From 53aed3fadf1f7ad66dea9a8a0b46bf42eda921be Mon Sep 17 00:00:00 2001 From: hachem Date: Mon, 31 Aug 2026 16:56:40 +0200 Subject: feat: add memory loads via ^reg --- src/codegen/nasm.c | 44 +++++++++++++++++++++++++++++++++++++++++--- src/parser/ast.c | 3 +++ src/parser/ast.h | 26 +++++++++++++++++--------- src/parser/parser.c | 41 ++++++++++++++++++++++++++++------------- src/sema/sema.c | 13 +++++++++++++ 5 files changed, 102 insertions(+), 25 deletions(-) (limited to 'src') diff --git a/src/codegen/nasm.c b/src/codegen/nasm.c index e55c791..2f8de80 100644 --- a/src/codegen/nasm.c +++ b/src/codegen/nasm.c @@ -203,6 +203,7 @@ static bool emit_operand(struct Emitter* emitter, struct Expr* expr) return true; } case EXPR_BINARY: + case EXPR_DEREF: return false; } @@ -248,6 +249,7 @@ static bool expr_supported(struct Emitter* emitter, struct Expr* expr) { case EXPR_PRIMARY: case EXPR_MEMBER: + case EXPR_DEREF: return true; case EXPR_BINARY: if (expr->binary.right->kind != EXPR_PRIMARY && @@ -262,8 +264,41 @@ static bool expr_supported(struct Emitter* emitter, struct Expr* expr) return false; } +// dst = [address], zero-extending narrower loads into the full register +static void emit_load(struct Emitter* emitter, const char* dst, struct DerefExpr* deref) +{ + FILE* out = emitter->out; + switch (deref->size) + { + case STORE_SIZE_BYTE: + fprintf(out, "\tmovzx %s, byte [", dst); + break; + case STORE_SIZE_WORD: + fprintf(out, "\tmovzx %s, word [", dst); + break; + case STORE_SIZE_DWORD: + { + const char* dword = sized_register(text_token(dst), STORE_SIZE_DWORD); + fprintf(out, "\tmov %s, [", dword != NULL ? dword : dst); + break; + } + default: + fprintf(out, "\tmov %s, [", dst); + break; + } + + emit_operand(emitter, deref->address); + fprintf(out, "]\n"); +} + static void emit_expr_into(struct Emitter* emitter, const char* dst, struct Expr* expr) { + if (expr->kind == EXPR_DEREF) + { + emit_load(emitter, dst, &expr->deref); + return; + } + if (expr->kind == EXPR_BINARY) { emit_expr_into(emitter, dst, expr->binary.left); @@ -389,7 +424,8 @@ static void emit_assign(struct Emitter* emitter, struct AssignStatement* assign) const char* mnemonic = assign_mnemonic(assign->op.type); bool value_is_buffer = assign->value->kind == EXPR_PRIMARY && is_buffer_name(emitter, assign->value->primary.token); - if (mnemonic == NULL || assign->value->kind == EXPR_BINARY || value_is_buffer) + if (mnemonic == NULL || assign->value->kind == EXPR_BINARY + || assign->value->kind == EXPR_DEREF || value_is_buffer) { fprintf(emitter->out, "\t; TODO: unsupported assignment\n"); return; @@ -458,7 +494,7 @@ static void emit_call(struct Emitter* emitter, struct CallStatement* call) for (size_t i = 0; i < call->arg_count; i += 1) { - if (call->args[i]->kind == EXPR_BINARY) + if (call->args[i]->kind == EXPR_BINARY || call->args[i]->kind == EXPR_DEREF) { fprintf(emitter->out, "\t; TODO: unsupported call argument\n"); continue; @@ -478,7 +514,9 @@ static void emit_statement(struct Emitter* emitter, struct Statement* statement) static void emit_if(struct Emitter* emitter, struct IfStatement* branch) { const char* jump = jump_if_false(branch->comparison.type); - if (jump == NULL || branch->left->kind == EXPR_BINARY || branch->right->kind == EXPR_BINARY) + if (jump == NULL + || branch->left->kind == EXPR_BINARY || branch->left->kind == EXPR_DEREF + || branch->right->kind == EXPR_BINARY || branch->right->kind == EXPR_DEREF) { fprintf(emitter->out, "\t; TODO: unsupported if\n"); return; diff --git a/src/parser/ast.c b/src/parser/ast.c index 96ee479..f9f857d 100644 --- a/src/parser/ast.c +++ b/src/parser/ast.c @@ -18,6 +18,9 @@ void free_expr(struct Expr* expr) case EXPR_MEMBER: free_expr(expr->member.object); break; + case EXPR_DEREF: + free_expr(expr->deref.address); + break; } free(expr); diff --git a/src/parser/ast.h b/src/parser/ast.h index a98f43b..fc7af2b 100644 --- a/src/parser/ast.h +++ b/src/parser/ast.h @@ -24,11 +24,21 @@ struct Param struct Token reg; }; +enum StoreSize +{ + STORE_SIZE_NONE, + STORE_SIZE_BYTE, + STORE_SIZE_WORD, + STORE_SIZE_DWORD, + STORE_SIZE_QWORD, +}; + enum ExprKind { EXPR_PRIMARY, EXPR_BINARY, EXPR_MEMBER, + EXPR_DEREF, }; struct PrimaryExpr @@ -49,6 +59,12 @@ struct MemberExpr struct Token member; }; +struct DerefExpr +{ + enum StoreSize size; + struct Expr* address; +}; + struct Expr { enum ExprKind kind; @@ -57,18 +73,10 @@ struct Expr struct PrimaryExpr primary; struct BinaryExpr binary; struct MemberExpr member; + struct DerefExpr deref; }; }; -enum StoreSize -{ - STORE_SIZE_NONE, - STORE_SIZE_BYTE, - STORE_SIZE_WORD, - STORE_SIZE_DWORD, - STORE_SIZE_QWORD, -}; - enum StatementKind { STATEMENT_ASSIGN, diff --git a/src/parser/parser.c b/src/parser/parser.c index beb6b04..969ed86 100644 --- a/src/parser/parser.c +++ b/src/parser/parser.c @@ -133,8 +133,35 @@ static struct Expr* alloc_expr(enum ExprKind kind) return expr; } +static enum StoreSize parse_store_size(struct Parser* parser) +{ + if (match_token(parser, TOKEN_BYTE)) + return STORE_SIZE_BYTE; + if (match_token(parser, TOKEN_WORD)) + return STORE_SIZE_WORD; + if (match_token(parser, TOKEN_DWORD)) + return STORE_SIZE_DWORD; + if (match_token(parser, TOKEN_QWORD)) + return STORE_SIZE_QWORD; + return STORE_SIZE_NONE; +} + static struct Expr* parse_primary(struct Parser* parser) { + if (match_token(parser, TOKEN_CARET)) + { + enum StoreSize size = parse_store_size(parser); + + struct Expr* address = parse_primary(parser); + if (address == NULL) + return NULL; + + struct Expr* deref = alloc_expr(EXPR_DEREF); + deref->deref.size = size; + deref->deref.address = address; + return deref; + } + if (check(parser, TOKEN_IDENTIFIER) || check(parser, TOKEN_INTEGER) || check(parser, TOKEN_CHAR)) { advance_parser(parser); @@ -350,19 +377,7 @@ static bool parse_statement(struct Parser* parser, struct Statement* out) } bool deref = match_token(parser, TOKEN_CARET); - - enum StoreSize store_size = STORE_SIZE_NONE; - if (deref) - { - if (match_token(parser, TOKEN_BYTE)) - store_size = STORE_SIZE_BYTE; - else if (match_token(parser, TOKEN_WORD)) - store_size = STORE_SIZE_WORD; - else if (match_token(parser, TOKEN_DWORD)) - store_size = STORE_SIZE_DWORD; - else if (match_token(parser, TOKEN_QWORD)) - store_size = STORE_SIZE_QWORD; - } + enum StoreSize store_size = deref ? parse_store_size(parser) : STORE_SIZE_NONE; if (!consume(parser, TOKEN_IDENTIFIER, "expected a statement")) return false; diff --git a/src/sema/sema.c b/src/sema/sema.c index ad2b12a..fb53bbf 100644 --- a/src/sema/sema.c +++ b/src/sema/sema.c @@ -227,6 +227,19 @@ static void check_expr(struct RefCheck* check, struct Expr* expr) check_expr(check, expr->binary.left); check_expr(check, expr->binary.right); break; + case EXPR_DEREF: + { + struct Expr* address = expr->deref.address; + if (address->kind == EXPR_PRIMARY + && (is_register(check, address->primary.token) || is_param(check, address->primary.token))) + break; + + if (address->kind == EXPR_PRIMARY) + ref_error(check, address->primary.token, "dereference address must be a register"); + else + check_expr(check, address); + break; + } case EXPR_MEMBER: { struct Expr* object = expr->member.object; -- cgit v1.3