diff options
Diffstat (limited to 'include/ruby/internal/core/rstring.h')
| -rw-r--r-- | include/ruby/internal/core/rstring.h | 163 |
1 files changed, 19 insertions, 144 deletions
diff --git a/include/ruby/internal/core/rstring.h b/include/ruby/internal/core/rstring.h index e394ab7dca..35175ea94a 100644 --- a/include/ruby/internal/core/rstring.h +++ b/include/ruby/internal/core/rstring.h @@ -42,13 +42,7 @@ /** @cond INTERNAL_MACRO */ #define RSTRING_NOEMBED RSTRING_NOEMBED -#if !USE_RVARGC -#define RSTRING_EMBED_LEN_MASK RSTRING_EMBED_LEN_MASK -#define RSTRING_EMBED_LEN_SHIFT RSTRING_EMBED_LEN_SHIFT -#define RSTRING_EMBED_LEN_MAX RSTRING_EMBED_LEN_MAX -#endif #define RSTRING_FSTR RSTRING_FSTR -#define RSTRING_EMBED_LEN RSTRING_EMBED_LEN #define RSTRING_LEN RSTRING_LEN #define RSTRING_LENINT RSTRING_LENINT #define RSTRING_PTR RSTRING_PTR @@ -162,21 +156,6 @@ enum ruby_rstring_flags { */ RSTRING_NOEMBED = RUBY_FL_USER1, -#if !USE_RVARGC - /** - * When a string employs embedded strategy (see ::RSTRING_NOEMBED), these - * bits are used to store the number of bytes actually filled into - * ::RString::ary. - * - * @internal - * - * 3rd parties must not be aware that there even is more than one way to - * store a string. Might better be hidden. - */ - RSTRING_EMBED_LEN_MASK = RUBY_FL_USER2 | RUBY_FL_USER3 | RUBY_FL_USER4 | - RUBY_FL_USER5 | RUBY_FL_USER6, -#endif - /* Actually, string encodings are also encoded into the flags, using * remaining bits.*/ @@ -202,20 +181,6 @@ enum ruby_rstring_flags { RSTRING_FSTR = RUBY_FL_USER17 }; -#if !USE_RVARGC -/** - * This is an enum because GDB wants it (rather than a macro). People need not - * bother. - */ -enum ruby_rstring_consts { - /** Where ::RSTRING_EMBED_LEN_MASK resides. */ - RSTRING_EMBED_LEN_SHIFT = RUBY_FL_USHIFT + 2, - - /** Max possible number of characters that can be embedded. */ - RSTRING_EMBED_LEN_MAX = RBIMPL_EMBED_LEN_MAX_OF(char) - 1 -}; -#endif - /** * Ruby's String. A string in ruby conceptually has these information: * @@ -233,6 +198,13 @@ struct RString { /** Basic part, including flags and class. */ struct RBasic basic; + /** + * Length of the string, not including terminating NUL character. + * + * @note This is in bytes. + */ + long len; + /** String's specific fields. */ union { @@ -241,14 +213,6 @@ struct RString { * pattern. */ struct { - - /** - * Length of the string, not including terminating NUL character. - * - * @note This is in bytes. - */ - long len; - /** * Pointer to the contents of the string. In the old days each * string had dedicated memory regions. That is no longer true @@ -279,24 +243,12 @@ struct RString { /** Embedded contents. */ struct { -#if USE_RVARGC - long len; /* This is a length 1 array because: * 1. GCC has a bug that does not optimize C flexible array members * (https://gcc.gnu.org/bugzilla/show_bug.cgi?id=102452) * 2. Zero length arrays are not supported by all compilers */ char ary[1]; -#else - /** - * When a string is short enough, it uses this area to store the - * contents themselves. This was impractical in the 20th century, - * but these days 64 bit machines can typically hold 24 bytes here. - * Could be sufficiently large. In this case the length is encoded - * into the flags. - */ - char ary[RSTRING_EMBED_LEN_MAX + 1]; -#endif } embed; } as; }; @@ -409,81 +361,12 @@ RBIMPL_ATTR_ARTIFICIAL() * * @param[in] str String in question. * @return Its length, in bytes. - * @pre `str` must be an instance of ::RString, and must has its - * ::RSTRING_NOEMBED flag off. - * - * @internal - * - * This was a macro before. It was inevitable to be public, since macros are - * global constructs. But should it be forever? Now that it is a function, - * @shyouhei thinks it could just be