3 inline static void* frame_return_address(void* frame_top) {
4 return *(void**)frame_top;
7 inline static void set_frame_return_address(void* frame_top,
8 void* return_address) {
9 *(void**)frame_top = return_address;
12 #define CALLSTACK_BOTTOM(ctx) \
13 (void*)(ctx->callstack_seg->end - sizeof(cell) * 5)
15 inline static void flush_icache(cell start, cell len) {}
17 /* In the instruction sequence:
22 the offset from the immediate operand to MOV to the instruction after
23 the jump is a cell for the immediate operand, 4 bytes for the JMP
24 destination, and one byte for the JMP opcode. */
25 static const fixnum xt_tail_pic_offset = 4 + 1;
27 static const unsigned char call_opcode = 0xe8;
28 static const unsigned char jmp_opcode = 0xe9;
30 inline static unsigned char call_site_opcode(cell return_address) {
31 return *(unsigned char*)(return_address - 5);
34 inline static void check_call_site(cell return_address) {
35 unsigned char opcode = call_site_opcode(return_address);
36 FACTOR_ASSERT(opcode == call_opcode || opcode == jmp_opcode);
37 (void)opcode; // suppress warning when compiling without assertions
40 inline static void* get_call_target(cell return_address) {
41 check_call_site(return_address);
42 return (void*)(*(int*)(return_address - 4) + return_address);
45 inline static void set_call_target(cell return_address, void* target) {
46 check_call_site(return_address);
47 *(int*)(return_address - 4) = (uint32_t)((cell)target - return_address);
50 inline static bool tail_call_site_p(cell return_address) {
51 switch (call_site_opcode(return_address)) {
62 inline static unsigned int fpu_status(unsigned int status) {
66 r |= FP_TRAP_INVALID_OPERATION;
68 r |= FP_TRAP_ZERO_DIVIDE;
70 r |= FP_TRAP_OVERFLOW;
72 r |= FP_TRAP_UNDERFLOW;