Add `-integer-division-by-zero:all-bits`

src/build_settings.cpp

@@ -353,14 +353,18 @@ enum OptInFeatureFlags : u64 {
 	OptInFeatureFlag_NONE            = 0,
 	OptInFeatureFlag_DynamicLiterals = 1u<<0,
 
-	OptInFeatureFlag_IntegerDivisionByZero_Trap = 1u<<1,
-	OptInFeatureFlag_IntegerDivisionByZero_Zero = 1u<<2,
-	OptInFeatureFlag_IntegerDivisionByZero_Self = 1u<<3,
+	OptInFeatureFlag_GlobalContext = 1u<<1,
 
-	OptInFeatureFlag_GlobalContext = 1u<<4,
+	OptInFeatureFlag_IntegerDivisionByZero_Trap    = 1u<<2,
+	OptInFeatureFlag_IntegerDivisionByZero_Zero    = 1u<<3,
+	OptInFeatureFlag_IntegerDivisionByZero_Self    = 1u<<4,
+	OptInFeatureFlag_IntegerDivisionByZero_AllBits = 1u<<5,
 
 
-	OptInFeatureFlag_IntegerDivisionByZero_ALL = OptInFeatureFlag_IntegerDivisionByZero_Trap|OptInFeatureFlag_IntegerDivisionByZero_Zero|OptInFeatureFlag_IntegerDivisionByZero_Self,
+	OptInFeatureFlag_IntegerDivisionByZero_ALL = OptInFeatureFlag_IntegerDivisionByZero_Trap|
+	                                             OptInFeatureFlag_IntegerDivisionByZero_Zero|
+	                                             OptInFeatureFlag_IntegerDivisionByZero_Self|
+	                                             OptInFeatureFlag_IntegerDivisionByZero_AllBits,
 
 };
 
@@ -377,6 +381,10 @@ u64 get_feature_flag_from_name(String const &name) {
 	if (name == "integer-division-by-zero:self") {
 		return OptInFeatureFlag_IntegerDivisionByZero_Self;
 	}
+	if (name == "integer-division-by-zero:all-bits") {
+		return OptInFeatureFlag_IntegerDivisionByZero_AllBits;
+	}
+
 
 	if (name == "global-context") {
 		return OptInFeatureFlag_GlobalContext;
@@ -431,6 +439,7 @@ enum IntegerDivisionByZeroKind : u8 {
 	IntegerDivisionByZero_Trap,
 	IntegerDivisionByZero_Zero,
 	IntegerDivisionByZero_Self,
+	IntegerDivisionByZero_AllBits,
 };
 
 // This stores the information for the specify architecture of this build

src/check_expr.cpp

@@ -4377,12 +4377,23 @@ gb_internal void check_binary_expr(CheckerContext *c, Operand *x, Ast *node, Typ
 		    b.kind == ExactValue_Integer && big_int_is_zero(&b.value_integer) &&
 		    (op.kind == Token_QuoEq || op.kind == Token_Mod || op.kind == Token_ModMod)) {
 		    	if (op.kind == Token_QuoEq) {
-		    		if (zero_behaviour == IntegerDivisionByZero_Zero) {
+		    		switch (zero_behaviour) {
+		    		case IntegerDivisionByZero_Zero:
 			    		// x/0 == 0
 					x->value = b;
-				} else {
+					break;
+				case IntegerDivisionByZero_Self:
 			    		// x/0 == x
 					x->value = a;
+					break;
+				case IntegerDivisionByZero_AllBits:
+			    		// x/0 == 0b111...111
+			    		if (is_type_untyped(x->type)) {
+			    			x->value = exact_value_i64(-1);
+			    		} else {
+						x->value = exact_unary_operator_value(Token_Xor, b, cast(i32)(8*type_size_of(x->type)), is_type_unsigned(x->type));
+					}
+					break;
 				}
 			} else {
 		    		/*
@@ -4391,16 +4402,21 @@ gb_internal void check_binary_expr(CheckerContext *c, Operand *x, Ast *node, Typ
 		    			truncated: r = a - b*trunc(a/b)
 		    			floored:   r = a - b*floor(a/b)
 
-		    			IFF a/0 == 0, then (a%0 == a) or (a%%0 == a)
-		    			IFF a/0 == a, then (a%0 == 0) or (a%%0 == 0)
+		    			IFF a/0 == 0,        then (a%0 == a) or (a%%0 == a)
+		    			IFF a/0 == a,        then (a%0 == 0) or (a%%0 == 0)
+		    			IFF a/0 == 0b111..., then (a%0 == a) or (a%%0 == a)
 		    		*/
 
-		    		if (zero_behaviour == IntegerDivisionByZero_Zero) {
+				switch (zero_behaviour) {
+				case IntegerDivisionByZero_Zero:
+				case IntegerDivisionByZero_AllBits:
 			    		// x%0 == x
 					x->value = a;
-				} else {
+					break;
+				case IntegerDivisionByZero_Self:
 			    		// x%0 == 0
 					x->value = b;
+					break;
 				}
 			}
 		} else {
@@ -9670,6 +9686,9 @@ gb_internal IntegerDivisionByZeroKind check_for_integer_division_by_zero(Checker
 	if ((flags & OptInFeatureFlag_IntegerDivisionByZero_Self) != 0) {
 		return IntegerDivisionByZero_Self;
 	}
+	if ((flags & OptInFeatureFlag_IntegerDivisionByZero_AllBits) != 0) {
+		return IntegerDivisionByZero_AllBits;
+	}
 	return build_context.integer_division_by_zero_behaviour;
 }
 

src/llvm_backend_expr.cpp

@@ -305,6 +305,9 @@ gb_internal IntegerDivisionByZeroKind lb_check_for_integer_division_by_zero_beha
 		if (flags & OptInFeatureFlag_IntegerDivisionByZero_Self) {
 			return IntegerDivisionByZero_Self;
 		}
+		if (flags & OptInFeatureFlag_IntegerDivisionByZero_AllBits) {
+			return IntegerDivisionByZero_AllBits;
+		}
 	}
 	return build_context.integer_division_by_zero_behaviour;
 }
@@ -1140,6 +1143,7 @@ gb_internal LLVMValueRef lb_integer_division(lbProcedure *p, LLVMValueRef lhs, L
 	GB_ASSERT(LLVMTypeOf(lhs) == type);
 
