1*59d23892Sdist /* 2*59d23892Sdist * Copyright (c) 1980 Regents of the University of California. 3*59d23892Sdist * All rights reserved. The Berkeley software License Agreement 4*59d23892Sdist * specifies the terms and conditions for redistribution. 5*59d23892Sdist */ 6c9677cbaSlinton 7*59d23892Sdist #ifndef lint 8*59d23892Sdist static char sccsid[] = "@(#)predicates.c 5.1 (Berkeley) 06/06/85"; 9*59d23892Sdist #endif not lint 10c9677cbaSlinton /* 11c9677cbaSlinton * The basic tests on a symbol. 12c9677cbaSlinton */ 13c9677cbaSlinton 14c9677cbaSlinton #include "defs.h" 15c9677cbaSlinton #include "sym.h" 16c9677cbaSlinton #include "symtab.h" 175aa7b387Slinton #include "btypes.h" 18c9677cbaSlinton #include "classes.h" 19c9677cbaSlinton #include "sym.rep" 20c9677cbaSlinton 21c9677cbaSlinton /* 22c9677cbaSlinton * Test if a symbol is a parameter. This is true if there 23c9677cbaSlinton * is a cycle from s->func to s via chain pointers. 24c9677cbaSlinton */ 25c9677cbaSlinton 26c9677cbaSlinton BOOLEAN isparam(s) 27c9677cbaSlinton SYM *s; 28c9677cbaSlinton { 29c9677cbaSlinton register SYM *t; 30c9677cbaSlinton 31c9677cbaSlinton for (t = s->func; t != NIL; t = t->chain) { 32c9677cbaSlinton if (t == s) { 33c9677cbaSlinton return(TRUE); 34c9677cbaSlinton } 35c9677cbaSlinton } 36c9677cbaSlinton return(FALSE); 37c9677cbaSlinton } 38c9677cbaSlinton 39c9677cbaSlinton /* 40c9677cbaSlinton * Test if a symbol is a var parameter, i.e. has class REF. 41c9677cbaSlinton */ 42c9677cbaSlinton 43c9677cbaSlinton BOOLEAN isvarparam(s) 44c9677cbaSlinton SYM *s; 45c9677cbaSlinton { 46c9677cbaSlinton return (BOOLEAN) s->class == REF; 47c9677cbaSlinton } 48c9677cbaSlinton 49c9677cbaSlinton /* 504f2e96f3Slinton * Test if a symbol is a variable (actually any addressible quantity 514f2e96f3Slinton * with do). 524f2e96f3Slinton */ 534f2e96f3Slinton 544f2e96f3Slinton BOOLEAN isvariable(s) 554f2e96f3Slinton SYM *s; 564f2e96f3Slinton { 574f2e96f3Slinton return s->class == VAR || s->class == FVAR || s->class == REF; 584f2e96f3Slinton } 594f2e96f3Slinton 604f2e96f3Slinton /* 61c9677cbaSlinton * Test if a symbol is a block, e.g. function, procedure, or the 62c9677cbaSlinton * main program. 63c9677cbaSlinton */ 64c9677cbaSlinton 65c9677cbaSlinton BOOLEAN isblock(s) 66c9677cbaSlinton register SYM *s; 67c9677cbaSlinton { 68c9677cbaSlinton return(s->class == FUNC || s->class == PROC || s->class == PROG); 69c9677cbaSlinton } 70c9677cbaSlinton 71c9677cbaSlinton /* 72c9677cbaSlinton * Test if a symbol is builtin, that is, a predefined type or 73c9677cbaSlinton * reserved word. 74c9677cbaSlinton */ 75c9677cbaSlinton 76c9677cbaSlinton BOOLEAN isbuiltin(s) 77c9677cbaSlinton SYM *s; 78c9677cbaSlinton { 79c9677cbaSlinton return(s->blkno == 0 && s->class != PROG && s->class != VAR); 80c9677cbaSlinton } 81c9677cbaSlinton 82c9677cbaSlinton /* 83c9677cbaSlinton * Compatible tests if two types are compatible. The issue 84c9677cbaSlinton * is complicated a bit by ranges. 85c9677cbaSlinton * 86c9677cbaSlinton * Integers and reals are not compatible since they cannot always be mixed. 