3 #define CALLSTACK_BOTTOM(ctx) \
4 (ctx->callstack_seg->end - sizeof(cell) * 5)
6 inline static void flush_icache(cell start, cell len) {}
8 // In the instruction sequence:
13 // the offset from the immediate operand to MOV to the instruction after
14 // the jump is a cell for the immediate operand, 4 bytes for the JMP
15 // destination, and one byte for the JMP opcode.
16 static const fixnum xt_tail_pic_offset = 4 + 1;
18 static const unsigned char call_opcode = 0xe8;
19 static const unsigned char jmp_opcode = 0xe9;
21 inline static unsigned char call_site_opcode(cell return_address) {
22 return *(unsigned char*)(return_address - 5);
25 inline static void check_call_site(cell return_address) {
26 unsigned char opcode = call_site_opcode(return_address);
27 FACTOR_ASSERT(opcode == call_opcode || opcode == jmp_opcode);
28 (void)opcode; // suppress warning when compiling without assertions
31 inline static void* get_call_target(cell return_address) {
32 check_call_site(return_address);
33 return (void*)(*(int*)(return_address - 4) + return_address);
36 inline static void set_call_target(cell return_address, cell target) {
37 check_call_site(return_address);
38 *(int*)(return_address - 4) = (uint32_t)(target - return_address);
41 inline static bool tail_call_site_p(cell return_address) {
42 switch (call_site_opcode(return_address)) {
53 inline static unsigned int fpu_status(unsigned int status) {
57 r |= FP_TRAP_INVALID_OPERATION;
59 r |= FP_TRAP_ZERO_DIVIDE;
61 r |= FP_TRAP_OVERFLOW;
63 r |= FP_TRAP_UNDERFLOW;