#include "common.h"
#include "config.h"
#include "sim.h"
+#include "mmu.h"
+#include "htif.h"
#include "disasm.h"
#include <cinttypes>
#include <cmath>
#include <stdexcept>
#include <algorithm>
-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)
+#undef STATE
+#define STATE state
+
+processor_t::processor_t(const char* isa, sim_t* sim, uint32_t id)
+ : sim(sim), ext(NULL), disassembler(new disassembler_t),
+ id(id), run(false), debug(false)
{
+ parse_isa_string(isa);
+
+ mmu = new mmu_t(sim, this);
+
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();
+ register_base_instructions();
}
processor_t::~processor_t()
{
+#ifdef RISCV_ENABLE_HISTOGRAM
+ if (histogram_enabled)
+ {
+ fprintf(stderr, "PC Histogram size:%zu\n", pc_histogram.size());
+ for (auto it : pc_histogram)
+ fprintf(stderr, "%0" PRIx64 " %" PRIu64 "\n", it.first, it.second);
+ }
+#endif
+
+ delete mmu;
+ delete disassembler;
}
-void state_t::reset()
+static void bad_isa_string(const char* isa)
{
- // 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;
- pc = 0x2000;
-
- // the following state is undefined upon boot-up,
- // but we zero it for determinism
- XPR.reset();
- FPR.reset();
-
- evec = 0;
- epc = 0;
- badvaddr = 0;
- cause = 0;
- pcr_k0 = 0;
- pcr_k1 = 0;
- count = 0;
- compare = 0;
- fflags = 0;
- frm = 0;
+ fprintf(stderr, "error: bad --isa option %s\n", isa);
+ abort();
+}
+void processor_t::parse_isa_string(const char* str)
+{
+ std::string lowercase, tmp;
+ for (const char *r = str; *r; r++)
+ lowercase += std::tolower(*r);
+
+ const char* p = lowercase.c_str();
+ const char* all_subsets = "imafdc";
+
+ max_xlen = 64;
+ isa = reg_t(2) << 62;
+
+ if (strncmp(p, "rv32", 4) == 0)
+ max_xlen = 32, isa = reg_t(1) << 30, p += 4;
+ else if (strncmp(p, "rv64", 4) == 0)
+ p += 4;
+ else if (strncmp(p, "rv", 2) == 0)
+ p += 2;
+
+ if (!*p) {
+ p = all_subsets;
+ } else if (*p == 'g') { // treat "G" as "IMAFD"
+ tmp = std::string("imafd") + (p+1);
+ p = &tmp[0];
+ } else if (*p != 'i') {
+ bad_isa_string(str);
+ }
+
+ isa_string = "rv" + std::to_string(max_xlen) + p;
+ isa |= 1L << ('s' - 'a'); // advertise support for supervisor mode
+
+ while (*p) {
+ isa |= 1L << (*p - 'a');
+
+ if (auto next = strchr(all_subsets, *p)) {
+ all_subsets = next + 1;
+ p++;
+ } else if (*p == 'x') {
+ const char* ext = p+1, *end = ext;
+ while (islower(*end))
+ end++;
+ register_extension(find_extension(std::string(ext, end - ext).c_str())());
+ p = end;
+ } else {
+ bad_isa_string(str);
+ }
+ }
+
+ if (supports_extension('D') && !supports_extension('F'))
+ bad_isa_string(str);
+
+ // advertise support for supervisor and user modes
+ isa |= 1L << ('s' - 'a');
+ isa |= 1L << ('u' - 'a');
+}
+
+void state_t::reset()
+{
