Fixed masking/casting logic in commit log printf.
[riscv-isa-sim.git] / riscv / processor.cc
index e04f4985d74ceea9633b9f0f29335ecad78e70f6..0a344465df6b39ddf981e22b8c28f3ea4f67eeb2 100644 (file)
+// See LICENSE for license details.
+
 #include "processor.h"
-#include <bfd.h>
-#include <dis-asm.h>
-#include <cmath>
-#include <cstdlib>
-#include <iostream>
+#include "extension.h"
 #include "common.h"
 #include "config.h"
 #include "sim.h"
-#include "softfloat.h"
+#include "htif.h"
+#include "disasm.h"
+#include <cinttypes>
+#include <cmath>
+#include <cstdlib>
+#include <iostream>
+#include <assert.h>
+#include <limits.h>
+#include <stdexcept>
+#include <algorithm>
 
-processor_t::processor_t(sim_t* _sim, char* _mem, size_t _memsz)
-  : sim(_sim), mmu(_mem,_memsz)
+#undef STATE
+#define STATE state
+
+processor_t::processor_t(sim_t* _sim, mmu_t* _mmu, uint32_t _id)
+  : sim(_sim), mmu(_mmu), ext(NULL), disassembler(new disassembler_t),
+    id(_id), run(false), debug(false), serialized(false)
+{
+  reset(true);
+  mmu->set_processor(this);
+
+  #define DECLARE_INSN(name, match, mask) REGISTER_INSN(this, name, match, mask)
+  #include "encoding.h"
+  #undef DECLARE_INSN
+  build_opcode_map();
+}
+
+processor_t::~processor_t()
 {
-  memset(R,0,sizeof(R));
-  memset(FR,0,sizeof(FR));
-  pc = 0;
-  ebase = 0;
+#ifdef RISCV_ENABLE_HISTOGRAM
+  if (histogram_enabled)
+  {
+    fprintf(stderr, "PC Histogram size:%lu\n", pc_histogram.size());
+    for(auto iterator = pc_histogram.begin(); iterator != pc_histogram.end(); ++iterator) {
+      fprintf(stderr, "%0lx %lu\n", (iterator->first << 2), iterator->second);
+    }
+  }
+#endif
+
+  delete disassembler;
+}
+
+void state_t::reset()
+{
+  // the ISA guarantees on boot that the PC is 0x2000 and the the processor
+  // is in supervisor mode, and in 64-bit mode, if supported, with traps
+  // and virtual memory disabled.
+  sr = SR_S | SR_S64 | SR_U64;
+  pc = 0x2000;
+
+  // the following state is undefined upon boot-up,
+  // but we zero it for determinism
+  XPR.reset();
+  FPR.reset();
+
   epc = 0;
   badvaddr = 0;
-  tid = 0;
+  evec = 0;
+  ptbr = 0;
   pcr_k0 = 0;
   pcr_k1 = 0;
+  cause = 0;
+  tohost = 0;
+  fromhost = 0;
   count = 0;
   compare = 0;
-  interrupts_pending = 0;
-  set_sr(SR_S | (support_64bit ? SR_SX : 0));
-  set_fsr(0);
+  fflags = 0;
+  frm = 0;
+
+  load_reservation = -1;
+}
+
+void processor_t::set_debug(bool value)
+{
+  debug = value;
+  if (ext)
+    ext->set_debug(value);
+}
 
-  memset(counters,0,sizeof(counters));
+void processor_t::set_histogram(bool value)
+{
+  histogram_enabled = value;
+}
 
-  // a few assumptions about endianness, including freg_t union
-  static_assert(BYTE_ORDER == LITTLE_ENDIAN);
-  static_assert(sizeof(freg_t) == 8);
-  static_assert(sizeof(reg_t) == 8);
+void processor_t::reset(bool value)
+{
+  if (run == !value)
+    return;
+  run = !value;
+
+  state.reset(); // reset the core
+  set_pcr(CSR_STATUS, state.sr);
 
-  static_assert(sizeof(insn_t) == 4);
-  static_assert(sizeof(uint128_t) == 16 && sizeof(int128_t) == 16);
+  if (ext)
+    ext->reset(); // reset the extension
 }
 
