diff options
Diffstat (limited to 'i386-asm.c')
| -rw-r--r-- | i386-asm.c | 33 |
1 files changed, 33 insertions, 0 deletions
@@ -1185,6 +1185,28 @@ static const char *skip_constraint_modifiers(const char *p) return p; } +/* If T (a token) is of the form "%reg" returns the register + number and type, otherwise return -1. */ +ST_FUNC int asm_parse_regvar (int t) +{ + const char *s; + Operand op; + if (t < TOK_IDENT) + return -1; + s = table_ident[t - TOK_IDENT]->str; + if (s[0] != '%') + return -1; + t = tok_alloc(s+1, strlen(s)-1)->tok; + unget_tok(t); + unget_tok('%'); + parse_operand(tcc_state, &op); + /* Accept only integer regs for now. */ + if (op.type & OP_REG) + return op.reg; + else + return -1; +} + #define REG_OUT_MASK 0x01 #define REG_IN_MASK 0x02 @@ -1227,6 +1249,11 @@ ST_FUNC void asm_compute_constraints(ASMOperand *operands, tcc_error("cannot reference twice the same operand"); operands[k].input_index = i; op->priority = 5; + } else if ((op->vt->r & VT_VALMASK) == VT_LOCAL + && op->vt->sym + && (reg = op->vt->sym->r & VT_VALMASK) < VT_CONST) { + op->priority = 1; + op->reg = reg; } else { op->priority = constraint_priority(str); } @@ -1274,6 +1301,12 @@ ST_FUNC void asm_compute_constraints(ASMOperand *operands, } else { reg_mask = REG_IN_MASK; } + if (op->reg >= 0) { + if (is_reg_allocated(op->reg)) + tcc_error("asm regvar requests register that's taken already"); + reg = op->reg; + goto reg_found; + } try_next: c = *str++; switch(c) { |