Add extern funcs, parameter registers, fix asm_rm RSP bug

6 files changed, 91 insertions, 39 deletions

diff --git a/include/ast.h b/include/ast.h
index 1198a98..bdab6c3 100644
--- a/include/ast.h
+++ b/include/ast.h
@@ -20,7 +20,6 @@
 
 typedef struct Ast Ast;
 typedef struct FunctionParameter FunctionParameter;
-typedef struct FunctionSignature FunctionSignature;
 typedef struct FunctionCall FunctionCall;
 typedef struct StructDecl StructDecl;
 typedef struct StructField StructField;
@@ -87,6 +86,7 @@ typedef enum {
 
 typedef struct {
     union {
+        void *data;
         LhsExpr *lhs_expr;
         FunctionSignature *func_sig;
     } value;
@@ -107,6 +107,7 @@ typedef enum {
 
 typedef struct {
     union {
+        void *data;
         LhsExpr *lhs_expr;
         FunctionParameter *func_param;
     } value;
@@ -218,6 +219,7 @@ struct LhsExpr {
     BufferView var_name;
     VariableType type;
     nullable Ast *rhs_expr;
+    u16 extern_index; /* Index to extern func, extern variable, etc; if applicable */
 };
 
 #define LHS_EXPR_IS_EXTERN(expr)    ((expr)->decl_flags & DECL_FLAG_EXTERN)
@@ -297,6 +299,8 @@ CHECK_RESULT int function_signature_init(FunctionSignature *self, ArenaAllocator
 CHECK_RESULT int function_signature_add_parameter(FunctionSignature *self, const FunctionParameter *param);
 /* Adds a copy of @return_type to the function signature return type list */
 CHECK_RESULT int function_signature_add_return_type(FunctionSignature *self, const VariableType *return_type);
+CHECK_RESULT bool function_signature_equals(FunctionSignature *self, FunctionSignature *other);
+
 void function_parameter_init(FunctionParameter *self);
 CHECK_RESULT int funcdecl_init(FunctionDecl *self, FunctionSignature *signature, Scope *parent, ArenaAllocator *allocator);
 CHECK_RESULT int funccall_init(FunctionCall *self, BufferView name, ArenaAllocator *allocator);
diff --git a/include/bytecode/bytecode.h b/include/bytecode/bytecode.h
index adad291..1e4c35d 100644
--- a/include/bytecode/bytecode.h
+++ b/include/bytecode/bytecode.h
@@ -9,48 +9,52 @@
 #include <setjmp.h>
 