+ memset(this, 0, sizeof(*this));
+ prv = PRV_M;
+ pc = DEFAULT_RSTVEC;
+ mtvec = DEFAULT_MTVEC;
load_reservation = -1;
}
+void processor_t::set_debug_int()
+{
+ state.dcsr.debugint = true;
+}
+
void processor_t::set_debug(bool value)
{
debug = value;
ext->set_debug(value);
}
+void processor_t::set_histogram(bool value)
+{
+ histogram_enabled = value;
+#ifndef RISCV_ENABLE_HISTOGRAM
+ if (value) {
+ fprintf(stderr, "PC Histogram support has not been properly enabled;");
+ fprintf(stderr, " please re-build the riscv-isa-run project using \"configure --enable-histogram\".\n");
+ }
+#endif
+}
+
void processor_t::reset(bool value)
{
if (run == !value)
return;
run = !value;
- state.reset(); // reset the core
- set_pcr(CSR_STATUS, state.sr);
+ state.reset();
+ set_csr(CSR_MSTATUS, state.mstatus);
if (ext)
ext->reset(); // reset the extension
}
-void processor_t::take_interrupt()
+void processor_t::raise_interrupt(reg_t which)
{
- uint32_t interrupts = (state.sr & SR_IP) >> SR_IP_SHIFT;
- interrupts &= (state.sr & SR_IM) >> SR_IM_SHIFT;
+ throw trap_t(((reg_t)1 << (max_xlen-1)) | which);
+}
- if (interrupts && (state.sr & SR_EI))
- for (int i = 0; ; i++, interrupts >>= 1)
- if (interrupts & 1)
- throw trap_t((1ULL << ((state.sr & SR_S64) ? 63 : 31)) + i);
+static int ctz(reg_t val)
+{
+ int res = 0;
+ if (val)
+ while ((val & 1) == 0)
+ val >>= 1, res++;
+ return res;
}
-void processor_t::step(size_t n)
+void processor_t::take_interrupt()
{
- if(!run)
- return;
+ reg_t pending_interrupts = state.mip & state.mie;
- size_t i = 0;
- reg_t npc = state.pc;
- mmu_t* _mmu = mmu;
+ reg_t mie = get_field(state.mstatus, MSTATUS_MIE);
+ reg_t m_enabled = state.prv < PRV_M || (state.prv == PRV_M && mie);
+ reg_t enabled_interrupts = pending_interrupts & ~state.mideleg & -m_enabled;
- try
- {
- take_interrupt();
-
- // execute_insn fetches and executes one instruction
- #define execute_insn(noisy) \
- do { \
- mmu_t::insn_fetch_t fetch = _mmu->load_insn(npc); \
- if(noisy) disasm(fetch.insn.insn); \
- npc = fetch.func(this, fetch.insn.insn, npc); \
- } while(0)
-
-
- // special execute_insn for commit log dumping
-#ifdef RISCV_ENABLE_COMMITLOG
- //static disassembler disasmblr;
- #undef execute_insn
- #define execute_insn(noisy) \
- do { \
- mmu_t::insn_fetch_t fetch = _mmu->load_insn(npc); \
- if(noisy) disasm(fetch.insn.insn); \
- bool in_spvr = state.sr & SR_S; \
- if (!in_spvr) fprintf(stderr, "\n0x%016" PRIx64 " (0x%08" PRIx32 ") ", npc, fetch.insn.insn.bits()); \
- /*if (!in_spvr) fprintf(stderr, "\n0x%016" PRIx64 " (0x%08" PRIx32 ") %s ", npc, fetch.insn.insn.bits(), disasmblr.disassemble(fetch.insn.insn).c_str());*/ \
- npc = fetch.func(this, fetch.insn.insn, npc); \
- } while(0)
-#endif