-void processor_t::init(uint32_t _id)
+struct serialize_t {};
+
+void processor_t::serialize()
 {
-  id = _id;
+  if (serialized)
+    serialized = false;
+  else
+    serialized = true, throw serialize_t();
 }
 
-void processor_t::set_sr(uint32_t val)
+void processor_t::take_interrupt()
 {
-  sr = val & ~SR_ZERO;
-  if(!support_64bit)
-    sr &= ~(SR_SX | SR_UX);
+  int irqs = ((state.sr & SR_IP) >> SR_IP_SHIFT) & (state.sr >> SR_IM_SHIFT);
+  if (likely(!irqs) || likely(!(state.sr & SR_EI)))
+    return;
+
+  for (int i = 0; ; i++)
+    if ((irqs >> i) & 1)
+      throw trap_t((1ULL << ((state.sr & SR_S64) ? 63 : 31)) + i);
+}
 
-  gprlen = ((sr & SR_S) ? (sr & SR_SX) : (sr & SR_UX)) ? 64 : 32;
+static void commit_log(state_t* state, reg_t pc, insn_t insn)
+{
+#ifdef RISCV_ENABLE_COMMITLOG
+  if (state->sr & SR_EI) {
+    uint64_t mask = (insn.length() == 8 ? uint64_t(0) : (uint64_t(1) << (insn.length() * 8))) - 1;
+    if (state->log_reg_write.addr) {
+      fprintf(stderr, "0x%016" PRIx64 " (0x%08" PRIx64 ") %c%2" PRIu64 " 0x%016" PRIx64 "\n",
+              pc,
+              insn.bits() & mask,
+              state->log_reg_write.addr & 1 ? 'f' : 'x',
+              state->log_reg_write.addr >> 1,
+              state->log_reg_write.data);
+    } else {
+      fprintf(stderr, "0x%016" PRIx64 " (0x%08" PRIx64 ")\n", pc, insn.bits() & mask);
+    }
+  }
+  state->log_reg_write.addr = 0;
+#endif
 }
 
-void processor_t::set_fsr(uint32_t val)
+inline void processor_t::update_histogram(size_t pc)
 {
-  fsr = val & ~FSR_ZERO;
-  softfloat_roundingMode = (fsr & FSR_RD) >> FSR_RD_SHIFT;
+#ifdef RISCV_ENABLE_HISTOGRAM
+  size_t idx = pc >> 2;
+  pc_histogram[idx]++;
+#endif
 }
 
-void processor_t::step(size_t n, bool noisy)
+static reg_t execute_insn(processor_t* p, reg_t pc, insn_fetch_t fetch)
 {
-  size_t i = 0;
-  while(1) try
+  reg_t npc = fetch.func(p, fetch.insn, pc);
+  commit_log(p->get_state(), pc, fetch.insn);
+  p->update_histogram(pc);
+  return npc;
+}
+
+static void update_timer(state_t* state, size_t instret)
+{
+  uint64_t count0 = (uint64_t)(uint32_t)state->count;
+  state->count += instret;
+  uint64_t before = count0 - state->compare;
+  if (int64_t(before ^ (before + instret)) < 0)
+    state->sr |= (1 << (IRQ_TIMER + SR_IP_SHIFT));
+}
+
+static size_t next_timer(state_t* state)
+{
+  return state->compare - (uint32_t)state->count;
+}
+
+void processor_t::step(size_t n)
+{
+  size_t instret = 0;
+  reg_t pc = state.pc;
+  mmu_t* _mmu = mmu;
+
+  if (unlikely(!run || !n))
+    return;
+  n = std::min(n, next_timer(&state) | 1U);
+
+  try
   {
-    for( ; i < n; i++)
+    take_interrupt();
+
+    if (unlikely(debug))
     {
-      uint32_t interrupts = interrupts_pending & ((sr & SR_IM) >> SR_IM_SHIFT);
-      if((sr & SR_ET) && interrupts)
+      while (instret++ < n)
       {
-        for(int i = 0; interrupts; i++, interrupts >>= 1)
-          if(interrupts & 1)
-            throw trap_t(16+i);
+        insn_fetch_t fetch = mmu->load_insn(pc);
+        disasm(fetch.insn);
+        pc = execute_insn(this, pc, fetch);
       }
+    }
+    else while (instret < n)
+    {
+      size_t idx = _mmu->icache_index(pc);
+      auto ic_entry = _mmu->access_icache(pc);
 