 /*doc(Opcode)
-    Variable length opcodes. Sizes range from 1 to 4 bytes.
+    Variable length opcodes. Sizes range from 1 to 5 bytes.
     # Instruction formats
     Instructions can be in 7 different formats:
     1. 1 byte: Opcode(u8)
-    2. 2 bytes: Opcode(u8) + register(u8)
-    3. 3 bytes: Opcode(u8) + register(u8) + register(u8)
+    2. 2 bytes: Opcode(u8) + register(i8)
+    3. 3 bytes: Opcode(u8) + register(i8) + register(i8)
     4. 3 bytes:\
     4.1 Opcode(u8) + intermediate(u16)\
     4.2 Opcode(u8) + data(u16)\
     4.3 Opcode(u8) + offset(i16)\
-    4.4 Opcode(u8) + num_reg(u16)\
-    4.5 Opcode(u8) + register(u8) + num_args(u8)
-    5. 4 bytes: Opcode(u8) + register(u8) + register(u8) + register(u8)
+    4.4 Opcode(u8) + register(i8) + num_args(u8)
+    5. 4 bytes: Opcode(u8) + register(i8) + register(i8) + register(i8)
     6. 4 bytes:\
-    6.1 Opcode(u8) + register(u8) + offset(i16)\
-    6.2 Opcode(u8) + register(u8) + intermediate(u16)\
-    6.3 Opcode(u8) + register(u8) + data(u16)
-    7. 4 bytes: Opcode(u8) + index(u16) + num_args(u8)
+    6.1 Opcode(u8) + register(i8) + offset(i16)\
+    6.2 Opcode(u8) + register(i8) + intermediate(u16)\
+    6.3 Opcode(u8) + register(i8) + data(u16)\
+    6.4 Opcode(u8) + num_param_reg(u8) + num_local_var_reg(u16)
+    7. 5 bytes: Opcode(u8) + index(u16) + num_args(u8) + register(i8)
+    # Registers
+    Registers have a range of 128. Local variables start from register 0 and increment while parameters start from -1
+    and decrement.
 */
 typedef enum {
     AMAL_OP_NOP,         /* No operation (do nothing). This can be used for patching code */
-    AMAL_OP_SETZ,        /* setz reg             - Set register value to 0 */
-    AMAL_OP_MOV,         /* mov dst, src         - Move src register to dst register */
-    AMAL_OP_MOVI,        /* movi dst, src        - Move src intermediate to dst register */
-    AMAL_OP_MOVD,        /* movd dst, src        - Move src data to dst register */
-    AMAL_OP_ADD,         /* add dst, reg1, reg2  - Add reg1 and reg2 and put the result in dst */
-    AMAL_OP_SUB,         /* sub dst, reg1, reg2  - Substract reg2 from reg1 and put the result in dst */
-    AMAL_OP_IMUL,        /* imul dst, reg1, reg2 - Signed multiplication */
-    AMAL_OP_MUL,         /* mul dst, reg1, reg2  - Unsigned multiplication */
-    AMAL_OP_IDIV,        /* idiv dst, reg1, reg2 - Signed division */
-    AMAL_OP_DIV,         /* div dst, reg1, reg2  - Unsigned division */
-    AMAL_OP_PUSH,        /* push reg             - Push register onto stack */
-    AMAL_OP_PUSHI,       /* pushi int            - Push intermediate onto stack */
-    AMAL_OP_PUSHD,       /* pushd data           - Push data onto stack */
-    AMAL_OP_CALL,        /* call fi, num_args    - Call a function using function index (fi) and num_args arguments. fi is u16 and num_args is u8 */
-    AMAL_OP_CALLR,       /* callr reg, num_args  - Call a function using a register. Used for function pointers. num_args is u8 */
-    AMAL_OP_CMP,         /* cmp dst, reg1, reg2  - Set dst to 1 if reg1 equals reg2, otherwise set it to 0 */
-    AMAL_OP_JZ,          /* jz reg, offset       - Jump to offset if reg is zero. offset is i16 */
-    AMAL_OP_JMP,         /* jmp offset           - Unconditional jump to offset. offset is i16 */
-    AMAL_OP_RET,         /* ret reg              - Return from the function with reg result */
-    AMAL_OP_FUNC_START,  /* func_start num_reg   - Start of a function which has num_reg registers allocated. num_reg is a u16 */
-    AMAL_OP_FUNC_END     /* func_end             - End of a function. Implementation should do a ret here */
+    AMAL_OP_SETZ,        /* setz reg                                     - Set register value to 0 */
+    AMAL_OP_MOV,         /* mov dst, src                                 - Move src register to dst register */
+    AMAL_OP_MOVI,        /* movi dst, src                                - Move src intermediate to dst register */
+    AMAL_OP_MOVD,        /* movd dst, src                                - Move src data to dst register */
+    AMAL_OP_ADD,         /* add dst, reg1, reg2                          - Add reg1 and reg2 and put the result in dst */
+    AMAL_OP_SUB,         /* sub dst, reg1, reg2                          - Substract reg2 from reg1 and put the result in dst */
+    AMAL_OP_IMUL,        /* imul dst, reg1, reg2                         - Signed multiplication */
+    AMAL_OP_MUL,         /* mul dst, reg1, reg2                          - Unsigned multiplication */
+    AMAL_OP_IDIV,        /* idiv dst, reg1, reg2                         - Signed division */
+    AMAL_OP_DIV,         /* div dst, reg1, reg2                          - Unsigned division */
+    AMAL_OP_PUSH,        /* push reg                                     - Push register onto stack */
+    AMAL_OP_PUSHI,       /* pushi int                                    - Push intermediate onto stack */
+    AMAL_OP_PUSHD,       /* pushd data                                   - Push data onto stack */
+    AMAL_OP_CALL,        /* call fi, num_args, dst                       - Call a function using function index (fi) and num_args arguments. The result is stored in register dst. fi is u16 and num_args is u8 */
+    AMAL_OP_CALLR,       /* callr reg, num_args                          - Call a function using a register. Used for function pointers. num_args is u8 */
+    AMAL_OP_CALLE,       /* calle efi, num_args, dst                     - Call an extern function using extern function index (efi) and num_args arguments. The result is stored in register dst. efi is u16 and num_args is u8 */
+    AMAL_OP_CMP,         /* cmp dst, reg1, reg2                          - Set dst to 1 if reg1 equals reg2, otherwise set it to 0 */
+    AMAL_OP_JZ,          /* jz reg, offset                               - Jump to offset if reg is zero. offset is i16 */
+    AMAL_OP_JMP,         /* jmp offset                                   - Unconditional jump to offset. offset is i16 */
+    AMAL_OP_RET,         /* ret reg                                      - Return from the function with reg result */
+    AMAL_OP_FUNC_START,  /* func_start num_param_reg, num_local_var_reg  - Start of a function which has num_param_reg parameter registers allocated and num_local_var_reg local variable registers allocated. num_param_reg is u8 and num_local_var_reg is u16 */
+    AMAL_OP_FUNC_END     /* func_end                                     - End of a function. Implementation should do a ret here */
 } AmalOpcode;
 
