Adding upstream version 14.5.upstream/14.5upstream

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 437 insertions, 0 deletions

diff --git a/src/include/common/int.h b/src/include/common/int.h
new file mode 100644
index 0000000..079954d
--- /dev/null
+++ b/src/include/common/int.h
@@ -0,0 +1,437 @@
+/*-------------------------------------------------------------------------
+ *
+ * int.h
+ *	  Routines to perform integer math, while checking for overflows.
+ *
+ * The routines in this file are intended to be well defined C, without
+ * relying on compiler flags like -fwrapv.
+ *
+ * To reduce the overhead of these routines try to use compiler intrinsics
+ * where available. That's not that important for the 16, 32 bit cases, but
+ * the 64 bit cases can be considerably faster with intrinsics. In case no
+ * intrinsics are available 128 bit math is used where available.
+ *
+ * Copyright (c) 2017-2021, PostgreSQL Global Development Group
+ *
+ * src/include/common/int.h
+ *
+ *-------------------------------------------------------------------------
+ */
+#ifndef COMMON_INT_H
+#define COMMON_INT_H
+
+
+/*---------
+ * The following guidelines apply to all the routines:
+ * - If a + b overflows, return true, otherwise store the result of a + b
+ * into *result. The content of *result is implementation defined in case of
+ * overflow.
+ * - If a - b overflows, return true, otherwise store the result of a - b
+ * into *result. The content of *result is implementation defined in case of
+ * overflow.
+ * - If a * b overflows, return true, otherwise store the result of a * b
+ * into *result. The content of *result is implementation defined in case of
+ * overflow.
+ *---------
+ */
+
+/*------------------------------------------------------------------------
+ * Overflow routines for signed integers
+ *------------------------------------------------------------------------
+ */
+
+/*
+ * INT16
+ */
+static inline bool
+pg_add_s16_overflow(int16 a, int16 b, int16 *result)
+{
+#if defined(HAVE__BUILTIN_OP_OVERFLOW)
+	return __builtin_add_overflow(a, b, result);
+#else
+	int32		res = (int32) a + (int32) b;
+
+	if (res > PG_INT16_MAX || res < PG_INT16_MIN)
+	{
+		*result = 0x5EED;		/* to avoid spurious warnings */
+		return true;
+	}
+	*result = (int16) res;
+	return false;
+#endif
+}
+
+static inline bool
+pg_sub_s16_overflow(int16 a, int16 b, int16 *result)
+{
+#if defined(HAVE__BUILTIN_OP_OVERFLOW)
+	return __builtin_sub_overflow(a, b, result);
+#else
+	int32		res = (int32) a - (int32) b;
+
+	if (res > PG_INT16_MAX || res < PG_INT16_MIN)
+	{
+		*result = 0x5EED;		/* to avoid spurious warnings */
+		return true;
+	}
+	*result = (int16) res;
+	return false;
+#endif
+}
+
+static inline bool
+pg_mul_s16_overflow(int16 a, int16 b, int16 *result)
+{
+#if defined(HAVE__BUILTIN_OP_OVERFLOW)
+	return __builtin_mul_overflow(a, b, result);
+#else
+	int32		res = (int32) a * (int32) b;
+
+	if (res > PG_INT16_MAX || res < PG_INT16_MIN)
+	{
+		*result = 0x5EED;		/* to avoid spurious warnings */
+		return true;
+	}
+	*result = (int16) res;
+	return false;
+#endif
+}
+
+/*
+ * INT32
+ */
+static inline bool
+pg_add_s32_overflow(int32 a, int32 b, int32 *result)
+{
+#if defined(HAVE__BUILTIN_OP_OVERFLOW)