-      insn_t insn = mmu.load_insn(pc);
-  
-      reg_t npc = pc+sizeof(insn);
+      #define ICACHE_ACCESS(idx) { \
+        insn_fetch_t fetch = ic_entry->data; \
+        ic_entry++; \
+        pc = execute_insn(this, pc, fetch); \
+        instret++; \
+        if (idx == mmu_t::ICACHE_ENTRIES-1) break; \
+        if (unlikely(ic_entry->tag != pc)) break; \
+      }
 
-      if(noisy)
-        disasm(insn,pc);
+      switch (idx) {
+        #include "icache.h"
+      }
+    }
+  }
+  catch(trap_t& t)
+  {
+    pc = take_trap(t, pc);
+  }
+  catch(serialize_t& s) {}
 
-      #include "execute.h"
-  
-      pc = npc;
-      R[0] = 0;
+  state.pc = pc;
+  update_timer(&state, instret);
+}
 
-      if(count++ == compare)
-        interrupts_pending |= 1 << TIMER_IRQ;
-    }
-    return;
+reg_t processor_t::take_trap(trap_t& t, reg_t epc)
+{
+  if (debug)
+    fprintf(stderr, "core %3d: exception %s, epc 0x%016" PRIx64 "\n",
+            id, t.name(), epc);
+
+  // switch to supervisor, set previous supervisor bit, disable interrupts
+  set_pcr(CSR_STATUS, (((state.sr & ~SR_EI) | SR_S) & ~SR_PS & ~SR_PEI) |
+                      ((state.sr & SR_S) ? SR_PS : 0) |
+                      ((state.sr & SR_EI) ? SR_PEI : 0));
+
+  yield_load_reservation();
+  state.cause = t.cause();
+  state.epc = epc;
+  t.side_effects(&state); // might set badvaddr etc.
+  return state.evec;
+}
+
+void processor_t::deliver_ipi()
+{
+  if (run)
+    set_pcr(CSR_CLEAR_IPI, 1);
+}
+
+void processor_t::disasm(insn_t insn)
+{
+  uint64_t bits = insn.bits() & ((1ULL << (8 * insn_length(insn.bits()))) - 1);
+  fprintf(stderr, "core %3d: 0x%016" PRIx64 " (0x%08" PRIx64 ") %s\n",
+          id, state.pc, bits, disassembler->disassemble(insn).c_str());
+}
+
+void processor_t::set_pcr(int which, reg_t val)
+{
+  switch (which)
+  {
+    case CSR_FFLAGS:
+      state.fflags = val & (FSR_AEXC >> FSR_AEXC_SHIFT);
+      break;
+    case CSR_FRM:
+      state.frm = val & (FSR_RD >> FSR_RD_SHIFT);
+      break;
+    case CSR_FCSR:
+      state.fflags = (val & FSR_AEXC) >> FSR_AEXC_SHIFT;
+      state.frm = (val & FSR_RD) >> FSR_RD_SHIFT;
+      break;
+    case CSR_STATUS:
+      state.sr = (val & ~SR_IP) | (state.sr & SR_IP);
+#ifndef RISCV_ENABLE_64BIT
+      state.sr &= ~(SR_S64 | SR_U64);
+#endif
+#ifndef RISCV_ENABLE_FPU
+      state.sr &= ~SR_EF;
+#endif
+      if (!ext)
+        state.sr &= ~SR_EA;
+      state.sr &= ~SR_ZERO;
+      rv64 = (state.sr & SR_S) ? (state.sr & SR_S64) : (state.sr & SR_U64);
+      mmu->flush_tlb();
+      break;
+    case CSR_EPC:
+      state.epc = val;
+      break;
+    case CSR_EVEC:
+      state.evec = val & ~3;
+      break;
+    case CSR_COUNT:
+      state.count = val;
+      break;
+    case CSR_COUNTH:
+      state.count = (val << 32) | (uint32_t)state.count;
+      break;
+    case CSR_COMPARE:
+      serialize();
+      set_interrupt(IRQ_TIMER, false);
+      state.compare = val;
