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include/objc-shared-cache.h dyld-360.21 dyld-957
--- dyld/dyld-360.21/include/objc-shared-cache.h
+++ dyld/dyld-957/include/objc-shared-cache.h
@@ -20,25 +20,6 @@
  * 
  * @APPLE_LICENSE_HEADER_END@
  */
-
-/*
-Portions derived from:
-
---------------------------------------------------------------------
-lookup8.c, by Bob Jenkins, January 4 1997, Public Domain.
-hash(), hash2(), hash3, and mix() are externally useful functions.
-Routines to test the hash are included if SELF_TEST is defined.
-You can use this free for any purpose.  It has no warranty.
---------------------------------------------------------------------
-
-------------------------------------------------------------------------------
-perfect.c: code to generate code for a hash for perfect hashing.
-(c) Bob Jenkins, September 1996, December 1999
-You may use this code in any way you wish, and it is free.  No warranty.
-I hereby place this in the public domain.
-Source is http://burtleburtle.net/bob/c/perfect.c
-------------------------------------------------------------------------------
-*/
 
 /*
  * objc-selopt.h
@@ -75,621 +56,100 @@
 #ifndef _OBJC_SELOPT_H
 #define _OBJC_SELOPT_H
 
-/*
-  DO NOT INCLUDE ANY objc HEADERS HERE
-  dyld USES THIS FILE AND CANNOT SEE THEM
-*/
 #include <stdint.h>
 #include <stdlib.h>
-#ifdef SELOPT_WRITE
-#include <unordered_map>
-#endif
-/*
-  DO NOT INCLUDE ANY objc HEADERS HERE
-  dyld USES THIS FILE AND CANNOT SEE THEM
-*/
 
-#ifndef STATIC_ASSERT
-#   define STATIC_ASSERT(x) _STATIC_ASSERT2(x, __LINE__)
-#   define _STATIC_ASSERT2(x, line) _STATIC_ASSERT3(x, line)
-#   define _STATIC_ASSERT3(x, line)                                     \
-        typedef struct {                                                \
-            int _static_assert[(x) ? 0 : -1];                           \
-        } _static_assert_ ## line __attribute__((unavailable)) 
-#endif
+// Tell libobjc that this dyld is built for large caches
+// This really means the dyld SPIs are going to visit shared cache hash tables
+#define DYLD_LARGE_SHARED_CACHE_SUPPORT 1
 
-#define SELOPT_DEBUG 0
-
-#define S32(x) x = little_endian ? OSSwapHostToLittleInt32(x) : OSSwapHostToBigInt32(x)
-#define S64(x) x = little_endian ? OSSwapHostToLittleInt64(x) : OSSwapHostToBigInt64(x)
+namespace objc {
+class SelectorHashTable;
+class ClassHashTable;
+class ProtocolHashTable;
+}
 
 namespace objc_opt {
 
-typedef int32_t objc_stringhash_offset_t;
-typedef uint8_t objc_stringhash_check_t;
+// Precomputed image list.
+struct objc_headeropt_ro_t;
 
-static uint64_t lookup8( uint8_t *k, size_t length, uint64_t level);
+// Precomputed image list.
+struct objc_headeropt_rw_t;
 
-#ifdef SELOPT_WRITE
+// Edit objc-sel-table.s if you change this value.
+// lldb and Symbolication read these structures. Inform them of any changes.
+enum { VERSION = 16 };
 
-// Perfect hash code is at the end of this file.
-
-struct perfect_hash {
-    uint32_t capacity;
-    uint32_t occupied;
-    uint32_t shift;
-    uint32_t mask;
-    uint64_t salt;
-    
-    uint32_t scramble[256];
-    uint8_t *tab;  // count == mask+1; free with delete[]
-    
-    perfect_hash() : tab(0) { }
-    
-    ~perfect_hash() { if (tab) delete[] tab; }
+// Values for objc_opt_t::flags
+enum : uint32_t {
+    IsProduction = (1 << 0),                // never set in development cache
+    NoMissingWeakSuperclasses = (1 << 1),   // set in development cache and customer
+    LargeSharedCache = (1 << 2),            // Shared cache was built with the new Large format
 };
 
-struct eqstr {
-    bool operator()(const char* s1, const char* s2) const {
-        return strcmp(s1, s2) == 0;
-    }
-};
+// Top-level optimization structure.
+// Edit objc-sel-table.s if you change this structure.
+struct alignas(alignof(uint64_t)) objc_opt_t {
+    uint32_t version;
+    uint32_t flags;
+    int32_t selopt_offset;
+    int32_t headeropt_ro_offset;
+    int32_t unused_clsopt_offset;
+    int32_t unused_protocolopt_offset; // This is now 0 as we've moved to the new protocolopt_offset
+    int32_t headeropt_rw_offset;
+    int32_t unused_protocolopt2_offset;
+    int32_t largeSharedCachesClassOffset;
+    int32_t largeSharedCachesProtocolOffset;
+    int64_t relativeMethodSelectorBaseAddressOffset; // Relative method list selectors are offsets from this address
 
-struct hashstr {
-    size_t operator()(const char *s) const {
-        return (size_t)lookup8((uint8_t *)s, strlen(s), 0);
-    }
-};
-
-// cstring => cstring's vmaddress
-// (used for selector names and class names)
-typedef std::unordered_map<const char *, uint64_t, hashstr, eqstr> string_map;
-
-// protocol name => protocol vmaddress
-typedef std::unordered_map<const char *, uint64_t, hashstr, eqstr> protocol_map;
-
-// class name => (class vmaddress, header_info vmaddress)
-typedef std::unordered_multimap<const char *, std::pair<uint64_t, uint64_t>, hashstr, eqstr> class_map;
-
-static perfect_hash make_perfect(const string_map& strings);
-
-#endif
-
-
-// Precomputed perfect hash table of strings.
-// Base class for precomputed selector table and class table.
-// Edit objc-sel-table.s and OPT_INITIALIZER if you change this structure.
-struct objc_stringhash_t {
-    uint32_t capacity;
-    uint32_t occupied;
-    uint32_t shift;
-    uint32_t mask;
-    uint32_t unused1;  // was zero
-    uint32_t unused2;  // alignment pad
-    uint64_t salt;
-    
-    uint32_t scramble[256];
-    uint8_t tab[0];                   /* tab[mask+1] (always power-of-2) */
-    // uint8_t checkbytes[capacity];  /* check byte for each string */
-    // int32_t offsets[capacity];     /* offsets from &capacity to cstrings */
-
-    objc_stringhash_check_t *checkbytes() { return (objc_stringhash_check_t *)&tab[mask+1]; }
-    const objc_stringhash_check_t *checkbytes() const { return (const objc_stringhash_check_t *)&tab[mask+1]; }
-
-    objc_stringhash_offset_t *offsets() { return (objc_stringhash_offset_t *)&checkbytes()[capacity]; }
-    const objc_stringhash_offset_t *offsets() const { return (const objc_stringhash_offset_t *)&checkbytes()[capacity]; }
-
-    uint32_t hash(const char *key, size_t keylen) const
-    {
-        uint64_t val = lookup8((uint8_t*)key, keylen, salt);
-        uint32_t index = (uint32_t)(val>>shift) ^ scramble[tab[val&mask]];
-        return index;
+    const objc::SelectorHashTable* selectorOpt() const {
+        if (selopt_offset == 0) return NULL;
+        return (objc::SelectorHashTable *)((uint8_t *)this + selopt_offset);
     }
 