+	return __builtin_add_overflow(a, b, result);
+#else
+	int64		res = (int64) a + (int64) b;
+
+	if (res > PG_INT32_MAX || res < PG_INT32_MIN)
+	{
+		*result = 0x5EED;		/* to avoid spurious warnings */
+		return true;
+	}
+	*result = (int32) res;
+	return false;
+#endif
+}
+
+static inline bool
+pg_sub_s32_overflow(int32 a, int32 b, int32 *result)
+{
+#if defined(HAVE__BUILTIN_OP_OVERFLOW)
+	return __builtin_sub_overflow(a, b, result);
+#else
+	int64		res = (int64) a - (int64) b;
+
+	if (res > PG_INT32_MAX || res < PG_INT32_MIN)
+	{
+		*result = 0x5EED;		/* to avoid spurious warnings */
+		return true;
+	}
+	*result = (int32) res;
+	return false;
+#endif
+}
+
+static inline bool
+pg_mul_s32_overflow(int32 a, int32 b, int32 *result)
+{
+#if defined(HAVE__BUILTIN_OP_OVERFLOW)
+	return __builtin_mul_overflow(a, b, result);
+#else
+	int64		res = (int64) a * (int64) b;
+
+	if (res > PG_INT32_MAX || res < PG_INT32_MIN)
+	{
+		*result = 0x5EED;		/* to avoid spurious warnings */
+		return true;
+	}
+	*result = (int32) res;
+	return false;
+#endif
+}
+
+/*
+ * INT64
+ */
+static inline bool
+pg_add_s64_overflow(int64 a, int64 b, int64 *result)
+{
+#if defined(HAVE__BUILTIN_OP_OVERFLOW)
+	return __builtin_add_overflow(a, b, result);
+#elif defined(HAVE_INT128)
+	int128		res = (int128) a + (int128) b;
+
+	if (res > PG_INT64_MAX || res < PG_INT64_MIN)
+	{
+		*result = 0x5EED;		/* to avoid spurious warnings */
+		return true;
+	}
+	*result = (int64) res;
+	return false;
+#else
+	if ((a > 0 && b > 0 && a > PG_INT64_MAX - b) ||
+		(a < 0 && b < 0 && a < PG_INT64_MIN - b))
+	{
+		*result = 0x5EED;		/* to avoid spurious warnings */
+		return true;
+	}
+	*result = a + b;
+	return false;
+#endif
+}
+
+static inline bool
+pg_sub_s64_overflow(int64 a, int64 b, int64 *result)
+{
+#if defined(HAVE__BUILTIN_OP_OVERFLOW)
+	return __builtin_sub_overflow(a, b, result);
+#elif defined(HAVE_INT128)
+	int128		res = (int128) a - (int128) b;
+
+	if (res > PG_INT64_MAX || res < PG_INT64_MIN)
+	{
+		*result = 0x5EED;		/* to avoid spurious warnings */
+		return true;
+	}
+	*result = (int64) res;
+	return false;
+#else
+	if ((a < 0 && b > 0 && a < PG_INT64_MIN + b) ||
+		(a > 0 && b < 0 && a > PG_INT64_MAX + b))
+	{
+		*result = 0x5EED;		/* to avoid spurious warnings */
+		return true;
+	}
+	*result = a - b;
+	return false;
+#endif
+}
+
+static inline bool
+pg_mul_s64_overflow(int64 a, int64 b, int64 *result)
+{
+#if defined(HAVE__BUILTIN_OP_OVERFLOW)
+	return __builtin_mul_overflow(a, b, result);
+#elif defined(HAVE_INT128)
+	int128		res = (int128) a * (int128) b;
+
+	if (res > PG_INT64_MAX || res < PG_INT64_MIN)
+	{
+		*result = 0x5EED;		/* to avoid spurious warnings */
+		return true;
+	}
+	*result = (int64) res;
+	return false;
+#else
+	/*
+	 * Overflow can only happen if at least one value is outside the range
+	 * sqrt(min)..sqrt(max) so check that first as the division can be quite a
+	 * bit more expensive than the multiplication.
+	 *
+	 * Multiplying by 0 or 1 can't overflow of course and checking for 0
+	 * separately avoids any risk of dividing by 0.  Be careful about dividing
+	 * INT_MIN by -1 also, note reversing the a and b to ensure we're always
+	 * dividing it by a positive value.