 typedef u8 AmalOpcodeType;
diff --git a/include/defs.h b/include/defs.h
index d7f6692..8cd9d39 100644
--- a/include/defs.h
+++ b/include/defs.h
@@ -7,5 +7,6 @@ typedef struct Parser Parser;
 typedef struct Scope Scope;
 typedef struct FileScopeReference FileScopeReference;
 typedef struct FunctionDecl FunctionDecl;
+typedef struct FunctionSignature FunctionSignature;
 
 #endif
diff --git a/include/program.h b/include/program.h
index 6603c63..543b38d 100644
--- a/include/program.h
+++ b/include/program.h
@@ -2,9 +2,12 @@
 #define AMAL_PROGRAM_H
 
 #include "std/buffer.h"
+#include "std/hash_map.h"
+#include "std/arena_allocator.h"
 #include "bytecode/bytecode.h"
 #include "../executor/executor.h"
 
+/* TODO: Remove all these errors and move program decoding and execution to another process (crash sandbox) */
 #define AMAL_PROGRAM_OK 0
 #define AMAL_PROGRAM_ERR -1
 #define AMAL_PROGRAM_INVALID_HEADER -16
@@ -14,7 +17,7 @@
 #define AMAL_PROGRAM_INVALID_INTERMEDIATES_SIZE -5
 #define AMAL_PROGRAM_INVALID_STRINGS -6
 #define AMAL_PROGRAM_INVALID_STRINGS_SIZE -7
-#define AMAL_PROGRAM_STRING_ALLOC_FAILURE -8
+#define AMAL_PROGRAM_ALLOC_FAILURE -8
 #define AMAL_PROGRAM_INVALID_INSTRUCTIONS_SIZE -9
 #define AMAL_PROGRAM_INVALID_INSTRUCTION -10
 #define AMAL_PROGRAM_INSTRUCTION_INVALID_INTERMEDIATE_INDEX -11
@@ -23,6 +26,10 @@
 #define AMAL_PROGRAM_INSTRUCTION_STACK_OOM -14
 #define AMAL_PROGRAM_INSTRUCTION_ILLEGAL_JUMP_TARGET -15
 #define AMAL_PROGRAM_INVALID_FUNCTIONS -16
+#define AMAL_PROGRAM_INVALID_EXTERNAL_FUNCTIONS -17
+#define AMAL_PROGRAM_INVALID_EXTERNAL_FUNCTIONS_SIZE -18
+#define AMAL_PROGRAM_INSTRUCTION_INVALID_EXTERN_FUNC_INDEX -19
+#define AMAL_PROGRAM_NO_SUCH_EXTERNAL_FUNCTION -20
 
 #define AMAL_PROGRAM_MAGIC_NUMBER (u32)0xdec05eba
 #define AMAL_PROGRAM_MAJOR_VERSION 1
@@ -31,21 +38,36 @@
 
 #define AMAL_PROGRAM_NUM_REGISTERS 256
 
+#define AMAL_PROGRAM_ARGS_SIZE_VARARGS -1
+
+typedef struct {
+    void *func;
+    int args_byte_size; /* -1 if varargs (AMAL_PROGRAM_ARGS_SIZE_VARARGS) */
+} ProgramExternFunc;
+
 typedef struct {
     Buffer/*<...>*/ data;
     u32 *string_indices;
-    char *intermediates_start;  /* Reference inside @data */
-    char *strings_start;        /* Reference inside @data */
+    u32 *extern_func_indices;
+    u8 *intermediates_start;  /* Reference inside @data */
+    u8 *strings_start;        /* Reference inside @data */
+    u8 *extern_funcs_start;   /* Reference inside @data */
     usize read_index;
 
     u16 num_intermediates;
     u16 num_strings;
     u16 num_functions;
+    u16 num_extern_functions;
+
+    ArenaAllocator allocator; /* Owned. Used by @extern_funcs_map */
+    HashMapType(BufferView, ProgramExternFunc) extern_funcs_map;
 } amal_program;
 