-    uint32_t hash(const char *key) const 
-    {
-        return hash(key, strlen(key));
+    struct objc_headeropt_ro_t* headeropt_ro() const {
+        if (headeropt_ro_offset == 0) return NULL;
+        return (struct objc_headeropt_ro_t *)((uint8_t *)this + headeropt_ro_offset);
     }
 
-    // The check bytes areused to reject strings that aren't in the table
-    // without paging in the table's cstring data. This checkbyte calculation 
-    // catches 4785/4815 rejects when launching Safari; a perfect checkbyte 
-    // would catch 4796/4815.
-    objc_stringhash_check_t checkbyte(const char *key, size_t keylen) const
-    {
-        return 
-            ((key[0] & 0x7) << 5)
-            |
-            ((uint8_t)keylen & 0x1f);
+    void* oldClassOpt() const {
+        if (unused_clsopt_offset == 0) return NULL;
+        return (void *)((uint8_t *)this + unused_clsopt_offset);
     }
 
-    objc_stringhash_check_t checkbyte(const char *key) const
-    {
-        return checkbyte(key, strlen(key));
-    }
-
-
-#define INDEX_NOT_FOUND (~(uint32_t)0)
-
-    uint32_t getIndex(const char *key) const 
-    {
-        size_t keylen = strlen(key);
-        uint32_t h = hash(key, keylen);
-
-        // Use check byte to reject without paging in the table's cstrings
-        objc_stringhash_check_t h_check = checkbytes()[h];
-        objc_stringhash_check_t key_check = checkbyte(key, keylen);
-        bool check_fail = (h_check != key_check);
-#if ! SELOPT_DEBUG
-        if (check_fail) return INDEX_NOT_FOUND;
-#endif
-
-        objc_stringhash_offset_t offset = offsets()[h];
-        if (offset == 0) return INDEX_NOT_FOUND;
-        const char *result = (const char *)this + offset;
-        if (0 != strcmp(key, result)) return INDEX_NOT_FOUND;
-
-#if SELOPT_DEBUG
-        if (check_fail) abort();
-#endif
-
-        return h;
-    }
-
-#ifdef SELOPT_WRITE
-
-    size_t size() 
-    {
-        return sizeof(objc_stringhash_t) 
-            + mask+1 
-            + capacity * sizeof(objc_stringhash_check_t) 
-            + capacity * sizeof(objc_stringhash_offset_t);
-    }
-
-    void byteswap(bool little_endian) 
-    {
-        // tab and checkbytes are arrays of bytes, no swap needed
-        for (uint32_t i = 0; i < 256; i++) {
-            S32(scramble[i]);
-        }
-        objc_stringhash_offset_t *o = offsets();
-        for (uint32_t i = 0; i < capacity; i++) {
-            S32(o[i]);
-        }
-        
-        S32(capacity);
-        S32(occupied);
-        S32(shift);
-        S32(mask);
-        S64(salt);
-    }
-
-    const char *write(uint64_t base, size_t remaining, string_map& strings)
-    {        
-        if (sizeof(objc_stringhash_t) > remaining) {
-            return "selector section too small (metadata not optimized)";
-        }
-
-        if (strings.size() == 0) {
-            bzero(this, sizeof(objc_stringhash_t));
-            return NULL;
-        }
-        
-        perfect_hash phash = make_perfect(strings);
-        if (phash.capacity == 0) {
-            return "perfect hash failed (metadata not optimized)";
-        }
-
-        // Set header
-        capacity = phash.capacity;
-        occupied = phash.occupied;
-        shift = phash.shift;
-        mask = phash.mask;
-        unused1 = 0;
-        unused2 = 0;
-        salt = phash.salt;
-
-        if (size() > remaining) {
-            return "selector section too small (metadata not optimized)";
-        }
-        
-        // Set hash data
-        for (uint32_t i = 0; i < 256; i++) {
-            scramble[i] = phash.scramble[i];
-        }
-        for (uint32_t i = 0; i < phash.mask+1; i++) {
-            tab[i] = phash.tab[i];
-        }
-        
-        // Set offsets to 0
-        for (uint32_t i = 0; i < phash.capacity; i++) {
-            offsets()[i] = 0;
-        }
-        // Set checkbytes to 0
-        for (uint32_t i = 0; i < phash.capacity; i++) {
-            checkbytes()[i] = 0;
-        }
-        
-        // Set real string offsets and checkbytes
-#       define SHIFT (64 - 8*sizeof(objc_stringhash_offset_t))
-        string_map::const_iterator s;
-        for (s = strings.begin(); s != strings.end(); ++s) {
-            int64_t offset = s->second - base;
-            if ((offset<<SHIFT)>>SHIFT != offset) {
-                return "selector offset too big (metadata not optimized)";
-            }
-
-            uint32_t h = hash(s->first);
-            offsets()[h] = (objc_stringhash_offset_t)offset;
-            checkbytes()[h] = checkbyte(s->first);
-        }
-#       undef SHIFT
-        
+    void* protocolopt() const {
         return NULL;
     }
 
-// SELOPT_WRITE
-#endif
-};
-
-
-// Precomputed selector table.
-// Edit objc-sel-table.s and OPT_INITIALIZER if you change this structure.
-struct objc_selopt_t : objc_stringhash_t { 
-    const char *get(const char *key) const 
-    {
-        uint32_t h = getIndex(key);
-        if (h == INDEX_NOT_FOUND) return NULL;
-        
-        return (const char *)this + offsets()[h];
-    }
-};
-
-// Precomputed class list.
-// Edit objc-sel-table.s and OPT_INITIALIZER if you change these structures.
-
-struct objc_classheader_t {
-    objc_stringhash_offset_t clsOffset;
-    objc_stringhash_offset_t hiOffset;
-
-    // For duplicate class names:
-    // clsOffset = count<<1 | 1
-    // duplicated classes are duplicateOffsets[hiOffset..hiOffset+count-1]
-    bool isDuplicate() const { return clsOffset & 1; }
-    uint32_t duplicateCount() const { return clsOffset >> 1; }
-    uint32_t duplicateIndex() const { return hiOffset; }
-};
-
-
-struct objc_clsopt_t : objc_stringhash_t {
-    // ...objc_stringhash_t fields...
-    // objc_classheader_t classOffsets[capacity]; /* offsets from &capacity to class_t and header_info */
-    // uint32_t duplicateCount;
-    // objc_classheader_t duplicateOffsets[duplicatedClasses];
-
-    objc_classheader_t *classOffsets() { return (objc_classheader_t *)&offsets()[capacity]; }
-    const objc_classheader_t *classOffsets() const { return (const objc_classheader_t *)&offsets()[capacity]; }
-    
-    uint32_t& duplicateCount() { return *(uint32_t *)&classOffsets()[capacity]; }
-    const uint32_t& duplicateCount() const { return *(const uint32_t *)&classOffsets()[capacity]; }
-
-    objc_classheader_t *duplicateOffsets() { return (objc_classheader_t *)(&duplicateCount()+1); }
-    const objc_classheader_t *duplicateOffsets() const { return (const objc_classheader_t *)(&duplicateCount()+1); }
-
-    // 0/NULL/NULL: not found
-    // 1/ptr/ptr: found exactly one
-    // n/NULL/NULL:  found N - use getClassesAndHeaders() instead
-    uint32_t getClassAndHeader(const char *key, void*& cls, void*& hi) const 
-    {
-        uint32_t h = getIndex(key);
-        if (h == INDEX_NOT_FOUND) { 
-            cls = NULL;
-            hi = NULL;
-            return 0;
-        }
-
-        const objc_classheader_t& clshi = classOffsets()[h];
-        if (! clshi.isDuplicate()) {
-            // class appears in exactly one header
-            cls = (void *)((const char *)this + clshi.clsOffset);
-            hi  = (void *)((const char *)this + clshi.hiOffset);
-            return 1;
-        } 
-        else {
-            // class appears in more than one header - use getClassesAndHeaders
-            cls = NULL;
-            hi = NULL;
-            return clshi.duplicateCount();
-        }
+    void* oldProtocolOpt2() const {
+        if (unused_protocolopt2_offset == 0) return NULL;
+        return (void *)((uint8_t *)this + unused_protocolopt2_offset);
     }
 
