned MaxSGPR = 0;
245 unsigned MaxVGPR = 0;
246 bool VCCUsed = false;
247 bool FlatUsed = false;
248 const SIRegisterInfo *RI = static_cast<const SIRegisterInfo *>(
249 TM.getSubtargetImpl()->getRegisterInfo());
251 for (const MachineBasicBlock &MBB : MF) {
252 for (const MachineInstr &MI : MBB) {
253 // TODO: CodeSize should account for multiple functions.
254 CodeSize += MI.getDesc().Size;
256 unsigned numOperands = MI.getNumOperands();
257 for (unsigned op_idx = 0; op_idx < numOperands; op_idx++) {
258 const MachineOperand &MO = MI.getOperand(op_idx);
265 unsigned reg = MO.getReg();
266 if (reg == AMDGPU::VCC || reg == AMDGPU::VCC_LO ||
267 reg == AMDGPU::VCC_HI) {
270 } else if (reg == AMDGPU::FLAT_SCR ||
271 reg == AMDGPU::FLAT_SCR_LO ||
272 reg == AMDGPU::FLAT_SCR_HI) {
285 if (AMDGPU::SReg_32RegClass.contains(reg)) {
288 } else if (AMDGPU::VReg_32RegClass.contains(reg)) {
291 } else if (AMDGPU::SReg_64RegClass.contains(reg)) {
294 } else if (AMDGPU::VReg_64RegClass.contains(reg)) {
297 } else if (AMDGPU::VReg_96RegClass.contains(reg)) {
300 } else if (AMDGPU::SReg_128RegClass.contains(reg)) {
303 } else if (AMDGPU::VReg_128RegClass.contains(reg)) {
306 } else if (AMDGPU::SReg_256RegClass.contains(reg)) {
309 } else if (AMDGPU::VReg_256RegClass.contains(reg)) {
312 } else if (AMDGPU::SReg_512RegClass.contains(reg)) {
315 } else if (AMDGPU::VReg_512RegClass.contains(reg)) {
319 llvm_unreachable("Unknown register class");
321 unsigned hwReg = RI->getEncodingValue(reg) & 0xff;
322 unsigned maxUsed = hwReg + width - 1;
324 MaxSGPR = maxUsed > MaxSGPR ? maxUsed : MaxSGPR;
326 MaxVGPR = maxUsed > MaxVGPR ? maxUsed : MaxVGPR;
338 // We found the maximum register index. They start at 0, so add one to get the
339 // number of registers.
340 ProgInfo.NumVGPR = MaxVGPR + 1;
341 ProgInfo.NumSGPR = MaxSGPR + 1;
343 // Set the value to initialize FP_ROUND and FP_DENORM parts of the mode
345 ProgInfo.FloatMode = getFPMode(MF);
347 // XXX: Not quite sure what this does, but sc seems to unset this.
348 ProgInfo.IEEEMode = 0;
350 // Do not clamp NAN to 0.
351 ProgInfo.DX10Clamp = 0;
353 const MachineFrameInfo *FrameInfo = MF.getFrameInfo();
354 ProgInfo.ScratchSize = FrameInfo->estimateStackSize(MF);
356 ProgInfo.FlatUsed = FlatUsed;
357 ProgInfo.VCCUsed = VCCUsed;
358 ProgInfo.CodeLen = CodeSize;
361 void AMDGPUAsmPrinter::EmitProgramInfoSI(const MachineFunction &MF,
362 const SIProgramInfo &KernelInfo) {
363 const AMDGPUSubtarget &STM = TM.getSubtarget<AMDGPUSubtarget>();
364 const SIMachineFunctionInfo *MFI = MF.getInfo<SIMachineFunctionInfo>();
367 switch (MFI->getShaderType()) {
368 default: // Fall through
369 case ShaderType::COMPUTE: RsrcReg = R_00B848_COMPUTE_PGM_RSRC1; break;
370 case ShaderType::GEOMETRY: RsrcReg = R_00B228_SPI_SHADER_PGM_RSRC1_GS; break;
371 case ShaderType::PIXEL: RsrcReg = R_00B028_SPI_SHADER_PGM_RSRC1_PS; break;
372 case ShaderType::VERTEX: RsrcReg = R_00B128_SPI_SHADER_PGM_RSRC1_VS; break;
375 unsigned LDSAlignShift;
376 if (STM.getGeneration() < AMDGPUSubtarget::SEA_ISLANDS) {
377 // LDS is allocated in 64 dword blocks.
