diff options
| -rw-r--r-- | gcc/ChangeLog | 8 | ||||
| -rw-r--r-- | gcc/cppexp.c | 130 |
2 files changed, 76 insertions, 62 deletions
diff --git a/gcc/ChangeLog b/gcc/ChangeLog index c90dc60..95021a0 100644 --- a/gcc/ChangeLog +++ b/gcc/ChangeLog @@ -1,3 +1,11 @@ +2000-04-01 Neil Booth <NeilB@earthling.net> + + * cppexp.c: (_cpp_parse_expr): Numerical constants are pushed + within the switch statement. Binary operations break out of + the switch naturally. '(' tokens handled by forcing + immediate shift. ')' handled by forcing immediate reduce to + the previous '('. New error messages. + 2000-03-31 Geoff Keating <geoffk@cygnus.com> * config/rs6000/rs6000.c (print_operand): Don't use %l for 'low diff --git a/gcc/cppexp.c b/gcc/cppexp.c index 6a391d7..d8e646c 100644 --- a/gcc/cppexp.c +++ b/gcc/cppexp.c @@ -699,7 +699,7 @@ _cpp_parse_expr (pfile) U_CHAR flags = 0; /* Read a token */ - op = lex (pfile, skip_evaluation); + op = lex (pfile, skip_evaluation); /* See if the token is an operand, in which case go to set_value. If the token is an operator, figure out its left and right @@ -710,16 +710,29 @@ _cpp_parse_expr (pfile) case NAME: cpp_ice (pfile, "lex returns a NAME"); goto syntax_error; + case ERROR: + goto syntax_error; + default: + cpp_error (pfile, "invalid character in #if"); + goto syntax_error; + case INT: case CHAR: - goto set_value; - case 0: - lprio = 0; goto maybe_reduce; - case '+': case '-': + push_immediate: + /* Push a value onto the stack. */ if (top->flags & HAVE_VALUE) { - lprio = PLUS_PRIO; - goto binop; + cpp_error (pfile, "suspected missing binary operator in #if"); + goto syntax_error; } + top->value = op.value; + top->unsignedp = op.unsignedp; + top->flags |= HAVE_VALUE; + continue; + + case '+': case '-': + lprio = PLUS_PRIO; + if (top->flags & HAVE_VALUE) + break; if (top->flags & SIGN_QUALIFIED) { cpp_error (pfile, "more than one sign operator given"); @@ -730,24 +743,25 @@ _cpp_parse_expr (pfile) case '!': case '~': flags |= RIGHT_OPERAND_REQUIRED; rprio = UNARY_PRIO; lprio = rprio + 1; goto maybe_reduce; + case '*': case '/': case '%': - lprio = MUL_PRIO; goto binop; + lprio = MUL_PRIO; break; case '<': case '>': case LEQ: case GEQ: - lprio = LESS_PRIO; goto binop; + lprio = LESS_PRIO; break; case EQUAL: case NOTEQUAL: - lprio = EQUAL_PRIO; goto binop; + lprio = EQUAL_PRIO; break; case LSH: case RSH: - lprio = SHIFT_PRIO; goto binop; - case '&': lprio = AND_PRIO; goto binop; - case '^': lprio = XOR_PRIO; goto binop; - case '|': lprio = OR_PRIO; goto binop; - case ANDAND: lprio = ANDAND_PRIO; goto binop; - case OROR: lprio = OROR_PRIO; goto binop; + lprio = SHIFT_PRIO; break; + case '&': lprio = AND_PRIO; break; + case '^': lprio = XOR_PRIO; break; + case '|': lprio = OR_PRIO; break; + case ANDAND: lprio = ANDAND_PRIO; break; + case OROR: lprio = OROR_PRIO; break; case ',': - lprio = COMMA_PRIO; goto binop; + lprio = COMMA_PRIO; break; case '(': - lprio = PAREN_OUTER_PRIO; rprio = PAREN_INNER_PRIO; - goto maybe_reduce; + lprio = PAREN_OUTER_PRIO; rprio = PAREN_INNER_PRIO + 1; + goto skip_reduction; case ')': lprio = PAREN_INNER_PRIO; rprio = PAREN_OUTER_PRIO; flags = HAVE_VALUE; /* At least, we will have after reduction. */ @@ -758,26 +772,11 @@ _cpp_parse_expr (pfile) case '?': lprio = COND_PRIO; rprio = COND_PRIO; goto maybe_reduce; - case ERROR: - goto syntax_error; - default: - cpp_error (pfile, "invalid character in #if"); - goto syntax_error; - } - - set_value: - /* Push a value onto the stack. */ - if (top->flags & HAVE_VALUE) - { - cpp_error (pfile, "syntax error in #if"); - goto syntax_error; + case 0: + lprio = 0; goto maybe_reduce; } - top->value = op.value; - top->unsignedp = op.unsignedp; - top->flags |= HAVE_VALUE; - continue; - binop: + /* Binary operation. */ flags = LEFT_OPERAND_REQUIRED|RIGHT_OPERAND_REQUIRED; rprio = lprio + 1; @@ -953,7 +952,7 @@ _cpp_parse_expr (pfile) top->value = v2; top->unsignedp = unsigned2; break; - case '(': case '?': + case '?': cpp_error (pfile, "syntax error in #if"); goto syntax_error; case ':': @@ -979,21 +978,22 @@ _cpp_parse_expr (pfile) } break; case ')': - if (! (top[0].flags & HAVE_VALUE) - || top[0].op != '(' - || (top[-1].flags & HAVE_VALUE)) + cpp_error (pfile, "missing '(' in expression"); + goto syntax_error; + case '(': + if (op.op != ')') { - cpp_error (pfile, "mismatched parentheses in #if"); + cpp_error (pfile, "missing ')' in expression"); goto syntax_error; } - else + if (!(top[1].flags & HAVE_VALUE)) { - top--; - top->value = v1; - top->unsignedp = unsigned1; - top->flags |= HAVE_VALUE; + cpp_error (pfile, "void expression between '(' and ')'"); + goto syntax_error; } - break; + op.value = v2; + op.unsignedp = unsigned2; + goto push_immediate; default: if (ISGRAPH (top[1].op)) cpp_error (pfile, "unimplemented operator '%c'\n", top[1].op); @@ -1002,18 +1002,13 @@ _cpp_parse_expr (pfile) top[1].op); } } + if (op.op == 0) - { - if (top != stack) - cpp_ice (pfile, "unbalanced stack in #if expression"); - if (!(top->flags & HAVE_VALUE)) - cpp_error (pfile, "#if with no expression"); - result = (top->value != 0); - goto done; - } - top++; - + break; + + skip_reduction: /* Check for and handle stack overflow. */ + top++; if (top == limit) { struct operation *new_stack; @@ -1034,6 +1029,8 @@ _cpp_parse_expr (pfile) top->flags = flags; top->rprio = rprio; top->op = op.op; + + /* Handle short circuiting. */ if ((op.op == OROR && top[-1].value) || (op.op == ANDAND && !top[-1].value) || (op.op == '?' && !top[-1].value)) @@ -1048,13 +1045,22 @@ _cpp_parse_expr (pfile) skip_evaluation--; } } - syntax_error: - _cpp_skip_rest_of_line (pfile); - result = 0; - done: + + if (top != stack) + cpp_ice (pfile, "unbalanced stack in #if expression"); + if (!(top->flags & HAVE_VALUE)) + cpp_error (pfile, "#if with no expression"); + result = (top->value != 0); + + tidy_up: pfile->parsing_if_directive--; CPP_SET_WRITTEN (pfile, old_written); if (stack != init_stack) free (stack); return result; + + syntax_error: + _cpp_skip_rest_of_line (pfile); + result = 0; + goto tidy_up; } |