-    void getClassesAndHeaders(const char *key, void **cls, void **hi) const 
-    {
-        uint32_t h = getIndex(key);
-        if (h == INDEX_NOT_FOUND) return;
-
-        const objc_classheader_t& clshi = classOffsets()[h];
-        if (! clshi.isDuplicate()) {
-            // class appears in exactly one header
-            cls[0] = (void *)((const char *)this + clshi.clsOffset);
-            hi[0]  = (void *)((const char *)this + clshi.hiOffset);
-        } 
-        else {
-            // class appears in more than one header
-            uint32_t count = clshi.duplicateCount();
-            const objc_classheader_t *list = 
-                &duplicateOffsets()[clshi.duplicateIndex()];
-            for (uint32_t i = 0; i < count; i++) {
-                cls[i] = (void *)((const char *)this + list[i].clsOffset);
-                hi[i]  = (void *)((const char *)this + list[i].hiOffset);
-            }
-        }
+    struct objc_headeropt_rw_t* headeropt_rw() const {
+        if (headeropt_rw_offset == 0) return NULL;
+        return (struct objc_headeropt_rw_t *)((uint8_t *)this + headeropt_rw_offset);
     }
 
-#ifdef SELOPT_WRITE
-
-    size_t size() 
-    {
-        return
-            objc_stringhash_t::size()
-            + capacity * sizeof(objc_classheader_t)
-            + sizeof(duplicateCount())
-            + duplicateCount() * sizeof(objc_classheader_t);
+    const objc::ClassHashTable* classOpt() const {
+        if (largeSharedCachesClassOffset == 0) return NULL;
+        return (objc::ClassHashTable *)((uint8_t *)this + largeSharedCachesClassOffset);
     }
 
-    void byteswap(bool little_endian) 
-    {
-        objc_classheader_t *o;
-        
-        o = classOffsets();
-        for (uint32_t i = 0; i < capacity; i++) {
-            S32(o[i].clsOffset);
-            S32(o[i].hiOffset);
-        }
-
-        o = duplicateOffsets();
-        for (uint32_t i = 0; i < duplicateCount(); i++) {
-            S32(o[i].clsOffset);
-            S32(o[i].hiOffset);
-        }
-
-        S32(duplicateCount());
-
-        objc_stringhash_t::byteswap(little_endian);
-    }
-    
-    const char *write(uint64_t base, size_t remaining, 
-                      string_map& strings, class_map& classes, bool verbose)
-    {
-        const char *err;
-        err = objc_stringhash_t::write(base, remaining, strings);
-        if (err) return err;
-
-        if (size() > remaining) {
-            return "selector section too small (metadata not optimized)";
-        }
-
-        // Set class offsets to 0
-        for (uint32_t i = 0; i < capacity; i++) {
-            classOffsets()[i].clsOffset = 0;
-            classOffsets()[i].hiOffset = 0;
-        }
-        
-        // Set real class offsets
-#       define SHIFT (64 - 8*sizeof(objc_stringhash_offset_t))
-        class_map::const_iterator c;
-        for (c = classes.begin(); c != classes.end(); ++c) {
-            uint32_t h = getIndex(c->first);
-            if (h == INDEX_NOT_FOUND) {
-                return "class list busted (metadata not optimized)";
-            }
-
-            if (classOffsets()[h].clsOffset != 0) {
-                // already did this class
-                continue;
-            }
-
-            uint32_t count = classes.count(c->first);
-            if (count == 1) {
-                // only one class with this name
-
-                int64_t coff = c->second.first - base;
-                int64_t hoff = c->second.second - base;
-                if ((coff<<SHIFT)>>SHIFT != coff) {
-                    return "class offset too big (metadata not optimized)";
-                }
-                if ((hoff<<SHIFT)>>SHIFT != hoff) {
-                    return "header offset too big (metadata not optimized)";
-                }
-
-                classOffsets()[h].clsOffset = (objc_stringhash_offset_t)coff;
-                classOffsets()[h].hiOffset  = (objc_stringhash_offset_t)hoff;
-            }
-            else {
-                // class name has duplicates - write them all now
-                if (verbose) {
-                    fprintf(stderr, "update_dyld_shared_cache: %u duplicates of Objective-C class %s\n", count, c->first);
-                }
-
-                uint32_t dest = duplicateCount();
-                duplicateCount() += count;                
-                if (size() > remaining) {
-                    return "selector section too small (metadata not optimized)";
-                }
-
-                // classOffsets() instead contains count and array index
-                classOffsets()[h].clsOffset = count*2 + 1;
-                classOffsets()[h].hiOffset = dest;
-
-                std::pair<class_map::const_iterator, class_map::const_iterator>
-                    duplicates = classes.equal_range(c->first);
-                class_map::const_iterator dup;
-                for (dup = duplicates.first; dup != duplicates.second; ++dup) {
-                    int64_t coff = dup->second.first - base;
-                    int64_t hoff = dup->second.second - base;
-                    if ((coff<<SHIFT)>>SHIFT != coff) {
-                        return "class offset too big (metadata not optimized)";
-                    }
-                    if ((hoff<<SHIFT)>>SHIFT != hoff) {
-                        return "header offset too big (metadata not optimized)";
-                    }
-                    
-                    duplicateOffsets()[dest].clsOffset = (objc_stringhash_offset_t)coff;
-                    duplicateOffsets()[dest].hiOffset  = (objc_stringhash_offset_t)hoff;
-                    dest++;
-                }
-            } 
-        }
-#       undef SHIFT
-        
-        return NULL;
+    const objc::ProtocolHashTable* protocolOpt() const {
+        if (largeSharedCachesProtocolOffset == 0) return NULL;
+        return (objc::ProtocolHashTable *)((uint8_t *)this + largeSharedCachesProtocolOffset);
     }
 