87c9677cbaSlinton */ 88c9677cbaSlinton 89c9677cbaSlinton BOOLEAN compatible(t1, t2) 90c9677cbaSlinton register SYM *t1, *t2; 91c9677cbaSlinton { 9267ed027bSlinton register BOOLEAN b; 9367ed027bSlinton 9467ed027bSlinton if (isvariable(t1)) { 9567ed027bSlinton t1 = t1->type; 96c9677cbaSlinton } 9767ed027bSlinton if (isvariable(t2)) { 9867ed027bSlinton t2 = t2->type; 9967ed027bSlinton } 10067ed027bSlinton if (t1 == t2) { 10167ed027bSlinton b = TRUE; 10267ed027bSlinton } else { 103c9677cbaSlinton t1 = rtype(t1); 104c9677cbaSlinton t2 = rtype(t2); 105c9677cbaSlinton if (t1->type == t2->type) { 106c9677cbaSlinton if (t1->class == RANGE && t2->class == RANGE) { 10767ed027bSlinton b = TRUE; 10867ed027bSlinton } else if ((t1->class == SCAL || t1->class == CONST) && 109c9677cbaSlinton (t2->class == SCAL || t2->class == CONST)) { 11067ed027bSlinton b = TRUE; 11167ed027bSlinton } else if (t1->type == t_char && 11267ed027bSlinton t1->class == ARRAY && t2->class == ARRAY) { 11367ed027bSlinton b = TRUE; 11467ed027bSlinton } else { 11567ed027bSlinton b = FALSE; 116c9677cbaSlinton } 117c9677cbaSlinton /* 118c9677cbaSlinton * A kludge here for "nil". Should be handled better. 119c9677cbaSlinton * Opens a pandora's box for integer/pointer compatibility. 120c9677cbaSlinton */ 12167ed027bSlinton } else if ((t1->class == RANGE && t2->class == PTR) || 12267ed027bSlinton (t2->class == RANGE && t1->class == PTR)) { 12367ed027bSlinton b = TRUE; 12467ed027bSlinton } else { 12567ed027bSlinton b = FALSE; 126c9677cbaSlinton } 127c9677cbaSlinton } 12867ed027bSlinton return b; 129c9677cbaSlinton } 130c9677cbaSlinton 131c9677cbaSlinton /* 132c9677cbaSlinton * Predicate to test if a symbol should be printed. We don't print 133c9677cbaSlinton * files, for example, simply because there's no good way to do it. 134c9677cbaSlinton * The symbol must be within the given function. 135c9677cbaSlinton */ 136c9677cbaSlinton 137c9677cbaSlinton BOOLEAN should_print(s, f) 138c9677cbaSlinton SYM *s; 139c9677cbaSlinton SYM *f; 140c9677cbaSlinton { 141c9677cbaSlinton SYM *t; 142c9677cbaSlinton 143c9677cbaSlinton if (s->func != f || (s->class != VAR && s->class != FVAR)) { 144c9677cbaSlinton return(FALSE); 145c9677cbaSlinton } else if (s->chain != NIL) { 146c9677cbaSlinton return(FALSE); 147c9677cbaSlinton } else { 148c9677cbaSlinton t = rtype(s->type); 1495aa7b387Slinton if (t == NIL || t->class == FILET || t->class == SET) { 150c9677cbaSlinton return(FALSE); 151c9677cbaSlinton } else { 152c9677cbaSlinton return(TRUE); 153c9677cbaSlinton } 154c9677cbaSlinton } 155c9677cbaSlinton } 156c9677cbaSlinton 157c9677cbaSlinton /* 158c9677cbaSlinton * Test if the name of a symbol is uniquely defined or not. 159c9677cbaSlinton */ 160c9677cbaSlinton 161c9677cbaSlinton BOOLEAN isambiguous(s) 162c9677cbaSlinton SYM *s; 163c9677cbaSlinton { 164c9677cbaSlinton SYM *t; 165c9677cbaSlinton 166c9677cbaSlinton t = st_lookup(symtab, s->symbol); 167c9677cbaSlinton if (t == NIL) { 168c9677cbaSlinton panic("symbol name vanished"); 169c9677cbaSlinton } 170c9677cbaSlinton while (t != NIL && (s == t || !streq(t->symbol, s->symbol))) { 171c9677cbaSlinton t = t->next_sym; 172c9677cbaSlinton } 173c9677cbaSlinton return t != NIL; 174c9677cbaSlinton } 175