factors decoder into separate component

This commit is contained in:
2022-06-19 12:45:34 +02:00
parent cb5375258a
commit f096b15dbd
8 changed files with 455 additions and 419 deletions

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@ -69,6 +69,7 @@ def getCString(def val){
#include <array>
#include <iss/arch/traits.h>
#include <iss/arch_if.h>
#include <iss/arch/instruction_decoder.h>
#include <iss/vm_if.h>
namespace iss {
@ -120,6 +121,8 @@ template <> struct traits<${coreDef.name.toLowerCase()}> {
${instr.instruction.name} = ${index},<%}%>
MAX_OPCODE
};
static std::unique_ptr<instruction_decoder<${coreDef.name.toLowerCase()}>> get_decoder();
};
struct ${coreDef.name.toLowerCase()}: public arch_if {

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@ -0,0 +1,86 @@
#include "${coreDef.name.toLowerCase()}.h"
#include <vector>
#include <array>
#include <cstdlib>
#include <algorithm>
namespace iss {
namespace arch {
namespace {
// according to
// https://stackoverflow.com/questions/8871204/count-number-of-1s-in-binary-representation
#ifdef __GCC__
constexpr size_t bit_count(uint32_t u) { return __builtin_popcount(u); }
#elif __cplusplus < 201402L
constexpr size_t uCount(uint32_t u) { return u - ((u >> 1) & 033333333333) - ((u >> 2) & 011111111111); }
constexpr size_t bit_count(uint32_t u) { return ((uCount(u) + (uCount(u) >> 3)) & 030707070707) % 63; }
#else
constexpr size_t bit_count(uint32_t u) {
size_t uCount = u - ((u >> 1) & 033333333333) - ((u >> 2) & 011111111111);
return ((uCount + (uCount >> 3)) & 030707070707) % 63;
}
#endif
using opcode_e = traits<${coreDef.name.toLowerCase()}>::opcode_e;
/****************************************************************************
* start opcode definitions
****************************************************************************/
struct instruction_desriptor {
size_t length;
uint32_t value;
uint32_t mask;
opcode_e op;
};
const std::array<instruction_desriptor, ${instructions.size}> instr_descr = {{
/* entries are: size, valid value, valid mask, function ptr */<%instructions.each{instr -> %>
{${instr.length}, ${instr.encoding}, ${instr.mask}, opcode_e::${instr.instruction.name}},<%}%>
}};
}
template<>
struct instruction_decoder<${coreDef.name.toLowerCase()}> {
using opcode_e = traits<${coreDef.name.toLowerCase()}>::opcode_e;
using code_word_t=traits<${coreDef.name.toLowerCase()}>::code_word_t;
struct instruction_pattern {
uint32_t value;
uint32_t mask;
opcode_e id;
};
std::array<std::vector<instruction_pattern>, 4> qlut;
template<typename T>
unsigned decode_instruction(T);
instruction_decoder() {
for (auto instr : instr_descr) {
auto quadrant = instr.value & 0x3;
qlut[quadrant].push_back(instruction_pattern{instr.value, instr.mask, instr.op});
}
for(auto& lut: qlut){
std::sort(std::begin(lut), std::end(lut), [](instruction_pattern const& a, instruction_pattern const& b){
return bit_count(a.mask) > bit_count(b.mask);
});
}
}
};
template<>
unsigned instruction_decoder<${coreDef.name.toLowerCase()}>::decode_instruction<traits<${coreDef.name.toLowerCase()}>::code_word_t>(traits<${coreDef.name.toLowerCase()}>::code_word_t instr){
auto res = std::find_if(std::begin(qlut[instr&0x3]), std::end(qlut[instr&0x3]), [instr](instruction_pattern const& e){
return !((instr&e.mask) ^ e.value );
});
return static_cast<unsigned>(res!=std::end(qlut[instr&0x3])? res->id : opcode_e::MAX_OPCODE);
}
std::unique_ptr<instruction_decoder<${coreDef.name.toLowerCase()}>> traits<${coreDef.name.toLowerCase()}>::get_decoder(){
return std::make_unique<instruction_decoder<${coreDef.name.toLowerCase()}>>();
}
}
}

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@ -12,5 +12,6 @@
${name}: <% instrList.findAll{!it.instruction.name.startsWith("__")}.each { %>
- ${it.instruction.name}:
encoding: ${it.encoding}
mask: ${it.mask}<%}}%>
mask: ${it.mask}<%if(it.attributes.size) {%>
attributes: ${it.attributes}<%}}}%>

