#include "perms.h" // 1 %begin #line 1 "prec.imp" int main(int argc, char **argv) { __label__ _imp_endofblock; _imp_initialise(argc, argv); // 2 // 3 ! // 4 ! Precedence of operators // 5 ! // 6 ! Highest: 1. \ (complement, unary not) // 7 ! 2. \, \\, <<, >> // 8 ! 3. *, /, //, & // 9 ! Lowest: 4. +, - (unary and binary), !, !! // 10 ! // 11 ! In general, sub-expressions with operators of equal precedence are evaluated from left to right. // 12 ! // 13 ! The one exception to the left-hand precedence rule is that consecutive // 14 ! exponentiations are evaluated from right to left; thus A**B**C is // 15 ! evaluated as A**(B**C), not as (A**B)**C. (Imp80 documentation) // 16 // 17 ! Arithmetic operators: // 18 // 19 ! |...| modulus also: !...! (deprecated some time ago) // 20 // 21 ! ! inclusive or // 22 ! !! exclusive or // 23 ! & and // 24 // 25 ! \ real exponentiation also: ^ (Imp77) or ** (ERCC compilers) // 26 ! \\ integer exponentiation also: ^^ (Imp77) or **** // 27 // 28 ! * multiply // 29 ! / real division // 30 ! // integer division // 31 // 32 ! << left shift // 33 ! >> right shift // 34 // 35 ! + plus // 36 ! - minus // 37 // 38 ! + unary + // 39 ! - unary - // 40 ! \ unary not also ~ (can be *displayed* as: ¬ (¬)) // 41 // 42 ! . string concatenation // 43 // 44 ! Comparison operators: // 45 ! = eq // 46 ! # not equals also \= and <> (Imp80 documentation) // 47 ! == address equals // 48 ! ## address not equals also \== // 49 ! -> string resolution (a difficult to classify hybrid of a comparison and an assignment operator) // 50 ! <= less than or equals // 51 ! < less than // 52 ! >= greater than or equals // 53 ! > // 54 // 55 ! Assignment operators: // 56 ! = assignment // 57 ! == pointer assignment // 58 ! <- jam transfer // 59 ! -> string resolution // 60 // 61 ! Data structure operators: // 62 ! _ record field // 63 ! () array indexing // 64 ! [] pointer increment (a Hamish extension in 68000 Imp only) // 65 // 66 ! Other: // 67 ! @ may be considered an operator in %real literals, usually handled by a BIP. // 68 // 69 // 70 %const %integer a = 19, b = 17, c = 5, d = 3 _imp_current_line = 70; _imp_current_file = "prec.imp"; // 71 %integer x = a * b // c * d _imp_current_line = 71; _imp_current_file = "prec.imp"; #line 71 "prec.imp" int X; #line 71 "prec.imp" X = (((((((((int)(19)) * (17)))) / ((int)(5))))) * (3)); // 72 print string("Imp77 precedence and associativity test."); newlines(2) _imp_current_line = 72; _imp_current_file = "prec.imp"; #line 72 "prec.imp" _imp_PRINTSTRING(_imp_str_literal("Imp77 precedence and associativity test.")); _imp_current_line = 72; _imp_current_file = "prec.imp"; #line 72 "prec.imp" _imp_NEWLINES(2); // 73 %if x = 21 %start _imp_current_line = 73; _imp_current_file = "prec.imp"; #line 73 "prec.imp" if (((X) != (21))) goto L_0002; // 74 print string("In a * b // c * d, '*' has higher priority than '/'."); newline _imp_current_line = 74; _imp_current_file = "prec.imp"; #line 74 "prec.imp" _imp_PRINTSTRING(_imp_str_literal("In a * b // c * d, '*' has higher priority than '/'.")); _imp_current_line = 74; _imp_current_file = "prec.imp"; #line 74 "prec.imp" _imp_NEWLINE(); // 