 CHECK_RESULT int amal_program_init(amal_program *self);
 void amal_program_deinit(amal_program *self);
 
+CHECK_RESULT int amal_program_add_extern_func(amal_program *self, BufferView name, void *func_ptr, int args_byte_size);
+
 CHECK_RESULT int amal_program_append_bytecode(amal_program *self, Bytecode *bytecode);
 CHECK_RESULT int amal_program_run(amal_program *self);
 CHECK_RESULT int amal_program_save(amal_program *self, const char *filepath);
diff --git a/include/ssa/ssa.h b/include/ssa/ssa.h
index 21d7f40..b2c8065 100644
--- a/include/ssa/ssa.h
+++ b/include/ssa/ssa.h
@@ -8,6 +8,8 @@
 
 #include <setjmp.h>
 
+#define SSA_ERR_EXTERN_FUNC_SIG_MISMATCH -20
+
 typedef enum {
     SSA_ASSIGN_INTER,
     SSA_ASSIGN_STRING,
@@ -23,6 +25,7 @@ typedef enum {
     SSA_FUNC_END,
     SSA_PUSH,
     SSA_CALL,
+    SSA_CALL_EXTERN,
     SSA_JUMP_ZERO,
     SSA_JUMP,
     SSA_RET
@@ -41,10 +44,16 @@ typedef struct {
     SsaNumberType type;
 } SsaNumber;
 
+typedef struct {
+    FunctionSignature *func_sig;
+    BufferView name;
+} SsaExternFunc;
+
 typedef i16 JumpOffset;
-typedef u16 SsaRegister;
+typedef i16 SsaRegister;
 typedef u16 SsaIntermediateIndex;
 typedef u16 SsaStringIndex;
+typedef u16 SsaExternFuncIndex;
 typedef u16 SsaFuncIndex;
 
 typedef struct {
@@ -53,10 +62,15 @@ typedef struct {
     Buffer/*SsaNumber*/ intermediates;
     HashMapType(BufferView, SsaStringIndex) strings_map;
     Buffer/*BufferView*/ strings;
+    HashMapType(BufferView, SsaExternFuncIndex) extern_funcs_map;
+    Buffer/*SsaExternFunc*/ extern_funcs;
     SsaIntermediateIndex intermediate_counter;
     SsaStringIndex string_counter;
+    SsaExternFuncIndex extern_func_counter;
     SsaRegister reg_counter;
+    SsaRegister param_counter;
     SsaFuncIndex func_counter;
+    Parser *parser; /* Borrowed */
 } Ssa;
 
 typedef struct {
@@ -72,7 +86,8 @@ typedef struct {
 
 typedef struct {
     SsaFuncIndex func_index;
-    u16 num_registers;
+    u16 num_params_regs;
+    u16 num_local_vars_regs;
 } SsaInsFuncStart;
 
 typedef struct {
@@ -82,6 +97,12 @@ typedef struct {
 } SsaInsFuncCall;
 
 typedef struct {
+    u8 num_args;
+    SsaRegister result;
+    SsaExternFuncIndex extern_func_index;
+} SsaInsFuncCallExtern;
+
+typedef struct {
     SsaRegister condition_reg;
     JumpOffset jump_offset;
 } SsaInsJumpZero;
@@ -97,7 +118,7 @@ SsaNumber create_ssa_float(f64 value);
 SsaNumber ssa_get_intermediate(Ssa *self, SsaIntermediateIndex index);
 BufferView ssa_get_string(Ssa *self, SsaStringIndex index);
 
-CHECK_RESULT int ssa_init(Ssa *self, ArenaAllocator *allocator);
+CHECK_RESULT int ssa_init(Ssa *self, Parser *parser);
 
 typedef struct {
     jmp_buf env;
diff --git a/include/std/hash_map.h b/include/std/hash_map.h
index 020748b..d789db4 100644
--- a/include/std/hash_map.h
+++ b/include/std/hash_map.h
@@ -23,7 +23,7 @@ struct HashMap {
 
 #define HashMapType(key_type, value_type) __attribute__((annotate(#key_type", "#value_type))) HashMap
 
-CHECK_RESULT int hash_map_init(HashMap *self, ArenaAllocator *allocator, usize value_type_size, HashMapCompare compare_func, HashMapHash hash_func);
+CHECK_RESULT int hash_map_init(HashMap *self, ArenaAllocator *allocator, usize value_type_size, HashMapCompare key_compare_func, HashMapHash key_hash_func);
 /*
 Not thread-safe.
 Expected @value size to be @self->value_type_size.