380 // LDS is allocated in 128 dword blocks.
384 unsigned LDSSpillSize = MFI->LDSWaveSpillSize *
385 MFI->getMaximumWorkGroupSize(MF);
388 RoundUpToAlignment(MFI->LDSSize + LDSSpillSize,
389 1 << LDSAlignShift) >> LDSAlignShift;
391 // Scratch is allocated in 256 dword blocks.
392 unsigned ScratchAlignShift = 10;
393 // We need to program the hardware with the amount of scratch memory that
394 // is used by the entire wave. KernelInfo.ScratchSize is the amount of
395 // scratch memory used per thread.
396 unsigned ScratchBlocks =
397 RoundUpToAlignment(KernelInfo.ScratchSize * STM.getWavefrontSize(),
398 1 << ScratchAlignShift) >> ScratchAlignShift;
400 unsigned VGPRBlocks = (KernelInfo.NumVGPR - 1) / 4;
401 unsigned SGPRBlocks = (KernelInfo.NumSGPR - 1) / 8;
403 if (MFI->getShaderType() == ShaderType::COMPUTE) {
404 OutStreamer.EmitIntValue(R_00B848_COMPUTE_PGM_RSRC1, 4);
406 const uint32_t ComputePGMRSrc1 =
407 S_00B848_VGPRS(VGPRBlocks) |
408 S_00B848_SGPRS(SGPRBlocks) |
409 S_00B848_PRIORITY(KernelInfo.Priority) |
410 S_00B848_FLOAT_MODE(KernelInfo.FloatMode) |
411 S_00B848_PRIV(KernelInfo.Priv) |
412 S_00B848_DX10_CLAMP(KernelInfo.DX10Clamp) |
413 S_00B848_IEEE_MODE(KernelInfo.DebugMode) |
414 S_00B848_IEEE_MODE(KernelInfo.IEEEMode);
416 OutStreamer.EmitIntValue(ComputePGMRSrc1, 4);
418 OutStreamer.EmitIntValue(R_00B84C_COMPUTE_PGM_RSRC2, 4);
419 const uint32_t ComputePGMRSrc2 =
420 S_00B84C_LDS_SIZE(LDSBlocks) |
421 S_00B02C_SCRATCH_EN(ScratchBlocks > 0);
423 OutStreamer.EmitIntValue(ComputePGMRSrc2, 4);
425 OutStreamer.EmitIntValue(R_00B860_COMPUTE_TMPRING_SIZE, 4);
426 OutStreamer.EmitIntValue(S_00B860_WAVESIZE(ScratchBlocks), 4);
428 // TODO: Should probably note flat usage somewhere. SC emits a "FlatPtr32 =
429 // 0" comment but I don't see a corresponding field in the register spec.
431 OutStreamer.EmitIntValue(RsrcReg, 4);
432 OutStreamer.EmitIntValue(S_00B028_VGPRS(VGPRBlocks) |
433 S_00B028_SGPRS(SGPRBlocks), 4);
436 if (MFI->getShaderType() == ShaderType::PIXEL) {
437 OutStreamer.EmitIntValue(R_00B02C_SPI_SHADER_PGM_RSRC2_PS, 4);
438 OutStreamer.EmitIntValue(S_00B02C_EXTRA_LDS_SIZE(LDSBlocks), 4);
439 OutStreamer.EmitIntValue(R_0286CC_SPI_PS_INPUT_ENA, 4);
440 OutStreamer.EmitIntValue(MFI->PSInputAddr, 4);