+      break;
+    case CSR_PTBR:
+      state.ptbr = val & ~(PGSIZE-1);
+      break;
+    case CSR_SEND_IPI:
+      sim->send_ipi(val);
+      break;
+    case CSR_CLEAR_IPI:
+      set_interrupt(IRQ_IPI, val & 1);
+      break;
+    case CSR_SUP0:
+      state.pcr_k0 = val;
+      break;
+    case CSR_SUP1:
+      state.pcr_k1 = val;
+      break;
+    case CSR_TOHOST:
+      if (state.tohost == 0)
+        state.tohost = val;
+      break;
+    case CSR_FROMHOST:
+      set_fromhost(val);
+      break;
   }
-  catch(trap_t t)
+}
+
+void processor_t::set_fromhost(reg_t val)
+{
+  set_interrupt(IRQ_HOST, val != 0);
+  state.fromhost = val;
+}
+
+reg_t processor_t::get_pcr(int which)
+{
+  switch (which)
   {
-    i++;
-    take_trap(t,noisy);
+    case CSR_FFLAGS:
+      require_fp;
+      return state.fflags;
+    case CSR_FRM:
+      require_fp;
+      return state.frm;
+    case CSR_FCSR:
+      require_fp;
+      return (state.fflags << FSR_AEXC_SHIFT) | (state.frm << FSR_RD_SHIFT);
+    case CSR_STATUS:
+      return state.sr;
+    case CSR_EPC:
+      return state.epc;
+    case CSR_BADVADDR:
+      return state.badvaddr;
+    case CSR_EVEC:
+      return state.evec;
+    case CSR_CYCLE:
+    case CSR_TIME:
+    case CSR_INSTRET:
+    case CSR_COUNT:
+      serialize();
+      return state.count;
+    case CSR_CYCLEH:
+    case CSR_TIMEH:
+    case CSR_INSTRETH:
+    case CSR_COUNTH:
+      if (rv64)
+        break;
+      serialize();
+      return state.count >> 32;
+    case CSR_COMPARE:
+      return state.compare;
+    case CSR_CAUSE:
+      return state.cause;
+    case CSR_PTBR:
+      return state.ptbr;
+    case CSR_SEND_IPI:
+    case CSR_CLEAR_IPI:
+      return 0;
+    case CSR_ASID:
+      return 0;
+    case CSR_FATC:
+      mmu->flush_tlb();
+      return 0;
+    case CSR_HARTID:
+      return id;
+    case CSR_IMPL:
+      return 1;
+    case CSR_SUP0:
+      return state.pcr_k0;
+    case CSR_SUP1:
+      return state.pcr_k1;
+    case CSR_TOHOST:
+      sim->get_htif()->tick(); // not necessary, but faster
+      return state.tohost;
+    case CSR_FROMHOST:
+      sim->get_htif()->tick(); // not necessary, but faster
+      return state.fromhost;
+    case CSR_UARCH0:
+    case CSR_UARCH1:
+    case CSR_UARCH2:
+    case CSR_UARCH3:
+    case CSR_UARCH4:
+    case CSR_UARCH5:
+    case CSR_UARCH6:
+    case CSR_UARCH7:
+    case CSR_UARCH8:
+    case CSR_UARCH9:
+    case CSR_UARCH10:
+    case CSR_UARCH11:
+    case CSR_UARCH12:
+    case CSR_UARCH13:
+    case CSR_UARCH14:
+    case CSR_UARCH15:
+      return 0;
   }
+  throw trap_illegal_instruction();
+}
+
+void processor_t::set_interrupt(int which, bool on)
+{
+  uint32_t mask = (1 << (which + SR_IP_SHIFT)) & SR_IP;
+  if (on)
+    state.sr |= mask;
+  else
+    state.sr &= ~mask;
+}
+
+reg_t illegal_instruction(processor_t* p, insn_t insn, reg_t pc)
+{
+  throw trap_illegal_instruction();
 }
 