+ reg_t sie = get_field(state.mstatus, MSTATUS_SIE);
+ reg_t s_enabled = state.prv < PRV_S || (state.prv == PRV_S && sie);
+ enabled_interrupts |= pending_interrupts & state.mideleg & -s_enabled;
- if(debug) for( ; i < n; i++) // print out instructions as we go
- execute_insn(true);
- else
- {
- // unrolled for speed
- for( ; n > 3 && i < n-3; i+=4)
- {
- execute_insn(false);
- execute_insn(false);
- execute_insn(false);
- execute_insn(false);
- }
- for( ; i < n; i++)
- execute_insn(false);
- }
+ if (enabled_interrupts)
+ raise_interrupt(ctz(enabled_interrupts));
+}
- state.pc = npc;
- }
- catch(trap_t& t)
- {
- take_trap(npc, t);
- }
+static bool validate_priv(reg_t priv)
+{
+ return priv == PRV_U || priv == PRV_S || priv == PRV_M;
+}
- // update timer and possibly register a timer interrupt
- uint32_t old_count = state.count;
- state.count += i;
- if(old_count < state.compare && uint64_t(old_count) + i >= state.compare)
- set_interrupt(IRQ_TIMER, true);
+void processor_t::set_privilege(reg_t prv)
+{
+ assert(validate_priv(prv));
+ mmu->flush_tlb();
+ state.prv = prv;
}
-void processor_t::take_trap(reg_t pc, trap_t& t)
+void processor_t::enter_debug_mode(uint8_t cause)
+{
+ state.dcsr.cause = cause;
+ state.dpc = state.pc;
+ state.pc = DEBUG_ROM_ENTRY;
+}
+
+void 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(), pc);
+ 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));
+ if (t.cause() == CAUSE_BREAKPOINT &&
+ sim->gdbserver && sim->gdbserver->connected()) {
+ enter_debug_mode(DCSR_CAUSE_SWBP);
+ return;
+ }
- yield_load_reservation();
- state.cause = t.cause();
- state.epc = pc;
- state.pc = state.evec;
+ // by default, trap to M-mode, unless delegated to S-mode
+ reg_t bit = t.cause();
+ reg_t deleg = state.medeleg;
+ if (bit & ((reg_t)1 << (max_xlen-1)))
+ deleg = state.mideleg, bit &= ~((reg_t)1 << (max_xlen-1));
+ if (state.prv <= PRV_S && bit < max_xlen && ((deleg >> bit) & 1)) {
+ // handle the trap in S-mode
+ state.pc = state.stvec;
+ state.scause = t.cause();
+ state.sepc = epc;
+ if (t.has_badaddr())
+ state.sbadaddr = t.get_badaddr();
+
+ reg_t s = state.mstatus;
+ s = set_field(s, MSTATUS_SPIE, get_field(s, MSTATUS_UIE << state.prv));
+ s = set_field(s, MSTATUS_SPP, state.prv);
+ s = set_field(s, MSTATUS_SIE, 0);
+ set_csr(CSR_MSTATUS, s);
+ set_privilege(PRV_S);
+ } else {
+ state.pc = state.mtvec;
+ state.mcause = t.cause();
+ state.mepc = epc;
+ if (t.has_badaddr())
+ state.mbadaddr = t.get_badaddr();
+
+ reg_t s = state.mstatus;
+ s = set_field(s, MSTATUS_MPIE, get_field(s, MSTATUS_UIE << state.prv));
+ s = set_field(s, MSTATUS_MPP, state.prv);
+ s = set_field(s, MSTATUS_MIE, 0);
+ set_csr(CSR_MSTATUS, s);
+ set_privilege(PRV_M);
+ }
- t.side_effects(&state); // might set badvaddr etc.