 	LLVMValueRef zero = LLVMConstNull(type);
+	LLVMValueRef all_bits = LLVMConstNot(zero);
 	auto behaviour = lb_check_for_integer_division_by_zero_behaviour(p);
 
 	auto *call = is_signed ? LLVMBuildSDiv : LLVMBuildUDiv;
@@ -1151,6 +1155,9 @@ gb_internal LLVMValueRef lb_integer_division(lbProcedure *p, LLVMValueRef lhs, L
 				return lhs;
 			case IntegerDivisionByZero_Zero:
 				return zero;
+			case IntegerDivisionByZero_AllBits:
+				// return all_bits;
+				break;
 			}
 		} else {
 			if (!is_signed && lb_sizeof(type) <= 8) {
@@ -1198,6 +1205,9 @@ gb_internal LLVMValueRef lb_integer_division(lbProcedure *p, LLVMValueRef lhs, L
 	case IntegerDivisionByZero_Self:
 		incoming_values[1] = lhs;
 		break;
+	case IntegerDivisionByZero_AllBits:
+		incoming_values[1] = all_bits;
+		break;
 	}
 
 	lb_emit_jump(p, done_block);
@@ -1211,6 +1221,7 @@ gb_internal LLVMValueRef lb_integer_division(lbProcedure *p, LLVMValueRef lhs, L
 		res = incoming_values[0];
 		break;
 	case IntegerDivisionByZero_Zero:
+	case IntegerDivisionByZero_AllBits:
 		res = LLVMBuildPhi(p->builder, type, "");
 
 		GB_ASSERT(p->curr_block->preds.count >= 2);
@@ -1229,6 +1240,7 @@ gb_internal LLVMValueRef lb_integer_division_intrinsics(lbProcedure *p, LLVMValu
 	GB_ASSERT(LLVMTypeOf(lhs) == type);
 
 	LLVMValueRef zero = LLVMConstNull(type);
+	LLVMValueRef all_bits = LLVMConstNot(zero);
 	auto behaviour = lb_check_for_integer_division_by_zero_behaviour(p);
 
 	auto const do_op = [&]() -> LLVMValueRef {
@@ -1285,6 +1297,9 @@ gb_internal LLVMValueRef lb_integer_division_intrinsics(lbProcedure *p, LLVMValu
 	case IntegerDivisionByZero_Self:
 		incoming_values[1] = lhs;
 		break;
+	case IntegerDivisionByZero_AllBits:
+		incoming_values[1] = all_bits;
+		break;
 	}
 
 	lb_emit_jump(p, done_block);
@@ -1298,6 +1313,7 @@ gb_internal LLVMValueRef lb_integer_division_intrinsics(lbProcedure *p, LLVMValu
 		res = incoming_values[0];
 		break;
 	case IntegerDivisionByZero_Zero:
+	case IntegerDivisionByZero_AllBits:
 		res = LLVMBuildPhi(p->builder, type, "");
 
 		GB_ASSERT(p->curr_block->preds.count >= 2);
@@ -1344,6 +1360,7 @@ gb_internal LLVMValueRef lb_integer_modulo(lbProcedure *p, LLVMValueRef lhs, LLV
 			case IntegerDivisionByZero_Self:
 				return zero;
 			case IntegerDivisionByZero_Zero:
+			case IntegerDivisionByZero_AllBits:
 				return lhs;
 			}
 		} else {
@@ -1386,6 +1403,7 @@ gb_internal LLVMValueRef lb_integer_modulo(lbProcedure *p, LLVMValueRef lhs, LLV
 		LLVMBuildUnreachable(p->builder);
 		break;
 	case IntegerDivisionByZero_Zero:
+	case IntegerDivisionByZero_AllBits:
 		incoming_values[1] = lhs;
 		break;
 	case IntegerDivisionByZero_Self:
@@ -1404,6 +1422,7 @@ gb_internal LLVMValueRef lb_integer_modulo(lbProcedure *p, LLVMValueRef lhs, LLV
 		res = incoming_values[0];
 		break;
 	case IntegerDivisionByZero_Zero:
+	case IntegerDivisionByZero_AllBits:
 		res = LLVMBuildPhi(p->builder, type, "");
 
 		GB_ASSERT(p->curr_block->preds.count >= 2);

src/main.cpp

@@ -2589,6 +2589,7 @@ gb_internal int print_show_help(String const arg0, String command, String option
 			print_usage_line(3, "-integer-division-by-zero:trap        Trap on division/modulo/remainder by zero");
 			print_usage_line(3, "-integer-division-by-zero:zero        x/0 == 0 and x%%0 == x and x%%%%0 == x");
 			print_usage_line(3, "-integer-division-by-zero:self        x/0 == x and x%%0 == 0 and x%%%%0 == 0");
+			print_usage_line(3, "-integer-division-by-zero:all-bits    x/0 == ~T(0) and x%%0 == x and x%%%%0 == x");
 		}
 	}