eliminated, hidden into implementation - * details. - */ -static inline long -RSTRING_EMBED_LEN(VALUE str) -{ - RBIMPL_ASSERT_TYPE(str, RUBY_T_STRING); - RBIMPL_ASSERT_OR_ASSUME(! RB_FL_ANY_RAW(str, RSTRING_NOEMBED)); - -#if USE_RVARGC - long f = RSTRING(str)->as.embed.len; - return f; -#else - VALUE f = RBASIC(str)->flags; - f &= RSTRING_EMBED_LEN_MASK; - f >>= RSTRING_EMBED_LEN_SHIFT; - return RBIMPL_CAST((long)f); -#endif -} - -RBIMPL_WARNING_PUSH() -#if RBIMPL_COMPILER_IS(Intel) -RBIMPL_WARNING_IGNORED(413) -#endif - -RBIMPL_ATTR_PURE_UNLESS_DEBUG() -RBIMPL_ATTR_ARTIFICIAL() -/** - * @private - * - * "Expands" an embedded string into an ordinal one. This is a function that - * returns aggregated type. The returned struct always has its `as.heap.len` - * an `as.heap.ptr` fields set appropriately. - * - * This is an implementation detail that 3rd parties should never bother. - */ -static inline struct RString -rbimpl_rstring_getmem(VALUE str) -{ - RBIMPL_ASSERT_TYPE(str, RUBY_T_STRING); - - if (RB_FL_ANY_RAW(str, RSTRING_NOEMBED)) { - return *RSTRING(str); - } - else { - /* Expecting compilers to optimize this on-stack struct away. */ - struct RString retval; - retval.as.heap.len = RSTRING_EMBED_LEN(str); - retval.as.heap.ptr = RSTRING(str)->as.embed.ary; - return retval; - } -} - -RBIMPL_WARNING_POP() - -RBIMPL_ATTR_PURE_UNLESS_DEBUG() -RBIMPL_ATTR_ARTIFICIAL() -/** - * Queries the length of the string. - * - * @param[in] str String in question. - * @return Its length, in bytes. * @pre `str` must be an instance of ::RString. */ static inline long RSTRING_LEN(VALUE str) { - return rbimpl_rstring_getmem(str).as.heap.len; + return RSTRING(str)->len; } RBIMPL_ATTR_ARTIFICIAL() @@ -497,15 +380,13 @@ RBIMPL_ATTR_ARTIFICIAL() static inline char * RSTRING_PTR(VALUE str) { - char *ptr = rbimpl_rstring_getmem(str).as.heap.ptr; + char *ptr = RB_FL_TEST_RAW(str, RSTRING_NOEMBED) ? + RSTRING(str)->as.heap.ptr : + RSTRING(str)->as.embed.ary; - if (RB_UNLIKELY(! ptr)) { + if (RUBY_DEBUG && RB_UNLIKELY(! ptr)) { /* :BEWARE: @shyouhei thinks that currently, there are rooms for this - * function to return NULL. In the 20th century that was a pointless - * concern. However struct RString can hold fake strings nowadays. It - * seems no check against NULL are exercised around handling of them - * (one of such usages is located in marshal.c, which scares - * @shyouhei). Better check here for maximum safety. + * function to return NULL. Better check here for maximum safety. * * Also, this is not rb_warn() because RSTRING_PTR() can be called * during GC (see what obj_info() does). rb_warn() needs to allocate @@ -527,14 +408,17 @@ RBIMPL_ATTR_ARTIFICIAL() static inline char * RSTRING_END(VALUE str) { - struct RString buf = rbimpl_rstring_getmem(str); + char *ptr = RB_FL_TEST_RAW(str, RSTRING_NOEMBED) ? + RSTRING(str)->as.heap.ptr : + RSTRING(str)->as.embed.ary; + long len = RSTRING_LEN(str); - if (RB_UNLIKELY(! buf.as.heap.ptr)) { + if (RUBY_DEBUG && RB_UNLIKELY(!ptr)) { /* Ditto. */ rb_debug_rstring_null_ptr("RSTRING_END"); } - return &buf.as.heap.ptr[buf.as.heap.len]; + return &ptr[len]; } RBIMPL_ATTR_ARTIFICIAL() @@ -563,16 +447,7 @@ RSTRING_LENINT(VALUE str) * @param ptrvar Variable where its contents is stored. * @param lenvar Variable where its length is stored. */ -#ifdef HAVE_STMT_AND_DECL_IN_EXPR -# define RSTRING_GETMEM(str, ptrvar, lenvar) \ - __extension__ ({ \ - struct RString rbimpl_str = rbimpl_rstring_getmem(str); \ - (ptrvar) = rbimpl_str.as.heap.ptr; \ - (lenvar) = rbimpl_str.as.heap.len; \ - }) -#else # define RSTRING_GETMEM(str, ptrvar, lenvar) \ ((ptrvar) = RSTRING_PTR(str), \ (lenvar) = RSTRING_LEN(str)) -#endif /* HAVE_STMT_AND_DECL_IN_EXPR */ #endif /* RBIMPL_RSTRING_H */ |