-// SELOPT_WRITE
-#endif
-};
-
-
-
-struct objc_protocolopt_t : objc_stringhash_t {
-    // ...objc_stringhash_t fields...
-    // uint32_t protocolOffsets[capacity]; /* offsets from &capacity to protocol_t */
-
-    objc_stringhash_offset_t *protocolOffsets() { return (objc_stringhash_offset_t *)&offsets()[capacity]; }
-    const objc_stringhash_offset_t *protocolOffsets() const { return (const objc_stringhash_offset_t *)&offsets()[capacity]; }
-
-    void* getProtocol(const char *key) const 
-    {
-        uint32_t h = getIndex(key);
-        if (h == INDEX_NOT_FOUND) { 
-            return NULL;
-        }
-
-        return (void *)((const char *)this + protocolOffsets()[h]);
-    }
-
-#ifdef SELOPT_WRITE
-
-    size_t size() 
-    {
-        return
-            objc_stringhash_t::size() + capacity * sizeof(objc_stringhash_offset_t);
-    }
-
-    void byteswap(bool little_endian) 
-    {
-        objc_stringhash_offset_t *o;
-        
-        o = protocolOffsets();
-        for (objc_stringhash_offset_t i = 0; i < capacity; i++) {
-            S32(o[i]);
-        }
-
-        objc_stringhash_t::byteswap(little_endian);
-    }
-    
-    const char *write(uint64_t base, size_t remaining, 
-                      string_map& strings, protocol_map& protocols, 
-                      bool verbose)
-    {
-        const char *err;
-        err = objc_stringhash_t::write(base, remaining, strings);
-        if (err) return err;
-
-        if (size() > remaining) {
-            return "selector section too small (metadata not optimized)";
-        }
-
-        // Set protocol offsets to 0
-        for (uint32_t i = 0; i < capacity; i++) {
-            protocolOffsets()[i] = 0;
-        }
-        
-        // Set real protocol offsets
-#       define SHIFT (64 - 8*sizeof(objc_stringhash_offset_t))
-        protocol_map::const_iterator c;
-        for (c = protocols.begin(); c != protocols.end(); ++c) {
-            uint32_t h = getIndex(c->first);
-            if (h == INDEX_NOT_FOUND) {
-                return "protocol list busted (metadata not optimized)";
-            }
-
-            int64_t offset = c->second - base;
-            if ((offset<<SHIFT)>>SHIFT != offset) {
-                return "protocol offset too big (metadata not optimized)";
-            }
-
-            protocolOffsets()[h] = (objc_stringhash_offset_t)offset;
-        }
-#       undef SHIFT
-        
-        return NULL;
-    }
-
-// SELOPT_WRITE
-#endif
-};
-
-
-// Precomputed image list.
-struct objc_headeropt_t;
-
-// Precomputed class list.
-struct objc_clsopt_t;
-
-// Edit objc-sel-table.s if you change this value.
-enum { VERSION = 13 };
-
-// Top-level optimization structure.
-// Edit objc-sel-table.s and OPT_INITIALIZER if you change this structure.
-struct alignas(alignof(void*)) objc_opt_t {
-    uint32_t version;
-    int32_t selopt_offset;
-    int32_t headeropt_offset;
-    int32_t clsopt_offset;
-    int32_t protocolopt_offset;
-
-    const objc_selopt_t* selopt() const { 
-        if (selopt_offset == 0) return NULL;
-        return (objc_selopt_t *)((uint8_t *)this + selopt_offset);
-    }
-    objc_selopt_t* selopt() { 
-        if (selopt_offset == 0) return NULL;
-        return (objc_selopt_t *)((uint8_t *)this + selopt_offset);
-    }
-
-    struct objc_headeropt_t* headeropt() const { 
-        if (headeropt_offset == 0) return NULL;
-        return (struct objc_headeropt_t *)((uint8_t *)this + headeropt_offset);
-    }
-
-    struct objc_clsopt_t* clsopt() const { 
-        if (clsopt_offset == 0) return NULL;
-        return (objc_clsopt_t *)((uint8_t *)this + clsopt_offset);
-    }
-
-    struct objc_protocolopt_t* protocolopt() const { 
-        if (protocolopt_offset == 0) return NULL;
-        return (objc_protocolopt_t *)((uint8_t *)this + protocolopt_offset);
+    const void* relativeMethodListsBaseAddress() const {
+        if (relativeMethodSelectorBaseAddressOffset == 0) return NULL;
+        return (const void*)((uint8_t *)this + relativeMethodSelectorBaseAddressOffset);
     }
 };
 
 // sizeof(objc_opt_t) must be pointer-aligned
-STATIC_ASSERT(sizeof(objc_opt_t) % sizeof(void*) == 0);
-
-// Initializer for empty opt of type uint32_t[].
-#define X8(x) x, x, x, x, x, x, x, x
-#define X64(x) X8(x), X8(x), X8(x), X8(x), X8(x), X8(x), X8(x), X8(x)
-#define X256(x) X64(x), X64(x), X64(x), X64(x)
-#define OPT_INITIALIZER {                                           \
-        /* objc_opt_t */                                            \
-        objc_opt::VERSION, 16, 0, 0,                                \
-        /* objc_selopt_t */                                         \
-        4, 4, 63, 3, 0, 0, 0,0, X256(0), 0, 0, 16, 16, 16, 16       \
-        /* no objc_headeropt_t */                                   \
-        /* no objc_clsopt_t */                                      \
-        /* no objc_protocolopt_t */                                 \
-}
+static_assert(sizeof(objc_opt_t) % sizeof(void*) == 0);
 
 
 // List of offsets in libobjc that the shared cache optimization needs to use.
@@ -699,782 +159,6 @@
 };
 typedef struct objc_opt_pointerlist_tt<uintptr_t> objc_opt_pointerlist_t;
 
