diff options
Diffstat (limited to 'com.c')
| -rw-r--r-- | com.c | 101 |
1 files changed, 93 insertions, 8 deletions
@@ -47,6 +47,7 @@ static int stack_effect_of(Op opcode) { case OP_SETLOCAL: case OP_RET: case OP_HALT: + case OP_ARRLEN: return 0; case OP_DROP: case OP_0BRANCH: @@ -298,15 +299,18 @@ static void end_scope(Compiler *C) { free(sc); } -static void declare_local(Compiler *C, char *name) { +// returns slot of declared local +static uint8_t declare_local(Compiler *C, char *name) { Scope *sc = C->scope; CHECK(sc != NULL, "can't declare local outside of scope"); Local *l = &sc->locals[sc->nlocals++]; l->name = name; // -1 because local is expected to be already on the stack // ie sitting just below where stack_cur points - l->slot = C->stack_cur - 1; + uint8_t slot = C->stack_cur - 1; + l->slot = slot; // printf("declaring local %s at %d, stack_cur is %d\n",l->name, l->slot, C->stack_cur); + return slot; } static Local *locate_local(Compiler *C, char *name) { for (Scope *sc = C->scope; sc != NULL; sc = sc->outer) { @@ -353,14 +357,10 @@ void for_form(Compiler *C, AstVec l, Op _, int flags) { compile_opcode(C, OP_LOADK); compile_byte(C, compile_constant(C, VAL_NUM(0))); - declare_local(C, ivar); - Local *loc = locate_local(C, ivar); - int islot = loc->slot; + uint8_t islot = declare_local(C, ivar); compile_node(C, blist.vals[1], 0); - declare_local(C, "__max__"); - loc = locate_local(C, "__max__"); - int mslot = loc->slot; + uint8_t mslot = declare_local(C, "__max__"); // A // getlocal ivar @@ -401,6 +401,90 @@ void for_form(Compiler *C, AstVec l, Op _, int flags) { end_scope(C); } +void each_form(Compiler *C, AstVec l, Op _, int flags) { + // (each (x a) ...) + // returns nil, for now + CHECK(l.vals[1].ty == AST_LIST, "each needs binding list"); + AstVec blist = l.vals[1].as.list; + CHECK(blist.len == 2, "each binding list must have length 2"); + CHECK(blist.vals[0].ty == AST_IDENT, "can only bind to ident"); + char *ivar = blist.vals[0].as.str; + + begin_scope(C); + + compile_opcode(C, OP_LOADK); + compile_byte(C, compile_constant(C, VAL_NUM(0))); + uint8_t islot = declare_local(C, "__idx__"); + + compile_node(C, blist.vals[1], 0); + uint8_t aslot = declare_local(C, "__arr__"); + + compile_opcode(C, OP_GETLOCAL); + compile_byte(C, aslot); + compile_opcode(C, OP_ARRLEN); + uint8_t mslot = declare_local(C, "__max__"); + + compile_opcode(C, OP_NIL); + uint8_t vslot = declare_local(C, ivar); + + + // A + // getlocal idx + // getlocal max + // cmp + // 0branch -> B + // getlocal arr + // getlocal idx + // call 2 + // setlocal ivar + // body ... + // incr idx + // redo -> A + // B: + // nil + + size_t dest_A = BYTECODE(C).len; + compile_opcode(C, OP_GETLOCAL); + compile_byte(C, islot); + compile_opcode(C, OP_GETLOCAL); + compile_byte(C, mslot); + compile_opcode(C, OP_CMP); + compile_opcode(C, OP_0BRANCH); + size_t ph_B = placeholder(C); + + compile_opcode(C, OP_GETLOCAL); + compile_byte(C, aslot); + compile_opcode(C, OP_GETLOCAL); + compile_byte(C, islot); + compile_call_instr(C, 2); + compile_opcode(C, OP_SETLOCAL); + compile_byte(C, vslot); + compile_opcode(C, OP_DROP); + + compile_body(C, l, 2, flags & ~F_tail); + compile_opcode(C, OP_DROP); + + compile_opcode(C, OP_GETLOCAL); + compile_byte(C, islot); + compile_opcode(C, OP_LOADK); + compile_byte(C, compile_constant(C, VAL_NUM(1))); + compile_opcode(C, OP_ADD); + compile_opcode(C, OP_SETLOCAL); + compile_byte(C, islot); + compile_opcode(C, OP_DROP); + + compile_opcode(C, OP_REDO); + size_t ph_A = placeholder(C); + + size_t dest_B = BYTECODE(C).len; + compile_opcode(C, OP_NIL); + + patch(C, ph_A, ph_A - dest_A + 2); + patch(C, ph_B, dest_B - ph_B - 2); + + end_scope(C); +} + void def_form(Compiler *C, AstVec l, Op _, int flags) { CHECK(l.vals[1].ty == AST_IDENT, "def's first argument must be ident"); @@ -459,6 +543,7 @@ static BuiltinForm builtin_forms[] = { { "if", 3, false, if_form, 0 }, { "while", 2, true, while_form, 0 }, { "for", 2, true, for_form, 0 }, + { "each", 2, true, each_form, 0 }, { "fn", 2, true, fn_form, 0 }, { "let", 2, true, let_form, 0 }, { "def", 2, false, def_form, 0 }, |