+ yield_load_reservation();
}
-void processor_t::deliver_ipi()
+void processor_t::disasm(insn_t insn)
{
- if (run)
- set_pcr(CSR_CLEAR_IPI, 1);
+ 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::disasm(insn_t insn)
+static bool validate_vm(int max_xlen, reg_t vm)
{
- // the disassembler is stateless, so we share it
- fprintf(stderr, "core %3d: 0x%016" PRIx64 " (0x%08" PRIx32 ") %s\n",
- id, state.pc, insn.bits(), disassembler->disassemble(insn).c_str());
+ if (max_xlen == 64 && (vm == VM_SV39 || vm == VM_SV48))
+ return true;
+ if (max_xlen == 32 && vm == VM_SV32)
+ return true;
+ return vm == VM_MBARE;
}
-reg_t processor_t::set_pcr(int which, reg_t val)
+void processor_t::set_csr(int which, reg_t val)
{
- reg_t old_pcr = get_pcr(which);
-
+ val = zext_xlen(val);
+ reg_t delegable_ints = MIP_SSIP | MIP_STIP | MIP_SEIP | (1 << IRQ_COP);
+ reg_t all_ints = delegable_ints | MIP_MSIP | MIP_MTIP;
switch (which)
{
case CSR_FFLAGS:
+ dirty_fp_state;
state.fflags = val & (FSR_AEXC >> FSR_AEXC_SHIFT);
break;
case CSR_FRM:
+ dirty_fp_state;
state.frm = val & (FSR_RD >> FSR_RD_SHIFT);
break;
case CSR_FCSR:
+ dirty_fp_state;
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;
+ case CSR_MSTATUS: {
+ if ((val ^ state.mstatus) &
+ (MSTATUS_VM | MSTATUS_MPP | MSTATUS_MPRV | MSTATUS_PUM))
+ mmu->flush_tlb();
+
+ reg_t mask = MSTATUS_SIE | MSTATUS_SPIE | MSTATUS_MIE | MSTATUS_MPIE
+ | MSTATUS_SPP | MSTATUS_FS | MSTATUS_MPRV | MSTATUS_PUM
+ | (ext ? MSTATUS_XS : 0);
+
+ if (validate_vm(max_xlen, get_field(val, MSTATUS_VM)))
+ mask |= MSTATUS_VM;
+ if (validate_priv(get_field(val, MSTATUS_MPP)))
+ mask |= MSTATUS_MPP;
+
+ state.mstatus = (state.mstatus & ~mask) | (val & mask);
+
+ bool dirty = (state.mstatus & MSTATUS_FS) == MSTATUS_FS;
+ dirty |= (state.mstatus & MSTATUS_XS) == MSTATUS_XS;
+ if (max_xlen == 32)
+ state.mstatus = set_field(state.mstatus, MSTATUS32_SD, dirty);
+ else
+ state.mstatus = set_field(state.mstatus, MSTATUS64_SD, dirty);
+
+ // spike supports the notion of xlen < max_xlen, but current priv spec
+ // doesn't provide a mechanism to run RV32 software on an RV64 machine
+ xlen = max_xlen;
break;
- case CSR_CYCLE:
- case CSR_TIME:
- case CSR_INSTRET:
- case CSR_COUNT:
- state.count = val;
+ }
+ case CSR_MIP: {
+ reg_t mask = MIP_SSIP | MIP_STIP;
+ state.mip = (state.mip & ~mask) | (val & mask);
break;
- case CSR_COMPARE:
- set_interrupt(IRQ_TIMER, false);
- state.compare = val;
+ }
+ case CSR_MIE:
+ state.mie = (state.mie & ~all_ints) | (val & all_ints);
break;
- case CSR_PTBR:
- state.ptbr = val & ~(PGSIZE-1);
+ case CSR_MIDELEG:
+ state.mideleg = (state.mideleg & ~delegable_ints) | (val & delegable_ints);
break;
- case CSR_SEND_IPI:
- sim->send_ipi(val);
+ case CSR_MEDELEG: {
+ reg_t mask = 0;
+#define DECLARE_CAUSE(name, value) mask |= 1ULL << (value);
+#include "encoding.h"
+#undef DECLARE_CAUSE