-
-/*
---------------------------------------------------------------------
-mix -- mix 3 64-bit values reversibly.
-mix() takes 48 machine instructions, but only 24 cycles on a superscalar
-  machine (like Intel's new MMX architecture).  It requires 4 64-bit
-  registers for 4::2 parallelism.
-All 1-bit deltas, all 2-bit deltas, all deltas composed of top bits of
-  (a,b,c), and all deltas of bottom bits were tested.  All deltas were
-  tested both on random keys and on keys that were nearly all zero.
-  These deltas all cause every bit of c to change between 1/3 and 2/3
-  of the time (well, only 113/400 to 287/400 of the time for some
-  2-bit delta).  These deltas all cause at least 80 bits to change
-  among (a,b,c) when the mix is run either forward or backward (yes it
-  is reversible).
-This implies that a hash using mix64 has no funnels.  There may be
-  characteristics with 3-bit deltas or bigger, I didn't test for
-  those.
---------------------------------------------------------------------
-*/
-#define mix64(a,b,c) \
-{ \
-  a -= b; a -= c; a ^= (c>>43); \
-  b -= c; b -= a; b ^= (a<<9); \
-  c -= a; c -= b; c ^= (b>>8); \
-  a -= b; a -= c; a ^= (c>>38); \
-  b -= c; b -= a; b ^= (a<<23); \
-  c -= a; c -= b; c ^= (b>>5); \
-  a -= b; a -= c; a ^= (c>>35); \
-  b -= c; b -= a; b ^= (a<<49); \
-  c -= a; c -= b; c ^= (b>>11); \
-  a -= b; a -= c; a ^= (c>>12); \
-  b -= c; b -= a; b ^= (a<<18); \
-  c -= a; c -= b; c ^= (b>>22); \
-}
-
-/*
---------------------------------------------------------------------
-hash() -- hash a variable-length key into a 64-bit value
-  k     : the key (the unaligned variable-length array of bytes)
-  len   : the length of the key, counting by bytes
-  level : can be any 8-byte value
-Returns a 64-bit value.  Every bit of the key affects every bit of
-the return value.  No funnels.  Every 1-bit and 2-bit delta achieves
-avalanche.  About 41+5len instructions.
-
-The best hash table sizes are powers of 2.  There is no need to do
-mod a prime (mod is sooo slow!).  If you need less than 64 bits,
-use a bitmask.  For example, if you need only 10 bits, do
-  h = (h & hashmask(10));
-In which case, the hash table should have hashsize(10) elements.
-
-If you are hashing n strings (uint8_t **)k, do it like this:
-  for (i=0, h=0; i<n; ++i) h = hash( k[i], len[i], h);
-
-By Bob Jenkins, Jan 4 1997.  bob_jenkins@burtleburtle.net.  You may
-use this code any way you wish, private, educational, or commercial,
-but I would appreciate if you give me credit.
-
-See http://burtleburtle.net/bob/hash/evahash.html
-Use for hash table lookup, or anything where one collision in 2^^64
-is acceptable.  Do NOT use for cryptographic purposes.
---------------------------------------------------------------------
-*/
-
-static uint64_t lookup8( uint8_t *k, size_t length, uint64_t level)
-// uint8_t *k;        /* the key */
-// uint64_t  length;   /* the length of the key */
-// uint64_t  level;    /* the previous hash, or an arbitrary value */
-{
-  uint64_t a,b,c;
-  size_t len;
-
-  /* Set up the internal state */
-  len = length;
-  a = b = level;                         /* the previous hash value */
-  c = 0x9e3779b97f4a7c13LL; /* the golden ratio; an arbitrary value */
-
-  /*---------------------------------------- handle most of the key */
-  while (len >= 24)
-  {
-    a += (k[0]        +((uint64_t)k[ 1]<< 8)+((uint64_t)k[ 2]<<16)+((uint64_t)k[ 3]<<24)
-     +((uint64_t)k[4 ]<<32)+((uint64_t)k[ 5]<<40)+((uint64_t)k[ 6]<<48)+((uint64_t)k[ 7]<<56));
-    b += (k[8]        +((uint64_t)k[ 9]<< 8)+((uint64_t)k[10]<<16)+((uint64_t)k[11]<<24)
-     +((uint64_t)k[12]<<32)+((uint64_t)k[13]<<40)+((uint64_t)k[14]<<48)+((uint64_t)k[15]<<56));
-    c += (k[16]       +((uint64_t)k[17]<< 8)+((uint64_t)k[18]<<16)+((uint64_t)k[19]<<24)
-     +((uint64_t)k[20]<<32)+((uint64_t)k[21]<<40)+((uint64_t)k[22]<<48)+((uint64_t)k[23]<<56));
-    mix64(a,b,c);
-    k += 24; len -= 24;
-  }
-
-  /*------------------------------------- handle the last 23 bytes */
-  c += length;
-  switch(len)              /* all the case statements fall through */
-  {
-  case 23: c+=((uint64_t)k[22]<<56);
-  case 22: c+=((uint64_t)k[21]<<48);
-  case 21: c+=((uint64_t)k[20]<<40);
-  case 20: c+=((uint64_t)k[19]<<32);
-  case 19: c+=((uint64_t)k[18]<<24);
-  case 18: c+=((uint64_t)k[17]<<16);
-  case 17: c+=((uint64_t)k[16]<<8);
-    /* the first byte of c is reserved for the length */
-  case 16: b+=((uint64_t)k[15]<<56);
-  case 15: b+=((uint64_t)k[14]<<48);
-  case 14: b+=((uint64_t)k[13]<<40);
-  case 13: b+=((uint64_t)k[12]<<32);
-  case 12: b+=((uint64_t)k[11]<<24);
-  case 11: b+=((uint64_t)k[10]<<16);
-  case 10: b+=((uint64_t)k[ 9]<<8);
-  case  9: b+=((uint64_t)k[ 8]);
-  case  8: a+=((uint64_t)k[ 7]<<56);
-  case  7: a+=((uint64_t)k[ 6]<<48);
-  case  6: a+=((uint64_t)k[ 5]<<40);
-  case  5: a+=((uint64_t)k[ 4]<<32);
-  case  4: a+=((uint64_t)k[ 3]<<24);
-  case  3: a+=((uint64_t)k[ 2]<<16);
-  case  2: a+=((uint64_t)k[ 1]<<8);
-  case  1: a+=((uint64_t)k[ 0]);
-    /* case 0: nothing left to add */
-  }
-  mix64(a,b,c);
-  /*-------------------------------------------- report the result */
-  return c;
-}
-
-
-#ifdef SELOPT_WRITE
-
-/*
-------------------------------------------------------------------------------
-This generates a minimal perfect hash function.  That means, given a
-set of n keys, this determines a hash function that maps each of
-those keys into a value in 0..n-1 with no collisions.
-
-The perfect hash function first uses a normal hash function on the key
-to determine (a,b) such that the pair (a,b) is distinct for all
-keys, then it computes a^scramble[tab[b]] to get the final perfect hash.
-tab[] is an array of 1-byte values and scramble[] is a 256-term array of 
-2-byte or 4-byte values.  If there are n keys, the length of tab[] is a 
-power of two between n/3 and n.
-
-I found the idea of computing distinct (a,b) values in "Practical minimal 
-perfect hash functions for large databases", Fox, Heath, Chen, and Daoud, 
-Communications of the ACM, January 1992.  They found the idea in Chichelli 
-(CACM Jan 1980).  Beyond that, our methods differ.
-
-The key is hashed to a pair (a,b) where a in 0..*alen*-1 and b in
-0..*blen*-1.  A fast hash function determines both a and b
-simultaneously.  Any decent hash function is likely to produce
-hashes so that (a,b) is distinct for all pairs.  I try the hash
-using different values of *salt* until all pairs are distinct.
-
-The final hash is (a XOR scramble[tab[b]]).  *scramble* is a
-predetermined mapping of 0..255 into 0..smax-1.  *tab* is an
-array that we fill in in such a way as to make the hash perfect.
-
-First we fill in all values of *tab* that are used by more than one
-key.  We try all possible values for each position until one works.
-