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@ -73,6 +73,7 @@ public:
using addr_t = typename super::addr_t;
using reg_t = typename traits::reg_t;
using mem_type_e = typename traits::mem_type_e;
using opcode_e = typename traits::opcode_e;
vm_impl();
@ -94,7 +95,6 @@ protected:
inline const char *name(size_t index){return traits::reg_aliases.at(index);}
typename arch::traits<ARCH>::opcode_e decode_inst_id(code_word_t instr);
virt_addr_t execute_inst(finish_cond_e cond, virt_addr_t start, uint64_t icount_limit) override;
// some compile time constants
@ -111,13 +111,7 @@ protected:
std::array<compile_func, LUT_SIZE_C> lut_00, lut_01, lut_10;
std::array<compile_func, LUT_SIZE> lut_11;
struct instruction_pattern {
uint32_t value;
uint32_t mask;
typename arch::traits<ARCH>::opcode_e id;
};
std::array<std::vector<instruction_pattern>, 4> qlut;
std::unique_ptr<instruction_decoder<ARCH>> decoder;
inline void raise(uint16_t trap_id, uint16_t cause){
auto trap_val = 0x80ULL << 24 | (cause << 16) | trap_id;
@ -139,42 +133,7 @@ protected:
template<typename T>
T& pc_assign(T& val){super::ex_info.branch_taken=true; return val;}
inline uint8_t readSpace1(typename super::mem_type_e space, uint64_t addr){
auto ret = super::template read_mem<uint8_t>(space, addr);
if(this->core.trap_state) throw 0;
return ret;
}
inline uint16_t readSpace2(typename super::mem_type_e space, uint64_t addr){
auto ret = super::template read_mem<uint16_t>(space, addr);
if(this->core.trap_state) throw 0;
return ret;
}
inline uint32_t readSpace4(typename super::mem_type_e space, uint64_t addr){
auto ret = super::template read_mem<uint32_t>(space, addr);
if(this->core.trap_state) throw 0;
return ret;
}
inline uint64_t readSpace8(typename super::mem_type_e space, uint64_t addr){
auto ret = super::template read_mem<uint64_t>(space, addr);
if(this->core.trap_state) throw 0;
return ret;
}
inline void writeSpace1(typename super::mem_type_e space, uint64_t addr, uint8_t data){
super::write_mem(space, addr, data);
if(this->core.trap_state) throw 0;
}
inline void writeSpace2(typename super::mem_type_e space, uint64_t addr, uint16_t data){
super::write_mem(space, addr, data);
if(this->core.trap_state) throw 0;
}
inline void writeSpace4(typename super::mem_type_e space, uint64_t addr, uint32_t data){
super::write_mem(space, addr, data);
if(this->core.trap_state) throw 0;
}
inline void writeSpace8(typename super::mem_type_e space, uint64_t addr, uint64_t data){
super::write_mem(space, addr, data);
if(this->core.trap_state) throw 0;
}
template<unsigned W, typename U, typename S = typename std::make_signed<U>::type>
inline S sext(U from) {
auto mask = (1ULL<<W) - 1;
@ -194,20 +153,6 @@ protected:
${it}<%}%>
<%}%>
private:
/****************************************************************************
* start opcode definitions
****************************************************************************/
struct InstructionDesriptor {
size_t length;
uint32_t value;
uint32_t mask;
typename arch::traits<ARCH>::opcode_e op;
};
const std::array<InstructionDesriptor, ${instructions.size}> instr_descr = {{
/* entries are: size, valid value, valid mask, function ptr */<%instructions.each{instr -> %>
{${instr.length}, ${instr.encoding}, ${instr.mask}, arch::traits<ARCH>::opcode_e::${instr.instruction.name}},<%}%>
}};
//static constexpr typename traits::addr_t upper_bits = ~traits::PGMASK;
iss::status fetch_ins(virt_addr_t pc, uint8_t * data){