+ state.medeleg = (state.medeleg & ~mask) | (val & mask);
break;
- case CSR_CLEAR_IPI:
- set_interrupt(IRQ_IPI, val & 1);
+ }
+ case CSR_MUCOUNTEREN:
+ state.mucounteren = val & 7;
break;
- case CSR_SUP0:
- state.pcr_k0 = val;
+ case CSR_MSCOUNTEREN:
+ state.mscounteren = val & 7;
break;
- case CSR_SUP1:
- state.pcr_k1 = val;
+ case CSR_SSTATUS: {
+ reg_t mask = SSTATUS_SIE | SSTATUS_SPIE | SSTATUS_SPP | SSTATUS_FS
+ | SSTATUS_XS | SSTATUS_PUM;
+ return set_csr(CSR_MSTATUS, (state.mstatus & ~mask) | (val & mask));
+ }
+ case CSR_SIP:
+ return set_csr(CSR_MIP,
+ (state.mip & ~state.mideleg) | (val & state.mideleg));
+ case CSR_SIE:
+ return set_csr(CSR_MIE,
+ (state.mie & ~state.mideleg) | (val & state.mideleg));
+ case CSR_SEPC: state.sepc = val; break;
+ case CSR_STVEC: state.stvec = val >> 2 << 2; break;
+ case CSR_SPTBR: state.sptbr = val; break;
+ case CSR_SSCRATCH: state.sscratch = val; break;
+ case CSR_SCAUSE: state.scause = val; break;
+ case CSR_SBADADDR: state.sbadaddr = val; break;
+ case CSR_MEPC: state.mepc = val; break;
+ case CSR_MTVEC: state.mtvec = val >> 2 << 2; break;
+ case CSR_MSCRATCH: state.mscratch = val; break;
+ case CSR_MCAUSE: state.mcause = val; break;
+ case CSR_MBADADDR: state.mbadaddr = val; break;
+ case DCSR_ADDRESS:
+ state.dcsr.prv = (val & DCSR_PRV_MASK) >> DCSR_PRV_OFFSET;
+ state.dcsr.step = (val & DCSR_STEP_MASK) >> DCSR_STEP_OFFSET;
+ // TODO: ndreset and fullreset
+ state.dcsr.ebreakm = (val & DCSR_EBREAKM_MASK) >> DCSR_EBREAKM_OFFSET;
+ state.dcsr.ebreakh = (val & DCSR_EBREAKH_MASK) >> DCSR_EBREAKH_OFFSET;
+ state.dcsr.ebreaks = (val & DCSR_EBREAKS_MASK) >> DCSR_EBREAKS_OFFSET;
+ state.dcsr.ebreaku = (val & DCSR_EBREAKU_MASK) >> DCSR_EBREAKU_OFFSET;
+ state.dcsr.halt = (val & DCSR_HALT_MASK) >> DCSR_HALT_OFFSET;
break;
- case CSR_TOHOST:
- if (state.tohost == 0)
- state.tohost = val;
+ case DPC_ADDRESS:
+ state.dpc = val;
break;
- case CSR_FROMHOST:
- set_interrupt(IRQ_HOST, val != 0);
- state.fromhost = val;
+ case DSCRATCH_ADDRESS:
+ state.dscratch = val;
break;
}
-
- return old_pcr;
}
-reg_t processor_t::get_pcr(int which)
+reg_t processor_t::get_csr(int which)
{
switch (which)
{
case CSR_FFLAGS:
+ require_fp;
+ if (!supports_extension('F'))
+ break;
return state.fflags;
case CSR_FRM:
+ require_fp;
+ if (!supports_extension('F'))
+ break;
return state.frm;
case CSR_FCSR:
+ require_fp;
+ if (!supports_extension('F'))
+ break;
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:
- return state.count;
- case CSR_COMPARE:
- return state.compare;
- case CSR_CAUSE:
- return state.cause;
- case CSR_PTBR:
- return state.ptbr;
- 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:
- return state.tohost;
- case CSR_FROMHOST:
- return state.fromhost;
- default:
- return -1;
+ case CSR_CYCLE:
+ if ((state.mucounteren >> (which & (xlen-1))) & 1)
+ return get_csr(which + (CSR_MCYCLE - CSR_CYCLE));
+ break;
+ case CSR_STIME:
+ case CSR_SINSTRET:
+ case CSR_SCYCLE:
+ if ((state.mscounteren >> (which & (xlen-1))) & 1)
+ return get_csr(which + (CSR_MCYCLE - CSR_SCYCLE));
+ break;
+ case CSR_MUCOUNTEREN: return state.mucounteren;
+ case CSR_MSCOUNTEREN: return state.mscounteren;
+ case CSR_MUCYCLE_DELTA: return 0;
+ case CSR_MUTIME_DELTA: return 0;
+ case CSR_MUINSTRET_DELTA: return 0;
+ case CSR_MSCYCLE_DELTA: return 0;
+ case CSR_MSTIME_DELTA: return 0;
+ case CSR_MSINSTRET_DELTA: return 0;
+ case CSR_MUCYCLE_DELTAH: if (xlen > 32) break; else return 0;
+ case CSR_MUTIME_DELTAH: if (xlen > 32) break; else return 0;
+ case CSR_MUINSTRET_DELTAH: if (xlen > 32) break; else return 0;
+ case CSR_MSCYCLE_DELTAH: if (xlen > 32) break; else return 0;
+ case CSR_MSTIME_DELTAH: if (xlen > 32) break; else return 0;
+ case CSR_MSINSTRET_DELTAH: if (xlen > 32) break; else return 0;
+ case CSR_MCYCLE: return state.minstret;
+ case CSR_MINSTRET: return state.minstret;
+ case CSR_MCYCLEH: if (xlen > 32) break; else return state.minstret >> 32;
+ case CSR_MINSTRETH: if (xlen > 32) break; else return state.minstret >> 32;
+ case CSR_SSTATUS: {
+ reg_t mask = SSTATUS_SIE | SSTATUS_SPIE | SSTATUS_SPP | SSTATUS_FS
+ | SSTATUS_XS | SSTATUS_PUM;
+ reg_t sstatus = state.mstatus & mask;
+ if ((sstatus & SSTATUS_FS) == SSTATUS_FS ||
+ (sstatus & SSTATUS_XS) == SSTATUS_XS)
+ sstatus |= (xlen == 32 ? SSTATUS32_SD : SSTATUS64_SD);
+ return sstatus;
+ }
+ case CSR_SIP: return state.mip & state.mideleg;
+ case CSR_SIE: return state.mie & state.mideleg;
+ case CSR_SEPC: return state.sepc;
+ case CSR_SBADADDR: return state.sbadaddr;
+ case CSR_STVEC: return state.stvec;
+ case CSR_SCAUSE:
+ if (max_xlen > xlen)
+ return state.scause | ((state.scause >> (max_xlen-1)) << (xlen-1));
+ return state.scause;
+ case CSR_SPTBR: return state.sptbr;
+ case CSR_SASID: return 0;
+ case CSR_SSCRATCH: return state.sscratch;
+ case CSR_MSTATUS: return state.mstatus;
+ case CSR_MIP: return state.mip;
+ case CSR_MIE: return state.mie;
+ case CSR_MEPC: return state.mepc;
+ case CSR_MSCRATCH: return state.mscratch;
+ case CSR_MCAUSE: return state.mcause;
+ case CSR_MBADADDR: return state.mbadaddr;
+ case CSR_MISA: return isa;
+ case CSR_MARCHID: return 0;
+ case CSR_MIMPID: return 0;
+ case CSR_MVENDORID: return 0;
+ case CSR_MHARTID: return id;
+ case CSR_MTVEC: return state.mtvec;
+ case CSR_MEDELEG: return state.medeleg;
+ case CSR_MIDELEG: return state.mideleg;
+ case DCSR_ADDRESS:
+ return
+ (1 << DCSR_XDEBUGVER_OFFSET) |
+ (0 << DCSR_HWBPCOUNT_OFFSET) |
+ (0 << DCSR_NDRESET_OFFSET) |
+ (0 << DCSR_FULLRESET_OFFSET) |
+ (state.dcsr.prv << DCSR_PRV_OFFSET) |
+ (state.dcsr.step << DCSR_STEP_OFFSET) |
+ (state.dcsr.debugint << DCSR_DEBUGINT_OFFSET) |
+ (0 << DCSR_STOPCYCLE_OFFSET) |
+ (0 << DCSR_STOPTIME_OFFSET) |
+ (state.dcsr.ebreakm << DCSR_EBREAKM_OFFSET) |
+ (state.dcsr.ebreakh << DCSR_EBREAKH_OFFSET) |