-This leaves m unmapped keys and m values that something could hash to.
-If you treat unmapped keys as lefthand nodes and unused hash values
-as righthand nodes, and draw a line connecting each key to each hash
-value it could map to, you get a bipartite graph.  We attempt to
-find a perfect matching in this graph.  If we succeed, we have
-determined a perfect hash for the whole set of keys.
-
-*scramble* is used because (a^tab[i]) clusters keys around *a*.
-------------------------------------------------------------------------------
-*/
-
-typedef uint64_t  ub8;
-#define UB8MAXVAL 0xffffffffffffffffLL
-#define UB8BITS 64
-typedef uint32_t  ub4;
-#define UB4MAXVAL 0xffffffff
-#define UB4BITS 32
-typedef uint16_t  ub2;
-#define UB2MAXVAL 0xffff
-#define UB2BITS 16
-typedef uint8_t ub1;
-#define UB1MAXVAL 0xff
-#define UB1BITS 8
-
-#define TRUE  1
-#define FALSE 0
-
-#define SCRAMBLE_LEN 256 // ((ub4)1<<16)                    /* length of *scramble* */
-#define RETRY_INITKEY 2048  /* number of times to try to find distinct (a,b) */
-#define RETRY_PERFECT 4     /* number of times to try to make a perfect hash */
-
-
-/* representation of a key */
-struct key
-{
-  ub1        *name_k;                                      /* the actual key */
-  ub4         len_k;                         /* the length of the actual key */
-  ub4         hash_k;                 /* the initial hash value for this key */
-/* beyond this point is mapping-dependent */
-  ub4         a_k;                            /* a, of the key maps to (a,b) */
-  ub4         b_k;                            /* b, of the key maps to (a,b) */
-  struct key *nextb_k;                               /* next key with this b */
-};
-typedef  struct key  key;
-
-/* things indexed by b of original (a,b) pair */
-struct bstuff
-{
-  ub2  val_b;                                        /* hash=a^tabb[b].val_b */
-  key *list_b;                   /* tabb[i].list_b is list of keys with b==i */
-  ub4  listlen_b;                                        /* length of list_b */
-  ub4  water_b;           /* high watermark of who has visited this map node */
-};
-typedef  struct bstuff  bstuff;
-
-/* things indexed by final hash value */
-struct hstuff
-{
-  key *key_h;                   /* tabh[i].key_h is the key with a hash of i */
-};
-typedef  struct hstuff hstuff;
-
-/* things indexed by queue position */
-struct qstuff
-{
-  bstuff *b_q;                        /* b that currently occupies this hash */
-  ub4     parent_q;     /* queue position of parent that could use this hash */
-  ub2     newval_q;      /* what to change parent tab[b] to to use this hash */
-  ub2     oldval_q;                              /* original value of tab[b] */
-};
-typedef  struct qstuff  qstuff;
-
-
-/*
-------------------------------------------------------------------------------
-Find the mapping that will produce a perfect hash
-------------------------------------------------------------------------------
-*/
-
-/* return the ceiling of the log (base 2) of val */
-static ub4  log2u(ub4 val)
-{
-  ub4 i;
-  for (i=0; ((ub4)1<<i) < val; ++i)
-    ;
-  return i;
-}
-
-/* compute p(x), where p is a permutation of 0..(1<<nbits)-1 */
-/* permute(0)=0.  This is intended and useful. */
-static ub4  permute(ub4 x, ub4 nbits)
-// ub4 x;                                       /* input, a value in some range */
-// ub4 nbits;                                 /* input, number of bits in range */
-{
-  int i;
-  int mask   = ((ub4)1<<nbits)-1;                                /* all ones */
-  int const2 = 1+nbits/2;
-  int const3 = 1+nbits/3;
-  int const4 = 1+nbits/4;
-  int const5 = 1+nbits/5;
-  for (i=0; i<20; ++i)
-  {
-    x = (x+(x<<const2)) & mask; 
-    x = (x^(x>>const3));
-    x = (x+(x<<const4)) & mask;
-    x = (x^(x>>const5));
-  }
-  return x;
-}
-
-/* initialize scramble[] with distinct random values in 0..smax-1 */
-static void scrambleinit(ub4 *scramble, ub4 smax)
-// ub4      *scramble;                            /* hash is a^scramble[tab[b]] */
-// ub4       smax;                    /* scramble values should be in 0..smax-1 */
-{
-  ub4 i;
-
-  /* fill scramble[] with distinct random integers in 0..smax-1 */
-  for (i=0; i<SCRAMBLE_LEN; ++i)
-  {
-    scramble[i] = permute(i, log2u(smax));
-  }
-}
-
-
-/* 
- * put keys in tabb according to key->b_k
- * check if the initial hash might work 
- */
-static int inittab(bstuff *tabb, ub4 blen, key *keys, ub4 nkeys, int complete)
-// bstuff   *tabb;                     /* output, list of keys with b for (a,b) */
-// ub4       blen;                                            /* length of tabb */
-// key      *keys;                               /* list of keys already hashed */
-// int       complete;        /* TRUE means to complete init despite collisions */
-{
-  int  nocollision = TRUE;
-  ub4 i;
-
-  memset((void *)tabb, 0, (size_t)(sizeof(bstuff)*blen));
-
-  /* Two keys with the same (a,b) guarantees a collision */
-  for (i = 0; i < nkeys; i++) {
-    key *mykey = keys+i;
-    key *otherkey;
-
-    for (otherkey=tabb[mykey->b_k].list_b; 
-	 otherkey; 
-	 otherkey=otherkey->nextb_k)
-    {
-      if (mykey->a_k == otherkey->a_k)
-      {
-        nocollision = FALSE;
-	if (!complete)
-	  return FALSE;
-      }
-    }
-    ++tabb[mykey->b_k].listlen_b;
-    mykey->nextb_k = tabb[mykey->b_k].list_b;
-    tabb[mykey->b_k].list_b = mykey;
-  }
-
-  /* no two keys have the same (a,b) pair */
-  return nocollision;
-}
-
-
-/* Do the initial hash for normal mode (use lookup and checksum) */
-static void initnorm(key *keys, ub4 nkeys, ub4 alen, ub4 blen, ub4 smax, ub8 salt)
-// key      *keys;                                          /* list of all keys */
-// ub4       alen;                    /* (a,b) has a in 0..alen-1, a power of 2 */
-// ub4       blen;                    /* (a,b) has b in 0..blen-1, a power of 2 */
-// ub4       smax;                   /* maximum range of computable hash values */
-// ub4       salt;                     /* used to initialize the hash function */
-// gencode  *final;                          /* output, code for the final hash */
-{
-  ub4 loga = log2u(alen);                            /* log based 2 of blen */
-  ub4 i;
-  for (i = 0; i < nkeys; i++) {
-    key *mykey = keys+i;
-    ub8 hash = lookup8(mykey->name_k, mykey->len_k, salt);
-    mykey->a_k = (loga > 0) ? hash>>(UB8BITS-loga) : 0;
-    mykey->b_k = (blen > 1) ? hash&(blen-1) : 0;
-  }
-}
-
-
-/* Try to apply an augmenting list */
-static int apply(bstuff *tabb, hstuff *tabh, qstuff *tabq, ub4 blen, ub4 *scramble, ub4 tail, int rollback)
-// bstuff *tabb;
-// hstuff *tabh;
-// qstuff *tabq;
-// ub4     blen;
-// ub4    *scramble;
-// ub4     tail;
-// int     rollback;          /* FALSE applies augmenting path, TRUE rolls back */
-{
-  ub4     hash;
-  key    *mykey;