@ -247,16 +192,7 @@ constexpr size_t bit_count(uint32_t u) {
template <typename ARCH>
vm_impl<ARCH>::vm_impl(ARCH &core, unsigned core_id, unsigned cluster_id)
: vm_base<ARCH>(core, core_id, cluster_id) {
unsigned id=0;
for (auto instr : instr_descr) {
auto quadrant = instr.value & 0x3;
qlut[quadrant].push_back(instruction_pattern{instr.value, instr.mask, instr.op});
}
for(auto& lut: qlut){
std::sort(std::begin(lut), std::end(lut), [](instruction_pattern const& a, instruction_pattern const& b){
return bit_count(a.mask) > bit_count(b.mask);
});
}
decoder = traits::get_decoder();
}
inline bool is_count_limit_enabled(finish_cond_e cond){
@ -267,19 +203,11 @@ inline bool is_jump_to_self_enabled(finish_cond_e cond){
return (cond & finish_cond_e::JUMP_TO_SELF) == finish_cond_e::JUMP_TO_SELF;
}
template <typename ARCH>
typename arch::traits<ARCH>::opcode_e vm_impl<ARCH>::decode_inst_id(code_word_t instr){
for(auto& e: qlut[instr&0x3]){
if(!((instr&e.mask) ^ e.value )) return e.id;
}
return arch::traits<ARCH>::opcode_e::MAX_OPCODE;
}
template <typename ARCH>
typename vm_base<ARCH>::virt_addr_t vm_impl<ARCH>::execute_inst(finish_cond_e cond, virt_addr_t start, uint64_t icount_limit){
auto pc=start;
auto* PC = reinterpret_cast<uint32_t*>(this->regs_base_ptr+arch::traits<ARCH>::reg_byte_offsets[arch::traits<ARCH>::PC]);
auto* NEXT_PC = reinterpret_cast<uint32_t*>(this->regs_base_ptr+arch::traits<ARCH>::reg_byte_offsets[arch::traits<ARCH>::NEXT_PC]);
auto* PC = reinterpret_cast<uint32_t*>(this->regs_base_ptr+traits::reg_byte_offsets[traits::PC]);
auto* NEXT_PC = reinterpret_cast<uint32_t*>(this->regs_base_ptr+traits::reg_byte_offsets[traits::NEXT_PC]);
auto& trap_state = this->core.trap_state;
auto& icount = this->core.icount;
auto& cycle = this->core.cycle;
@ -296,11 +224,11 @@ typename vm_base<ARCH>::virt_addr_t vm_impl<ARCH>::execute_inst(finish_cond_e co
} else {
if (is_jump_to_self_enabled(cond) &&
(instr == 0x0000006f || (instr&0xffff)==0xa001)) throw simulation_stopped(0); // 'J 0' or 'C.J 0'
auto inst_id = decode_inst_id(instr);
auto inst_id = static_cast<opcode_e>(decoder->decode_instruction(instr));
// pre execution stuff
if(this->sync_exec && PRE_SYNC) this->do_sync(PRE_SYNC, static_cast<unsigned>(inst_id));
switch(inst_id){<%instructions.eachWithIndex{instr, idx -> %>
case arch::traits<ARCH>::opcode_e::${instr.name}: {
case opcode_e::${instr.name}: {
<%instr.fields.eachLine{%>${it}
<%}%>if(this->disass_enabled){
/* generate console output when executing the command */<%instr.disass.eachLine{%>
@ -308,8 +236,8 @@ typename vm_base<ARCH>::virt_addr_t vm_impl<ARCH>::execute_inst(finish_cond_e co
}
// used registers<%instr.usedVariables.each{ k,v->
if(v.isArray) {%>
auto* ${k} = reinterpret_cast<uint${nativeTypeSize(v.type.size)}_t*>(this->regs_base_ptr+arch::traits<ARCH>::reg_byte_offsets[arch::traits<ARCH>::${k}0]);<% }else{ %>
auto* ${k} = reinterpret_cast<uint${nativeTypeSize(v.type.size)}_t*>(this->regs_base_ptr+arch::traits<ARCH>::reg_byte_offsets[arch::traits<ARCH>::${k}]);
auto* ${k} = reinterpret_cast<uint${nativeTypeSize(v.type.size)}_t*>(this->regs_base_ptr+traits::reg_byte_offsets[traits::${k}0]);<% }else{ %>
auto* ${k} = reinterpret_cast<uint${nativeTypeSize(v.type.size)}_t*>(this->regs_base_ptr+traits::reg_byte_offsets[traits::${k}]);
<%}}%>// calculate next pc value
*NEXT_PC = *PC + ${instr.length/8};
// execute instruction<%instr.behavior.eachLine{%>