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reduce casting

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llvm
Clyne 3 weeks ago
parent b29adddef9
commit e887550e77
Signed by: clyne
GPG Key ID: 7BA5A2980566A649
1 changed files with 51 additions and 36 deletions
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87
sforth/forth.hpp
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@ -32,6 +32,12 @@ extern bool sforth_debug_hook();
namespace sforth {
template<typename T>
concept CellSized = (sizeof(cell) == sizeof(T));
template<typename T>
concept CellConvertible = !std::same_as<cell, T> && CellSized<T>;
constexpr bool enable_exceptions = true;
constexpr bool enable_debugger = false;
@ -87,7 +93,7 @@ template<> struct catcher<false> {
std::jmp_buf buf = {};
void operator()(error e) {
std::longjmp(buf, static_cast<int>(e));
std::longjmp(buf, std::to_underlying(e));
}
std::optional<error> set() {
@ -117,13 +123,17 @@ struct forth : public word_list
}
}
void push(cell v) {
void push1(cell v) {
assert<error::stack_overflow>(sp != dstack.begin());
*--sp = v;
}
void push(cell v, auto... vs) {
push(v); (push(vs), ...);
void push1(CellConvertible auto v) {
push1(std::bit_cast<cell>(v));
}
void push(auto v, auto... vs) {
push1(v); (push(vs), ...);
}
void rpush(func *v) {
@ -131,14 +141,16 @@ struct forth : public word_list
*--rp = v;
}
cell& top() {
template<typename T = cell>
T& top() {
assert<error::stack_underflow>(sp != dstack.end());
return *sp;
return *std::bit_cast<T*>(sp);
}
cell pop() {
template<typename T = cell>
T pop() {
assert<error::stack_underflow>(sp != dstack.end());
return *sp++;
return std::bit_cast<T>(*sp++);
}
auto rpop() -> func * {
@ -146,6 +158,10 @@ struct forth : public word_list
return *rp++;
}
void comma(CellSized auto v) {
*here++ = std::bit_cast<cell>(v);
}
auto begin_def(std::string_view name) -> word_base * {
const auto namesz = (name.size() + 1 + sizeof(cell) - 1) & ~(sizeof(cell) - 1);
const auto size = (sizeof(word_base) + namesz) / sizeof(cell);
@ -188,7 +204,7 @@ struct forth : public word_list
auto body = (*ent)->body();
if (compiling && ((*ent)->flags_len & word_base::immediate) == 0)
*here++ = std::bit_cast<cell>(body);
comma(body);
else
execute(body);
}
@ -248,8 +264,7 @@ constexpr auto initialize()
constexpr static func comma = [](auto) { *fthp->here++ = fthp->pop(); };
constexpr static func lit_impl = [](auto) {
auto ptr = std::bit_cast<cell *>(++fthp->ip);
fthp->push(*ptr);
fthp->push(*++fthp->ip);
};
constexpr static func jmp_impl = [](auto){
@ -264,7 +279,7 @@ constexpr auto initialize()
};
constexpr static auto& dict1 = native_dict<
S{"_D" }, [](auto) { fthp->push(std::bit_cast<cell>(fthp)); }, 0
S{"_D" }, [](auto) { fthp->push(fthp); }, 0
, S{"DEPTH"}, [](auto) { fthp->push(std::distance(fthp->sp, fthp->dstack.end())); }, 0
, S{"UNUSED"}, [](auto) { fthp->push(sizeof(cell) * std::distance(fthp->here, fthp->dict.end())); }, 0
, S{"_LIT" }, lit_impl, 0 // required by parser
@ -280,48 +295,48 @@ constexpr auto initialize()
, S{"LSHIFT"}, [](auto) { fthp->top() <<= fthp->pop(); }, 0
, S{"RSHIFT"}, [](auto) {
const auto shift = fthp->pop();
fthp->push(static_cast<addr>(fthp->pop()) >> shift); }, 0
fthp->push(fthp->template pop<addr>() >> shift); }, 0
, S{"M*" }, [](auto) {
dcell a = fthp->pop();
a *= fthp->pop();
fthp->push(a, a >> (8 * sizeof(cell))); }, 0
, S{"UM*" }, [](auto) {
daddr a = std::bit_cast<addr>(fthp->pop());