-void processor_t::take_trap(trap_t t, bool noisy)
+insn_func_t processor_t::decode_insn(insn_t insn)
 {
-  demand(t < NUM_TRAPS, "internal error: bad trap number %d", int(t));
-  demand(sr & SR_ET, "error mode on core %d!\ntrap %s, pc 0x%016llx",
-         id, trap_name(t), (unsigned long long)pc);
-  if(noisy)
-    printf("core %3d: trap %s, pc 0x%016llx\n",
-           id, trap_name(t), (unsigned long long)pc);
+  size_t mask = opcode_map.size()-1;
+  insn_desc_t* desc = opcode_map[insn.bits() & mask]; 
 
-  set_sr((((sr & ~SR_ET) | SR_S) & ~SR_PS) | ((sr & SR_S) ? SR_PS : 0));
-  epc = pc;
-  pc = ebase + t*128;
-  badvaddr = mmu.get_badvaddr();
+  while ((insn.bits() & desc->mask) != desc->match)
+    desc++;
+
+  return rv64 ? desc->rv64 : desc->rv32;
+}
+
+void processor_t::register_insn(insn_desc_t desc)
+{
+  assert(desc.mask & 1);
+  instructions.push_back(desc);
 }
 
-void processor_t::disasm(insn_t insn, reg_t pc)
+void processor_t::build_opcode_map()
 {
-  printf("core %3d: 0x%016llx (0x%08x) ",id,(unsigned long long)pc,insn.bits);
+  size_t buckets = -1;
+  for (auto& inst : instructions)
+    while ((inst.mask & buckets) != buckets)
+      buckets /= 2;
+  buckets++;
+
+  struct cmp {
+    decltype(insn_desc_t::match) mask;
+    cmp(decltype(mask) mask) : mask(mask) {}
+    bool operator()(const insn_desc_t& lhs, const insn_desc_t& rhs) {
+      if ((lhs.match & mask) != (rhs.match & mask))
+        return (lhs.match & mask) < (rhs.match & mask);
+      return lhs.match < rhs.match;
+    }
+  };
+  std::sort(instructions.begin(), instructions.end(), cmp(buckets-1));
 
-  #ifdef RISCV_HAVE_LIBOPCODES
-  disassemble_info info;
-  INIT_DISASSEMBLE_INFO(info, stdout, fprintf);
-  info.flavour = bfd_target_unknown_flavour;
-  info.arch = bfd_arch_mips;
-  info.mach = 101; // XXX bfd_mach_mips_riscv requires modified bfd.h
-  info.endian = BFD_ENDIAN_LITTLE;
-  info.buffer = (bfd_byte*)&insn;
-  info.buffer_length = sizeof(insn);
-  info.buffer_vma = pc;
+  opcode_map.resize(buckets);
+  opcode_store.resize(instructions.size() + 1);
 
-  demand(print_insn_little_mips(pc, &info) == sizeof(insn), "disasm bug!");
-  #else
-  printf("unknown");
-  #endif
-  printf("\n");
+  size_t j = 0;
+  for (size_t b = 0, i = 0; b < buckets; b++)
+  {
+    opcode_map[b] = &opcode_store[j];
+    while (i < instructions.size() && b == (instructions[i].match & (buckets-1)))
+      opcode_store[j++] = instructions[i++];
+  }
+
+  assert(j == opcode_store.size()-1);
+  opcode_store[j].match = opcode_store[j].mask = 0;
+  opcode_store[j].rv32 = &illegal_instruction;
+  opcode_store[j].rv64 = &illegal_instruction;
+}
+
+void processor_t::register_extension(extension_t* x)
+{
+  for (auto insn : x->get_instructions())
+    register_insn(insn);
+  build_opcode_map();
+  for (auto disasm_insn : x->get_disasms())
+    disassembler->add_insn(disasm_insn);
+  if (ext != NULL)
+    throw std::logic_error("only one extension may be registered");
+  ext = x;
+  x->set_processor(this);
 }