-  bstuff *pb;
-  ub4     child;
-  ub4     parent;
-  ub4     stabb;                                         /* scramble[tab[b]] */
-
-  /* walk from child to parent */
-  for (child=tail-1; child; child=parent)
-  {
-    parent = tabq[child].parent_q;                    /* find child's parent */
-    pb     = tabq[parent].b_q;             /* find parent's list of siblings */
-
-    /* erase old hash values */
-    stabb = scramble[pb->val_b];
-    for (mykey=pb->list_b; mykey; mykey=mykey->nextb_k)
-    {
-      hash = mykey->a_k^stabb;
-      if (mykey == tabh[hash].key_h)
-      {                            /* erase hash for all of child's siblings */
-	tabh[hash].key_h = (key *)0;
-      }
-    }
-
-    /* change pb->val_b, which will change the hashes of all parent siblings */
-    pb->val_b = (rollback ? tabq[child].oldval_q : tabq[child].newval_q);
-
-    /* set new hash values */
-    stabb = scramble[pb->val_b];
-    for (mykey=pb->list_b; mykey; mykey=mykey->nextb_k)
-    {
-      hash = mykey->a_k^stabb;
-      if (rollback)
-      {
-	if (parent == 0) continue;                  /* root never had a hash */
-      }
-      else if (tabh[hash].key_h)
-      {
-	/* very rare: roll back any changes */
-        apply(tabb, tabh, tabq, blen, scramble, tail, TRUE);
-	return FALSE;                                  /* failure, collision */
-      }
-      tabh[hash].key_h = mykey;
-    }
-  }
-  return TRUE;
-}
-
-
-/*
--------------------------------------------------------------------------------
-augment(): Add item to the mapping.
-
-Construct a spanning tree of *b*s with *item* as root, where each
-parent can have all its hashes changed (by some new val_b) with 
-at most one collision, and each child is the b of that collision.
-
-I got this from Tarjan's "Data Structures and Network Algorithms".  The
-path from *item* to a *b* that can be remapped with no collision is 
-an "augmenting path".  Change values of tab[b] along the path so that 
-the unmapped key gets mapped and the unused hash value gets used.
-
-Assuming 1 key per b, if m out of n hash values are still unused, 
-you should expect the transitive closure to cover n/m nodes before 
-an unused node is found.  Sum(i=1..n)(n/i) is about nlogn, so expect
-this approach to take about nlogn time to map all single-key b's.
--------------------------------------------------------------------------------
-*/
-static int augment(bstuff *tabb, hstuff *tabh, qstuff *tabq, ub4 blen, ub4 *scramble, ub4 smax, bstuff *item, ub4 nkeys, 
-		   ub4 highwater)
-// bstuff   *tabb;                                        /* stuff indexed by b */
-// hstuff   *tabh;  /* which key is associated with which hash, indexed by hash */
-// qstuff   *tabq;            /* queue of *b* values, this is the spanning tree */
-// ub4       blen;                                            /* length of tabb */
-// ub4      *scramble;                      /* final hash is a^scramble[tab[b]] */
-// ub4       smax;                                 /* highest value in scramble */
-// bstuff   *item;                           /* &tabb[b] for the b to be mapped */
-// ub4       nkeys;                         /* final hash must be in 0..nkeys-1 */
-// ub4       highwater;        /* a value higher than any now in tabb[].water_b */
-{
-  ub4  q;                      /* current position walking through the queue */
-  ub4  tail;              /* tail of the queue.  0 is the head of the queue. */
-  ub4  limit=UB1MAXVAL+1;
-  ub4  highhash = smax;
-
-  /* initialize the root of the spanning tree */
-  tabq[0].b_q = item;
-  tail = 1;
-
-  /* construct the spanning tree by walking the queue, add children to tail */
-  for (q=0; q<tail; ++q)
-  {
-    bstuff *myb = tabq[q].b_q;                        /* the b for this node */
-    ub4     i;                              /* possible value for myb->val_b */
-
-    if (q == 1) 
-      break;                                  /* don't do transitive closure */
-
-    for (i=0; i<limit; ++i)
-    {
-      bstuff *childb = (bstuff *)0;             /* the b that this i maps to */
-      key    *mykey;                       /* for walking through myb's keys */
-
-      for (mykey = myb->list_b; mykey; mykey=mykey->nextb_k)
-      {
-	key    *childkey;
-	ub4 hash = mykey->a_k^scramble[i];
-
-	if (hash >= highhash) break;                        /* out of bounds */
-	childkey = tabh[hash].key_h;
-
-	if (childkey)
-	{
-	  bstuff *hitb = &tabb[childkey->b_k];
-
-	  if (childb)
-	  {
-	    if (childb != hitb) break;            /* hit at most one child b */
-	  }
-	  else
-	  {
-	    childb = hitb;                        /* remember this as childb */
-	    if (childb->water_b == highwater) break;     /* already explored */
-	  }
-	}
-      }
-      if (mykey) continue;             /* myb with i has multiple collisions */
-
-      /* add childb to the queue of reachable things */
-      if (childb) childb->water_b = highwater;
-      tabq[tail].b_q      = childb;
-      tabq[tail].newval_q = i;     /* how to make parent (myb) use this hash */
-      tabq[tail].oldval_q = myb->val_b;            /* need this for rollback */
-      tabq[tail].parent_q = q;
-      ++tail;
-
-      if (!childb)
-      {                                  /* found an *i* with no collisions? */
-	/* try to apply the augmenting path */
-	if (apply(tabb, tabh, tabq, blen, scramble, tail, FALSE))
-	  return TRUE;        /* success, item was added to the perfect hash */
-
-	--tail;                    /* don't know how to handle such a child! */
-      }
-    }
-  }
-  return FALSE;
-}
-
-
-/* find a mapping that makes this a perfect hash */
-static int perfect(bstuff *tabb, hstuff *tabh, qstuff *tabq, ub4 blen, ub4 smax, ub4 *scramble, ub4 nkeys)
-{
-  ub4 maxkeys;                           /* maximum number of keys for any b */
-  ub4 i, j;
-
-#if SELOPT_DEBUG
-  fprintf(stderr, "           blen %d smax %d nkeys %d\n", blen, smax, nkeys);
-#endif
-
-  /* clear any state from previous attempts */
-  memset((void *)tabh, 0, sizeof(hstuff)*smax);
-  memset((void *)tabq, 0, sizeof(qstuff)*(blen+1));
-
-  for (maxkeys=0,i=0; i<blen; ++i) 
-    if (tabb[i].listlen_b > maxkeys) 
-      maxkeys = tabb[i].listlen_b;
-
-  /* In descending order by number of keys, map all *b*s */
-  for (j=maxkeys; j>0; --j)
-    for (i=0; i<blen; ++i)
-      if (tabb[i].listlen_b == j)
-	if (!augment(tabb, tabh, tabq, blen, scramble, smax, &tabb[i], nkeys, 
-		     i+1))
-	{
-	  return FALSE;
-	}
-
-  /* Success!  We found a perfect hash of all keys into 0..nkeys-1. */
-  return TRUE;
-}
-
-
-/* guess initial values for alen and blen */
-static void initalen(ub4 *alen, ub4 *blen, ub4 smax, ub4 nkeys)
-// ub4      *alen;                                      /* output, initial alen */
-// ub4      *blen;                                      /* output, initial blen */