+ (state.dcsr.ebreaks << DCSR_EBREAKS_OFFSET) |
+ (state.dcsr.ebreaku << DCSR_EBREAKU_OFFSET) |
+ (state.dcsr.halt << DCSR_HALT_OFFSET) |
+ (state.dcsr.cause << DCSR_CAUSE_OFFSET);
+ case DPC_ADDRESS:
+ return state.dpc;
+ case DSCRATCH_ADDRESS:
+ return state.dscratch;
}
-}
-
-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;
+ throw trap_illegal_instruction();
}
reg_t illegal_instruction(processor_t* p, insn_t insn, reg_t pc)
insn_func_t processor_t::decode_insn(insn_t insn)
{
- size_t mask = opcode_map.size()-1;
- insn_desc_t* desc = opcode_map[insn.bits() & mask];
+ // look up opcode in hash table
+ size_t idx = insn.bits() % OPCODE_CACHE_SIZE;
+ insn_desc_t desc = opcode_cache[idx];
+
+ if (unlikely(insn.bits() != desc.match)) {
+ // fall back to linear search
+ insn_desc_t* p = &instructions[0];
+ while ((insn.bits() & p->mask) != p->match)
+ p++;
+ desc = *p;
+
+ if (p->mask != 0 && p > &instructions[0]) {
+ if (p->match != (p-1)->match && p->match != (p+1)->match) {
+ // move to front of opcode list to reduce miss penalty
+ while (--p >= &instructions[0])
+ *(p+1) = *p;
+ instructions[0] = desc;
+ }
+ }
- while ((insn.bits() & desc->mask) != desc->match)
- desc++;
+ opcode_cache[idx] = desc;
+ opcode_cache[idx].match = insn.bits();
+ }
- return rv64 ? desc->rv64 : desc->rv32;
+ return xlen == 64 ? desc.rv64 : desc.rv32;
}
void processor_t::register_insn(insn_desc_t desc)
{
- assert(desc.mask & 1);
instructions.push_back(desc);
}
void processor_t::build_opcode_map()
{
- 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;
+ if (lhs.match == rhs.match)
+ return lhs.mask > rhs.mask;
+ return lhs.match > rhs.match;
}
};
- std::sort(instructions.begin(), instructions.end(), cmp(buckets-1));
+ std::sort(instructions.begin(), instructions.end(), cmp());
- opcode_map.resize(buckets);
- opcode_store.resize(instructions.size() + 1);
-
- 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;
+ for (size_t i = 0; i < OPCODE_CACHE_SIZE; i++)
+ opcode_cache[i] = {1, 0, &illegal_instruction, &illegal_instruction};
}
void processor_t::register_extension(extension_t* x)
ext = x;
x->set_processor(this);
}
+
+void processor_t::register_base_instructions()
+{
+ #define DECLARE_INSN(name, match, mask) \
+ insn_bits_t name##_match = (match), name##_mask = (mask);
+ #include "encoding.h"
+ #undef DECLARE_INSN
+
+ #define DEFINE_INSN(name) \
+ REGISTER_INSN(this, name, name##_match, name##_mask)
+ #include "insn_list.h"
+ #undef DEFINE_INSN
+
+ register_insn({0, 0, &illegal_instruction, &illegal_instruction});
+ build_opcode_map();
+}
+
+bool processor_t::load(reg_t addr, size_t len, uint8_t* bytes)
+{
+ return false;
+}
+
+bool processor_t::store(reg_t addr, size_t len, const uint8_t* bytes)
+{
+ switch (addr)
+ {
+ case 0:
+ state.mip &= ~MIP_MSIP;
+ if (bytes[0] & 1)
+ state.mip |= MIP_MSIP;
+ return true;
+
+ default:
+ return false;
+ }
+}