a *= std::bit_cast<addr>(fthp->pop());
daddr a = fthp->template pop<addr>();
a *= fthp->template pop<addr>();
fthp->push(a, a >> (8 * sizeof(addr))); }, 0
, S{"LITERAL"}, [](auto x) {
if (fthp->compiling) {
*fthp->here++ = std::bit_cast<cell>(&lit_impl);
*fthp->here++ = fthp->pop();
fthp->comma(&lit_impl);
fthp->comma(fthp->pop());
} else {
lit_impl(x);
} }, word_base::immediate
, S{"@" }, [](auto) { fthp->top() = *std::bit_cast<cell *>(fthp->top()); }, 0
, S{"!" }, [](auto) { auto p = fthp->pop(); *std::bit_cast<cell *>(p) = fthp->pop(); }, 0
, S{"C@" }, [](auto) { fthp->top() = *std::bit_cast<char *>(fthp->top()); }, 0
, S{"C!" }, [](auto) { auto p = fthp->pop(); *std::bit_cast<char *>(p) = fthp->pop(); }, 0
, S{"@" }, [](auto) { fthp->top() = *fthp->template top<cell *>(); }, 0
, S{"!" }, [](auto) { auto p = fthp->template pop<cell *>(); *p = fthp->pop(); }, 0
, S{"C@" }, [](auto) { fthp->top() = *fthp->template top<char *>(); }, 0
, S{"C!" }, [](auto) { auto p = fthp->template pop<char *>(); *p = fthp->pop(); }, 0
, S{"=" }, [](auto) { auto v = fthp->pop(); fthp->top() = -(fthp->top() == v); }, 0
, S{"<" }, [](auto) { auto v = fthp->pop(); fthp->top() = -(fthp->top() < v); }, 0
, S{"U<" }, [](auto) {
addr v = fthp->pop();
addr w = fthp->pop();
const auto v = fthp->template pop<addr>();
const auto w = fthp->template pop<addr>();
fthp->push(-(w < v)); }, 0
, S{":" }, [](auto) {
auto w = fthp->parse();
auto d = std::bit_cast<func *>(fthp->begin_def(w));
fthp->rpush(d);
*fthp->here++ = std::bit_cast<cell>(prologue); }, 0
fthp->comma(prologue); }, 0
, S{"CELL" }, [](auto) { fthp->push(sizeof(cell)); }, 0
, S{"_JMP" }, [](auto) { fthp->push(std::bit_cast<cell>(&jmp_impl)); }, 0
, S{"_JMP0"}, [](auto) { fthp->push(std::bit_cast<cell>(&jmp0_impl)); }, 0
, S{"_JMP" }, [](auto) { fthp->push(&jmp_impl); }, 0
, S{"_JMP0"}, [](auto) { fthp->push(&jmp0_impl); }, 0
, S{"_PARSE"}, [](auto) {
auto w = fthp->parse();
fthp->push(std::bit_cast<cell>(w.data()), w.size()); }, 0
fthp->push(w.data(), w.size()); }, 0
, S{"_GET"}, [](auto) {
const addr u = fthp->pop();
const auto caddr = std::bit_cast<const char *>(fthp->pop());
const auto u = fthp->template pop<addr>();
const auto caddr = fthp->template pop<const char *>();
auto g = fthp->get({caddr, u});
fthp->push(g.has_value() ? std::bit_cast<cell>(*g) : 0); }, 0
fthp->push(g.has_value() ? *g : nullptr); }, 0
, S{"POSTPONE"}, [](auto) {
fthp->template assert<error::compile_only_word>(fthp->compiling);
auto w = fthp->parse();
@ -329,11 +344,11 @@ constexpr auto initialize()
fthp->template assert<error::word_not_found>(g.has_value());
if ((*g)->is_immediate()) {
*fthp->here++ = std::bit_cast<cell>((*g)->body());
fthp->comma((*g)->body());
} else {
*fthp->here++ = std::bit_cast<cell>(&lit_impl);
*fthp->here++ = std::bit_cast<cell>((*g)->body());
*fthp->here++ = std::bit_cast<cell>(&comma);
fthp->comma(&lit_impl);
fthp->comma((*g)->body());
fthp->comma(&comma);
} }, word_base::immediate
, S{"KEY"}, [](auto) {
if (fthp->sourcei != std::string_view::npos)
@ -341,8 +356,8 @@ constexpr auto initialize()
else
fthp->push(0); }, 0
, S{"_eval"}, [](auto) {
const addr u = fthp->pop();
const auto caddr = std::bit_cast<const char *>(fthp->pop());
const auto u = fthp->template pop<addr>();
const auto caddr = fthp->template pop<const char *>();
fthp->parse_line({caddr, u}); }, 0
>::word;

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