- (sizeof ((a) op (b)) < sizeof (t) \
- ? _GL_INT_OP_CALC1 ((t) (a), (t) (b), r, op, overflow, ut, t, tmin, tmax) \
- : _GL_INT_OP_CALC1 (a, b, r, op, overflow, ut, t, tmin, tmax))
-#define _GL_INT_OP_CALC1(a, b, r, op, overflow, ut, t, tmin, tmax) \
- ((overflow (a, b) \
- || (EXPR_SIGNED ((a) op (b)) && ((a) op (b)) < (tmin)) \
- || (tmax) < ((a) op (b))) \
- ? (*(r) = _GL_INT_OP_WRAPV_VIA_UNSIGNED (a, b, op, ut, t, tmin, tmax), 1) \
- : (*(r) = _GL_INT_OP_WRAPV_VIA_UNSIGNED (a, b, op, ut, t, tmin, tmax), 0))
-
-/* Return A <op> B, where the operation is given by OP. Use the
- unsigned type UT for calculation to avoid overflow problems.
- Convert the result to type T without overflow by subtracting TMIN
- from large values before converting, and adding it afterwards.
- Compilers can optimize all the operations except OP. */
-#define _GL_INT_OP_WRAPV_VIA_UNSIGNED(a, b, op, ut, t, tmin, tmax) \
- (((ut) (a) op (ut) (b)) <= (tmax) \
- ? (t) ((ut) (a) op (ut) (b)) \
- : ((t) (((ut) (a) op (ut) (b)) - (tmin)) + (tmin)))
+ (overflow (a, b, tmin, tmax) \
+ ? (*(r) = _GL_INT_OP_WRAPV_VIA_UNSIGNED (a, b, op, ut, t), 1) \
+ : (*(r) = _GL_INT_OP_WRAPV_VIA_UNSIGNED (a, b, op, ut, t), 0))
+
+/* Return the low-order bits of A <op> B, where the operation is given
+ by OP. Use the unsigned type UT for calculation to avoid undefined
+ behavior on signed integer overflow, and convert the result to type T.
+ UT is at least as wide as T and is no narrower than unsigned int,
+ T is two's complement, and there is no padding or trap representations.
+ Assume that converting UT to T yields the low-order bits, as is
+ done in all known two's-complement C compilers. E.g., see:
+ https://gcc.gnu.org/onlinedocs/gcc/Integers-implementation.html
+
+ According to the C standard, converting UT to T yields an
+ implementation-defined result or signal for values outside T's
+ range. However, code that works around this theoretical problem
+ runs afoul of a compiler bug in Oracle Studio 12.3 x86. See:
+ https://lists.gnu.org/r/bug-gnulib/2017-04/msg00049.html
+ As the compiler bug is real, don't try to work around the
+ theoretical problem. */
+
+#define _GL_INT_OP_WRAPV_VIA_UNSIGNED(a, b, op, ut, t) \
+ ((t) ((ut) (a) op (ut) (b)))
+
+/* Return true if the numeric values A + B, A - B, A * B fall outside
+ the range TMIN..TMAX. Arguments should be integer expressions
+ without side effects. TMIN should be signed and nonpositive.
+ TMAX should be positive, and should be signed unless TMIN is zero. */
+#define _GL_INT_ADD_RANGE_OVERFLOW(a, b, tmin, tmax) \
+ ((b) < 0 \
+ ? (((tmin) \
+ ? ((EXPR_SIGNED (_GL_INT_CONVERT (a, (tmin) - (b))) || (b) < (tmin)) \
+ && (a) < (tmin) - (b)) \
+ : (a) <= -1 - (b)) \
+ || ((EXPR_SIGNED (a) ? 0 <= (a) : (tmax) < (a)) && (tmax) < (a) + (b))) \
+ : (a) < 0 \
+ ? (((tmin) \
+ ? ((EXPR_SIGNED (_GL_INT_CONVERT (b, (tmin) - (a))) || (a) < (tmin)) \
+ && (b) < (tmin) - (a)) \
+ : (b) <= -1 - (a)) \
+ || ((EXPR_SIGNED (_GL_INT_CONVERT (a, b)) || (tmax) < (b)) \
+ && (tmax) < (a) + (b))) \
+ : (tmax) < (b) || (tmax) - (b) < (a))
+#define _GL_INT_SUBTRACT_RANGE_OVERFLOW(a, b, tmin, tmax) \
+ (((a) < 0) == ((b) < 0) \
+ ? ((a) < (b) \
+ ? !(tmin) || -1 - (tmin) < (b) - (a) - 1 \
+ : (tmax) < (a) - (b)) \
+ : (a) < 0 \
+ ? ((!EXPR_SIGNED (_GL_INT_CONVERT ((a) - (tmin), b)) && (a) - (tmin) < 0) \
+ || (a) - (tmin) < (b)) \
+ : ((! (EXPR_SIGNED (_GL_INT_CONVERT (tmax, b)) \
+ && EXPR_SIGNED (_GL_INT_CONVERT ((tmax) + (b), a))) \
+ && (tmax) <= -1 - (b)) \
+ || (tmax) + (b) < (a)))
+#define _GL_INT_MULTIPLY_RANGE_OVERFLOW(a, b, tmin, tmax) \
+ ((b) < 0 \
+ ? ((a) < 0 \
+ ? (EXPR_SIGNED (_GL_INT_CONVERT (tmax, b)) \
+ ? (a) < (tmax) / (b) \
+ : ((INT_NEGATE_OVERFLOW (b) \
+ ? _GL_INT_CONVERT (b, tmax) >> (TYPE_WIDTH (b) - 1) \
+ : (tmax) / -(b)) \
+ <= -1 - (a))) \
+ : INT_NEGATE_OVERFLOW (_GL_INT_CONVERT (b, tmin)) && (b) == -1 \
+ ? (EXPR_SIGNED (a) \
+ ? 0 < (a) + (tmin) \
+ : 0 < (a) && -1 - (tmin) < (a) - 1) \
+ : (tmin) / (b) < (a)) \
+ : (b) == 0 \
+ ? 0 \
+ : ((a) < 0 \
+ ? (INT_NEGATE_OVERFLOW (_GL_INT_CONVERT (a, tmin)) && (a) == -1 \
+ ? (EXPR_SIGNED (b) ? 0 < (b) + (tmin) : -1 - (tmin) < (b) - 1) \
+ : (tmin) / (a) < (b)) \
+ : (tmax) / (b) < (a)))