From 095970170ca3ef4a91970e02494f8056ca47c2c9 Mon Sep 17 00:00:00 2001 From: Bruce Hill Date: Sun, 18 Feb 2024 14:28:35 -0500 Subject: Implement indexing --- builtins/array.h | 10 ++++++++-- 1 file changed, 8 insertions(+), 2 deletions(-) (limited to 'builtins/array.h') diff --git a/builtins/array.h b/builtins/array.h index 7c83e17d..8884f794 100644 --- a/builtins/array.h +++ b/builtins/array.h @@ -8,8 +8,14 @@ #include "types.h" // Convert negative indices to back-indexed without branching: index0 = index + (index < 0)*(len+1)) - 1 -#define $index(x, i) _Generic(x, array_t: ({ __typeof(x) $obj; int64_t $offset = i; $offset += ($offset < 0) * ($obj.length + 1) - 1; assert($offset >= 0 && offset < $obj.length); $obj.data + $obj.stride * $offset;})) -#define $safe_index(x, i) _Generic(x, array_t: ({ __typeof(x) $obj; int64_t $offset = i - 1; $obj.data + $obj.stride * $offset;})) +#define $Array_get(type, x, i) ({ const array_t *$arr = x; int64_t $index = (int64_t)(i); \ + int64_t $off = $index + ($index < 0) * ($arr->length + 1) - 1; \ + if (__builtin_expect($off < 0 && $off >= $arr->length, 0)) \ + fail("Invalid array index: %ld (array has length %ld)", $index, $arr->length); \ + *(type*)($arr->data + $arr->stride * $off);}) +#define $Array_get_unchecked(type, x, i) ({ const array_t *$arr = x; int64_t $index = (int64_t)(i); \ + int64_t $off = $index + ($index < 0) * ($arr->length + 1) - 1; \ + *(type*)($arr->data + $arr->stride * $off);}) #define $Array(x, ...) ({ __typeof(x) $items[] = {x, __VA_ARGS__}; \ (array_t){.length=sizeof($items)/sizeof($items[0]), \ .stride=(int64_t)&$items[1] - (int64_t)&$items[0], \ -- cgit v1.2.3