75 print string("A second test with '/' will be needed to determine associativity:"); newline _imp_current_line = 75; _imp_current_file = "prec.imp"; #line 75 "prec.imp" _imp_PRINTSTRING(_imp_str_literal("A second test with '/' will be needed to determine associativity:")); _imp_current_line = 75; _imp_current_file = "prec.imp"; #line 75 "prec.imp" _imp_NEWLINE(); // 76 x = a // c // d _imp_current_line = 76; _imp_current_file = "prec.imp"; #line 76 "prec.imp" X = (((((((int)(19)) / ((int)(5)))))) / ((int)(3))); // 77 %if x = 1 %start _imp_current_line = 77; _imp_current_file = "prec.imp"; #line 77 "prec.imp" if (((X) != (1))) goto L_0003; // 78 print string("a // c // d is right associative, i.e. a // (b // c)"); newline _imp_current_line = 78; _imp_current_file = "prec.imp"; #line 78 "prec.imp" _imp_PRINTSTRING(_imp_str_literal("a // c // d is right associative, i.e. a // (b // c)")); _imp_current_line = 78; _imp_current_file = "prec.imp"; #line 78 "prec.imp" _imp_NEWLINE(); // 79 %else %if x = 19 _imp_current_line = 79; _imp_current_file = "prec.imp"; #line 79 "prec.imp" goto L_0004; #line 79 "prec.imp" L_0003:; #line 79 "prec.imp" if (((X) != (19))) goto L_0005; // 80 print string("a // c // d is left associative, i.e. (a // b) // c"); newline _imp_current_line = 80; _imp_current_file = "prec.imp"; #line 80 "prec.imp" _imp_PRINTSTRING(_imp_str_literal("a // c // d is left associative, i.e. (a // b) // c")); _imp_current_line = 80; _imp_current_file = "prec.imp"; #line 80 "prec.imp" _imp_NEWLINE(); // 81 %else _imp_current_line = 81; _imp_current_file = "prec.imp"; #line 81 "prec.imp" goto L_0004; #line 81 "prec.imp" L_0005:; // 82 print string("a // c // d is something weird! I give up."); newline _imp_current_line = 82; _imp_current_file = "prec.imp"; #line 82 "prec.imp" _imp_PRINTSTRING(_imp_str_literal("a // c // d is something weird! I give up.")); _imp_current_line = 82; _imp_current_file = "prec.imp"; #line 82 "prec.imp" _imp_NEWLINE(); // 83 %finish _imp_current_line = 83; _imp_current_file = "prec.imp"; #line 83 "prec.imp" L_0004:; // 84 %else %if x = 19 _imp_current_line = 84; _imp_current_file = "prec.imp"; #line 84 "prec.imp" goto L_0006; #line 84 "prec.imp" L_0002:; #line 84 "prec.imp" if (((X) != (19))) goto L_0007; // 85 print string("a * b // c * d is right associative and with equal precedence, i.e. a * (b // (c * d))"); newline _imp_current_line = 85; _imp_current_file = "prec.imp"; #line 85 "prec.imp" _imp_PRINTSTRING(_imp_str_literal("a * b // c * d is right associative and with equal precedence, i.e. a * (b // (c * d))")); _imp_current_line = 85; _imp_current_file = "prec.imp"; #line 85 "prec.imp" _imp_NEWLINE(); // 86 newline _imp_current_line = 86; _imp_current_file = "prec.imp"; #line 86 "prec.imp" _imp_NEWLINE(); // 87 print string("This grammar would support the above:"); newline _imp_current_line = 87; _imp_current_file = "prec.imp"; #line 87 "prec.imp" _imp_PRINTSTRING(_imp_str_literal("This grammar would support the above:")); _imp_current_line = 87; _imp_current_file = "prec.imp"; #line 87 "prec.imp" _imp_NEWLINE(); // 88 newline _imp_current_line = 88; _imp_current_file = "prec.imp"; #line 88 "prec.imp" _imp_NEWLINE(); // 89 print string("P = ;"); newline _imp_current_line = 89; _imp_current_file = "prec.imp"; #line 89 "prec.imp" _imp_PRINTSTRING(_imp_str_literal("P = ;")); _imp_current_line = 89; _imp_current_file = "prec.imp"; #line 89 "prec.imp" _imp_NEWLINE(); // 90 print string("P = | ;"); newline _imp_current_line = 90; _imp_current_file = "prec.imp"; #line 90 "prec.imp" _imp_PRINTSTRING(_imp_str_literal("P = | ;")); _imp_current_line = 90; _imp_current_file = "prec.imp"; #line 90 "prec.imp" _imp_NEWLINE(); // 91 print string("P = ;"); newline _imp_current_line = 91; _imp_current_file = "prec.imp"; #line 91 "prec.imp" _imp_PRINTSTRING(_imp_str_literal("P = ;")); _imp_current_line = 91; _imp_current_file = "prec.imp"; #line 91 "prec.imp" _imp_NEWLINE(); // 92 %else %if x = 192 _imp_current_line = 92; _imp_current_file = "prec.imp"; #line 92 "prec.imp" goto L_0006; #line 92 "prec.imp" L_0007:; #line 92 "prec.imp" if (((X) != (192))) goto L_0008; // 93 print string("a * b // c * d is left associative and with equal precedence, i.e. ((a * b) // c) * d"); newline _imp_current_line = 93; _imp_current_file = "prec.imp"; #line 93 "prec.imp" _imp_PRINTSTRING(_imp_str_literal("a * b // c * d is left associative and with equal precedence, i.e. ((a * b) // c) * d")); _imp_current_line = 93; _imp_current_file = "prec.imp"; #line 93 "prec.imp" _imp_NEWLINE(); // 94 newline _imp_current_line = 94; _imp_current_file = "prec.imp"; #line 94 "prec.imp" _imp_NEWLINE(); // 95 print string("This grammar would support the above:"); newline _imp_current_line = 95; _imp_current_file = "prec.imp"; #line 95 "prec.imp" _imp_PRINTSTRING(_imp_str_literal("This grammar would support the above:")); _imp_current_line = 95; _imp_current_file = "prec.imp"; #line 95 "prec.imp" _imp_NEWLINE(); // 96 newline _imp_current_line = 96; _imp_current_file = "prec.imp"; #line 96 "prec.imp" _imp_NEWLINE(); // 97 print string("P = ;"); newline _imp_current_line = 97; _imp_current_file = "prec.imp"; #line 97 "prec.imp" _imp_PRINTSTRING(_imp_str_literal("P = ;")); _imp_current_line = 97; _imp_current_file = "prec.imp"; #line 97 "prec.imp" _imp_NEWLINE(); // 98 print string("P = | ;"); newline _imp_current_line = 98; _imp_current_file = "prec.imp"; #line 98 "prec.imp" _imp_PRINTSTRING(_imp_str_literal("P = | ;")); _imp_current_line = 98; _imp_current_file = "prec.imp"; #line 98 "prec.imp" _imp_NEWLINE(); // 99 print string("P = ;"); newline _imp_current_line = 99; _imp_current_file = "prec.imp"; #line 99 "prec.imp" _imp_PRINTSTRING(_imp_str_literal("P = ;")); _imp_current_line = 99; _imp_current_file = "prec.imp"; #line 99 "prec.imp" _imp_NEWLINE(); // 100 %else _imp_current_line = 100; _imp_current_file = "prec.imp"; #line 100 "prec.imp" goto L_0006; #line 100 "prec.imp" L_0008:; // 101 print string("a * b // c * d uses some weird non-standard combination of precedence and associativity!"); newline _imp_current_line = 101; _imp_current_file = "prec.imp"; #line 101 "prec.imp" _imp_PRINTSTRING(_imp_str_literal("a * b // c * d uses some weird non-standard combination of precedence and associativity!")); _imp_current_line = 101; _imp_current_file = "prec.imp"; #line 101 "prec.imp" _imp_NEWLINE(); // 102 %finish _imp_current_line = 102; _imp_current_file = "prec.imp"; #line 102 "prec.imp" L_0006:; // 103 newline _imp_current_line = 103; _imp_current_file = "prec.imp"; #line 103 "prec.imp" _imp_NEWLINE(); // 104 // 105 // 106 %const %integer p = 4, q = 3, r = 2 _imp_current_line = 106; _imp_current_file = "prec.imp"; // 107 %integer y _imp_current_line = 107; _imp_current_file = "prec.imp"; #line 107 "prec.imp" int Y; // 108 // 109 y = p ^^ q ^^ r _imp_current_line = 109; _imp_current_file = "prec.imp"; #line 109 "prec.imp" Y = _imp_IEXP(_imp_IEXP(4, 3), 2); // 110 // 111 %if y = 262144 %start _imp_current_line = 111; _imp_current_file = "prec.imp"; #line 111 "prec.imp" if (((Y) != (262144))) goto L_0009; // 112 print string("p ^^ q ^^ r is right associative, i.e. p ^^ (q ^^ r)"); newline _imp_current_line = 112; _imp_current_file = "prec.imp"; #line 112 "prec.imp" _imp_PRINTSTRING(_imp_str_literal("p ^^ q ^^ r is right associative, i.e. p ^^ (q ^^ r)")); _imp_current_line = 112; _imp_current_file = "prec.imp"; #line 112 "prec.imp" _imp_NEWLINE(); // 113 newline _imp_current_line = 113; _imp_current_file = "prec.imp"; #line 113 "prec.imp" _imp_NEWLINE(); // 114 print string("This grammar would support the above:"); newline _imp_current_line = 114; _imp_current_file = "prec.imp"; #line 114 "prec.imp" _imp_PRINTSTRING(_imp_str_literal("This grammar would support the above:")); _imp_current_line = 114; _imp_current_file = "prec.imp"; #line 114 "prec.imp" _imp_NEWLINE(); // 115 newline _imp_current_line = 115; _imp_current_file = "prec.imp"; #line 115 "prec.imp" _imp_NEWLINE(); // 116 print string("P = ;"); newline _imp_current_line = 116; _imp_current_file = "prec.imp"; #line 116 "prec.imp" _imp_PRINTSTRING(_imp_str_literal("P = ;")); _imp_current_line = 116; _imp_current_file = "prec.imp"; #line 116 "prec.imp" _imp_NEWLINE(); // 117 print string("P = | ;"); newline _imp_current_line = 117; _imp_current_file = "prec.imp"; #line 117 "prec.imp" _imp_PRINTSTRING(_imp_str_literal("P = | ;")); _imp_current_line = 117; _imp_current_file = "prec.imp"; #line 117 "prec.imp" _imp_NEWLINE(); // 118 print string("P = ""^^"" ;"); newline _imp_current_line = 118; _imp_current_file = "prec.imp"; #line 118 "prec.imp" _imp_PRINTSTRING(_imp_str_literal("P = \"^^\" ;")); _imp_current_line = 118; _imp_current_file = "prec.imp"; #line 118 "prec.imp" _imp_NEWLINE(); // 119 %else %if y = 4096 _imp_current_line = 119; _imp_current_file = "prec.imp"; #line 119 "prec.imp" goto L_000a; #line 119 "prec.imp" L_0009:; #line 119 "prec.imp" if (((Y) != (4096))) goto L_000b; // 120 print string("p ^^ q ^^ r is left associative, i.e. (p ^^ q) ^^ r"); newline _imp_current_line = 120; _imp_current_file = "prec.imp"; #line 120 "prec.imp" _imp_PRINTSTRING(_imp_str_literal("p ^^ q ^^ r is left associative, i.e. (p ^^ q) ^^ r")); _imp_current_line = 120; _imp_current_file = "prec.imp"; #line 120 "prec.imp" _imp_NEWLINE(); // 121 newline _imp_current_line = 121; _imp_current_file = "prec.imp"; #line 121 "prec.imp" _imp_NEWLINE(); // 122 print string("This grammar would support the above:"); newline _imp_current_line = 122; _imp_current_file = "prec.imp"; #line 122 "prec.imp" _imp_PRINTSTRING(_imp_str_literal("This grammar would support the above:")); _imp_current_line = 122; _imp_current_file = "prec.imp"; #line 122 "prec.imp" _imp_NEWLINE(); // 123 newline _imp_current_line = 123; _imp_current_file = "prec.imp"; #line 123 "prec.imp" _imp_NEWLINE(); // 124 print string("P = ;"); newline _imp_current_line = 124; _imp_current_file = "prec.imp"; #line 124 "prec.imp" _imp_PRINTSTRING(_imp_str_literal("P = ;")); _imp_current_line = 124; _imp_current_file = "prec.imp"; #line 124 "prec.imp" _imp_NEWLINE(); // 125 print string("P = | ;"); newline _imp_current_line = 125; _imp_current_file = "prec.imp"; #line 125 "prec.imp" _imp_PRINTSTRING(_imp_str_literal("P = | ;")); _imp_current_line = 125; _imp_current_file = "prec.imp"; #line 125 "prec.imp" _imp_NEWLINE(); // 126 print string("P = ""^^"" ;"); newline _imp_current_line = 126; _imp_current_file = "prec.imp"; #line 126 "prec.imp" _imp_PRINTSTRING(_imp_str_literal("P = \"^^\" ;")); _imp_current_line = 126; _imp_current_file = "prec.imp"; #line 126 "prec.imp" _imp_NEWLINE(); // 127 %else _imp_current_line = 127; _imp_current_file = "prec.imp"; #line 127 "prec.imp" goto L_000a; #line 127 "prec.imp" L_000b:; // 128 print string("p ^^ q ^^ r is something weird! ("); write(y, 0); print string(") - I give up."); newline _imp_current_line = 128; _imp_current_file = "prec.imp"; #line 128 "prec.imp" _imp_PRINTSTRING(_imp_str_literal("p ^^ q ^^ r is something weird! (")); _imp_current_line = 128; _imp_current_file = "prec.imp"; #line 128 "prec.imp" _imp_WRITE(Y, 0); _imp_current_line = 128; _imp_current_file = "prec.imp"; #line 128 "prec.imp" _imp_PRINTSTRING(_imp_str_literal(") - I give up.")); _imp_current_line = 128; _imp_current_file = "prec.imp"; #line 128 "prec.imp" _imp_NEWLINE(); // 129 %finish _imp_current_line = 129; _imp_current_file = "prec.imp"; #line 129 "prec.imp" L_000a:; // 130 newline _imp_current_line = 130; _imp_current_file = "prec.imp"; #line 130 "prec.imp" _imp_NEWLINE(); // 131 // 132 ! The remaining issue to be checked is how left/right associativity interact when the precedence is the same, // 133 ! which is only the case for exponentiation and shifts together, eg // 134 ! // 135 ! a << b << c ^^ d ^^ e or a ^^ b ^^ c >> d >> e // 136 ! // 137 // 138 %endofprogram _imp_current_line = 138; _imp_current_file = "prec.imp"; #line 138 "prec.imp" return 0; _imp_endofblock: ; } // End of block _imp_main at level 1 #line 138 "prec.imp" // End of file // COMPILE WITH: gcc12 -DVALGRIND_AVAILABLE -UPARM_OPT -DPARM_UNASS -DPARM_CHECK -O -g -ftrivial-auto-var-init=pattern -fmerge-constants -fno-strict-aliasing -Wall -Wno-unused-but-set-variable -Wno-unused-variable -Wno-unused-label -Wno-unused-function -Wno-maybe-uninitialized -Wno-uninitialized -frecord-gcc-switches -fsanitize=undefined -fsanitize=float-divide-by-zero -fsanitize-undefined-trap-on-error -fsanitize=float-cast-overflow -fno-sanitize-recover=all -fstack-protector -Wno-frame-address -fno-omit-frame-pointer -Wno-return-type -Wno-comment -ftrapv -ggdb3 -gdwarf-4 -I. -I.. -c -o prec.o prec.c -lm