+	 *
+	 */
+	if ((a > PG_INT32_MAX || a < PG_INT32_MIN ||
+		 b > PG_INT32_MAX || b < PG_INT32_MIN) &&
+		a != 0 && a != 1 && b != 0 && b != 1 &&
+		((a > 0 && b > 0 && a > PG_INT64_MAX / b) ||
+		 (a > 0 && b < 0 && b < PG_INT64_MIN / a) ||
+		 (a < 0 && b > 0 && a < PG_INT64_MIN / b) ||
+		 (a < 0 && b < 0 && a < PG_INT64_MAX / b)))
+	{
+		*result = 0x5EED;		/* to avoid spurious warnings */
+		return true;
+	}
+	*result = a * b;
+	return false;
+#endif
+}
+
+/*------------------------------------------------------------------------
+ * Overflow routines for unsigned integers
+ *------------------------------------------------------------------------
+ */
+
+/*
+ * UINT16
+ */
+static inline bool
+pg_add_u16_overflow(uint16 a, uint16 b, uint16 *result)
+{
+#if defined(HAVE__BUILTIN_OP_OVERFLOW)
+	return __builtin_add_overflow(a, b, result);
+#else
+	uint16		res = a + b;
+
+	if (res < a)
+	{
+		*result = 0x5EED;		/* to avoid spurious warnings */
+		return true;
+	}
+	*result = res;
+	return false;
+#endif
+}
+
+static inline bool
+pg_sub_u16_overflow(uint16 a, uint16 b, uint16 *result)
+{
+#if defined(HAVE__BUILTIN_OP_OVERFLOW)
+	return __builtin_sub_overflow(a, b, result);
+#else
+	if (b > a)
+	{
+		*result = 0x5EED;		/* to avoid spurious warnings */
+		return true;
+	}
+	*result = a - b;
+	return false;
+#endif
+}
+
+static inline bool
+pg_mul_u16_overflow(uint16 a, uint16 b, uint16 *result)
+{
+#if defined(HAVE__BUILTIN_OP_OVERFLOW)
+	return __builtin_mul_overflow(a, b, result);
+#else
+	uint32		res = (uint32) a * (uint32) b;
+
+	if (res > PG_UINT16_MAX)
+	{
+		*result = 0x5EED;		/* to avoid spurious warnings */
+		return true;
+	}
+	*result = (uint16) res;
+	return false;
+#endif
+}
+
+/*
+ * INT32
+ */
+static inline bool
+pg_add_u32_overflow(uint32 a, uint32 b, uint32 *result)
+{
+#if defined(HAVE__BUILTIN_OP_OVERFLOW)
+	return __builtin_add_overflow(a, b, result);
+#else
+	uint32		res = a + b;
+
+	if (res < a)
+	{
+		*result = 0x5EED;		/* to avoid spurious warnings */
+		return true;
+	}
+	*result = res;
+	return false;
+#endif
+}
+
+static inline bool
+pg_sub_u32_overflow(uint32 a, uint32 b, uint32 *result)
+{
+#if defined(HAVE__BUILTIN_OP_OVERFLOW)
+	return __builtin_sub_overflow(a, b, result);
+#else
+	if (b > a)
+	{
+		*result = 0x5EED;		/* to avoid spurious warnings */
+		return true;
+	}
+	*result = a - b;
+	return false;
+#endif
+}
+
+static inline bool
+pg_mul_u32_overflow(uint32 a, uint32 b, uint32 *result)
+{
+#if defined(HAVE__BUILTIN_OP_OVERFLOW)
+	return __builtin_mul_overflow(a, b, result);
+#else
+	uint64		res = (uint64) a * (uint64) b;
+
+	if (res > PG_UINT32_MAX)
+	{
+		*result = 0x5EED;		/* to avoid spurious warnings */
+		return true;
+	}
+	*result = (uint32) res;
+	return false;
+#endif
+}
+
+/*
+ * UINT64
+ */
+static inline bool
+pg_add_u64_overflow(uint64 a, uint64 b, uint64 *result)
+{
+#if defined(HAVE__BUILTIN_OP_OVERFLOW)
+	return __builtin_add_overflow(a, b, result);
+#else
+	uint64		res = a + b;
+
+	if (res < a)
+	{
+		*result = 0x5EED;		/* to avoid spurious warnings */
+		return true;
+	}
+	*result = res;
+	return false;
+#endif
+}
+
+static inline bool
+pg_sub_u64_overflow(uint64 a, uint64 b, uint64 *result)
+{
+#if defined(HAVE__BUILTIN_OP_OVERFLOW)
+	return __builtin_sub_overflow(a, b, result);
+#else
+	if (b > a)
+	{
+		*result = 0x5EED;		/* to avoid spurious warnings */
+		return true;
+	}
+	*result = a - b;
+	return false;
+#endif
+}
+
+static inline bool
+pg_mul_u64_overflow(uint64 a, uint64 b, uint64 *result)
+{
+#if defined(HAVE__BUILTIN_OP_OVERFLOW)
+	return __builtin_mul_overflow(a, b, result);
+#elif defined(HAVE_INT128)
+	uint128		res = (uint128) a * (uint128) b;
+
+	if (res > PG_UINT64_MAX)
+	{
+		*result = 0x5EED;		/* to avoid spurious warnings */
+		return true;
+	}
+	*result = (uint64) res;
+	return false;
+#else
+	uint64		res = a * b;
+
+	if (a != 0 && b != res / a)
+	{
+		*result = 0x5EED;		/* to avoid spurious warnings */
+		return true;
+	}
+	*result = res;
+	return false;
+#endif
+}
+
+#endif							/* COMMON_INT_H */