| /* go-type-identity.c -- hash and equality identity functions. |
| |
| Copyright 2009 The Go Authors. All rights reserved. |
| Use of this source code is governed by a BSD-style |
| license that can be found in the LICENSE file. */ |
| |
| #include <stddef.h> |
| |
| #include "runtime.h" |
| #include "go-type.h" |
| |
| /* An identity hash function for a type. This is used for types where |
| we can simply use the type value itself as a hash code. This is |
| true of, e.g., integers and pointers. */ |
| |
| uintptr_t |
| __go_type_hash_identity (const void *key, uintptr_t key_size) |
| { |
| uintptr_t ret; |
| uintptr_t i; |
| const unsigned char *p; |
| |
| if (key_size <= 8) |
| { |
| union |
| { |
| uint64 v; |
| unsigned char a[8]; |
| } u; |
| u.v = 0; |
| #ifdef WORDS_BIGENDIAN |
| __builtin_memcpy (&u.a[8 - key_size], key, key_size); |
| #else |
| __builtin_memcpy (&u.a[0], key, key_size); |
| #endif |
| if (sizeof (uintptr_t) >= 8) |
| return (uintptr_t) u.v; |
| else |
| return (uintptr_t) ((u.v >> 32) ^ (u.v & 0xffffffff)); |
| } |
| |
| ret = 5381; |
| for (i = 0, p = (const unsigned char *) key; i < key_size; i++, p++) |
| ret = ret * 33 + *p; |
| return ret; |
| } |
| |
| const FuncVal __go_type_hash_identity_descriptor = |
| { (void *) __go_type_hash_identity }; |
| |
| /* An identity equality function for a type. This is used for types |
| where we can check for equality by checking that the values have |
| the same bits. */ |
| |
| _Bool |
| __go_type_equal_identity (const void *k1, const void *k2, uintptr_t key_size) |
| { |
| return __builtin_memcmp (k1, k2, key_size) == 0; |
| } |
| |
| const FuncVal __go_type_equal_identity_descriptor = |
| { (void *) __go_type_equal_identity }; |