diff options
Diffstat (limited to 'assembler/src/main.c')
| -rw-r--r-- | assembler/src/main.c | 43 |
1 files changed, 31 insertions, 12 deletions
diff --git a/assembler/src/main.c b/assembler/src/main.c index cf72b85a..4dee1b32 100644 --- a/assembler/src/main.c +++ b/assembler/src/main.c @@ -79,6 +79,16 @@ static const struct option longopts[] = { { NULL, 0, NULL, 0 } }; +// jump distance used in branch instructions as JIP or UIP +static int jump_distance(int offset) +{ + // Gen4- bspec: the jump distance is in number of sixteen-byte units + // Gen5+ bspec: the jump distance is in number of eight-byte units + if(gen_level >= 5) + offset *= 2; + return offset; +} + static void usage(void) { fprintf(stderr, "usage: intel-gen4asm [options] inputfile\n"); @@ -169,6 +179,10 @@ int label_to_addr(char *name, int start_addr) r = p->addr; } } + if(r == -1) { + fprintf(stderr, "Can't find label %s\n", name); + exit(1); + } return r; } @@ -385,20 +399,25 @@ int main(int argc, char **argv) } for (entry = compiled_program.first; entry; entry = entry->next) { - if (entry->instruction.first_reloc_target) { - int addr = label_to_addr(entry->instruction.first_reloc_target, - entry->inst_offset); - if(addr == -1) { - fprintf(stderr, "can not find label %s\n", - entry->instruction.first_reloc_target); - exit(1); - } - int offset = addr - entry->inst_offset; + struct brw_instruction *inst = & entry->instruction; + + if (inst->first_reloc_target) + inst->first_reloc_offset = label_to_addr(inst->first_reloc_target, entry->inst_offset); + + if (inst->second_reloc_target) + inst->second_reloc_offset = label_to_addr(inst->second_reloc_target, entry->inst_offset); + + if (inst->second_reloc_offset) { + // this is a branch instruction with two offset arguments + entry->instruction.bits3.branch_2_offset.JIP = jump_distance(inst->first_reloc_offset - entry->inst_offset); + entry->instruction.bits3.branch_2_offset.UIP = jump_distance(inst->second_reloc_offset - entry->inst_offset); + } else if (inst->first_reloc_offset) { + // this is a branch instruction with one offset argument + int offset = inst->first_reloc_offset - entry->inst_offset; + /* bspec: Unlike other flow control instructions, the offset used by JMPI is relative to the incremented instruction pointer rather than the IP value for the instruction itself. */ if(entry->instruction.header.opcode == BRW_OPCODE_JMPI) offset --; - if(gen_level >= 5) - offset *= 2; // bspec: the jump distance in number of eight-byte units - entry->instruction.bits3.JIP = offset; + entry->instruction.bits3.JIP = jump_distance(offset); if(entry->instruction.header.opcode == BRW_OPCODE_ELSE) entry->instruction.bits3.branch_2_offset.UIP = 1; } |