-// ub4      smax;    /* input, power of two greater or equal to max hash value */
-// ub4       nkeys;                              /* number of keys being hashed */
-{
-  /*
-   * Find initial *alen, *blen
-   * Initial alen and blen values were found empirically.  Some factors:
-   *
-   * If smax<256 there is no scramble, so tab[b] needs to cover 0..smax-1.
-   *
-   * alen and blen must be powers of 2 because the values in 0..alen-1 and
-   * 0..blen-1 are produced by applying a bitmask to the initial hash function.
-   *
-   * alen must be less than smax, in fact less than nkeys, because otherwise
-   * there would often be no i such that a^scramble[i] is in 0..nkeys-1 for
-   * all the *a*s associated with a given *b*, so there would be no legal
-   * value to assign to tab[b].  This only matters when we're doing a minimal
-   * perfect hash.
-   *
-   * It takes around 800 trials to find distinct (a,b) with nkey=smax*(5/8)
-   * and alen*blen = smax*smax/32.
-   *
-   * Values of blen less than smax/4 never work, and smax/2 always works.
-   *
-   * We want blen as small as possible because it is the number of bytes in
-   * the huge array we must create for the perfect hash.
-   *
-   * When nkey <= smax*(5/8), blen=smax/4 works much more often with 
-   * alen=smax/8 than with alen=smax/4.  Above smax*(5/8), blen=smax/4
-   * doesn't seem to care whether alen=smax/8 or alen=smax/4.  I think it
-   * has something to do with 5/8 = 1/8 * 5.  For example examine 80000, 
-   * 85000, and 90000 keys with different values of alen.  This only matters
-   * if we're doing a minimal perfect hash.
-   *
-   * When alen*blen <= 1<<UB4BITS, the initial hash must produce one integer.
-   * Bigger than that it must produce two integers, which increases the
-   * cost of the hash per character hashed.
-   */
-  *alen = smax;                     /* no reason to restrict alen to smax/2 */
-  *blen = ((nkeys <= smax*0.6) ? smax/16 : 
-           (nkeys <= smax*0.8) ? smax/8 : smax/4);
-  
-  if (*alen < 1) *alen = 1;
-  if (*blen < 1) *blen = 1;
-
-#if SELOPT_DEBUG
-  fprintf(stderr, "alen %d blen %d smax %d nkeys %d\n", *alen, *blen, smax, nkeys);
-#endif
-}
-
-/* 
-** Try to find a perfect hash function.  
-** Return the successful initializer for the initial hash. 
-** Return 0 if no perfect hash could be found.
-*/
-static int findhash(bstuff **tabb, ub4 *alen, ub4 *blen, ub8 *salt, 
-                    ub4 *scramble, ub4 smax, key *keys, ub4 nkeys)
-// bstuff  **tabb;           /* output, tab[] of the perfect hash, length *blen */
-// ub4      *alen;                 /* output, 0..alen-1 is range for a of (a,b) */
-// ub4      *blen;                 /* output, 0..blen-1 is range for b of (a,b) */
-// ub4      *salt;                         /* output, initializes initial hash */
-// ub4      *scramble;                      /* input, hash = a^scramble[tab[b]] */
-// ub4      smax;                           /* input, scramble[i] in 0..smax-1 */
-// key      *keys;                                       /* input, keys to hash */
-// ub4       nkeys;                       /* input, number of keys being hashed */
-{
-  ub4 bad_initkey;                       /* how many times did initkey fail? */
-  ub4 bad_perfect;                       /* how many times did perfect fail? */
-  ub4 si;                        /* trial initializer for initial hash */
-  ub4 maxalen;
-  hstuff *tabh;                       /* table of keys indexed by hash value */
-  qstuff *tabq;    /* table of stuff indexed by queue value, used by augment */
-
-  /* guess initial values for alen and blen */
-  initalen(alen, blen, smax, nkeys);
-
-  scrambleinit(scramble, smax);
-
-  maxalen = smax;
-
-  /* allocate working memory */
-  *tabb = new bstuff[*blen];
-  tabq  = new qstuff[*blen+1];
-  tabh  = new hstuff[smax];
-
-  /* Actually find the perfect hash */
-  *salt = 0;
-  bad_initkey = 0;
-  bad_perfect = 0;
-  for (si=1; ; ++si)
-  {
-    ub4 rslinit;
-    /* Try to find distinct (A,B) for all keys */
-    *salt = si * 0x9e3779b97f4a7c13LL; /* golden ratio (arbitrary value) */
-    initnorm(keys, nkeys, *alen, *blen, smax, *salt);
-    rslinit = inittab(*tabb, *blen, keys, nkeys, FALSE);
-    if (rslinit == 0)
-    {
-      /* didn't find distinct (a,b) */
-      if (++bad_initkey >= RETRY_INITKEY)
-      {
-	/* Try to put more bits in (A,B) to make distinct (A,B) more likely */
-	if (*alen < maxalen)
-	{
-	  *alen *= 2;
-	} 
-	else if (*blen < smax)
-	{
-	  *blen *= 2;
-	  delete[] tabq;
-	  delete[] *tabb;
-	  *tabb  = new bstuff[*blen];
-	  tabq  = new qstuff[*blen+1];
-	}
-	bad_initkey = 0;
-	bad_perfect = 0;
-      }
-      continue;                             /* two keys have same (a,b) pair */
-    }
-
-    /* Given distinct (A,B) for all keys, build a perfect hash */
-    if (!perfect(*tabb, tabh, tabq, *blen, smax, scramble, nkeys))
-    {
-      if (++bad_perfect >= RETRY_PERFECT)
-      {
-	if (*blen < smax)
-	{
-	  *blen *= 2;
-	  delete[] *tabb;
-	  delete[] tabq;
-	  *tabb  = new bstuff[*blen];
-	  tabq  = new qstuff[*blen+1];
-	  --si;               /* we know this salt got distinct (A,B) */
-	}
-	else
-	{
-          return 0;
-	}
-	bad_perfect = 0;
-      }
-      continue;
-    }
-    
-    break;
-  }
-
-  /* free working memory */
-  delete[] tabh;
-  delete[] tabq;
-
-  return 1;
-}
-
-/*
-------------------------------------------------------------------------------
-Input/output type routines
-------------------------------------------------------------------------------
-*/
-
-/* get the list of keys */
-static void getkeys(key **keys, ub4 *nkeys, const string_map& strings)
-{
-  key *buf = new key[strings.size()];
-  size_t i;
-  string_map::const_iterator s;
-  for (i = 0, s = strings.begin(); s != strings.end(); ++s, ++i) {
-    key *mykey = buf+i;
-    mykey->name_k = (ub1 *)s->first;
-    mykey->len_k  = (ub4)strlen(s->first);
-  }
-  *keys = buf;
-  *nkeys = strings.size();
-}
-
-
-static perfect_hash 
-make_perfect(const string_map& strings)
-{
-  ub4       nkeys;                                         /* number of keys */
-  key      *keys;                                    /* head of list of keys */
-  bstuff   *tab;                                       /* table indexed by b */
-  ub4       smax;            /* scramble[] values in 0..smax-1, a power of 2 */
-  ub4       alen;                            /* a in 0..alen-1, a power of 2 */
-  ub4       blen;                            /* b in 0..blen-1, a power of 2 */
-  ub8       salt;                       /* a parameter to the hash function */
-  ub4       scramble[SCRAMBLE_LEN];           /* used in final hash function */
-  int ok;
-  int i;
-  perfect_hash result;
-
-  /* read in the list of keywords */
-  getkeys(&keys, &nkeys, strings);
-
-  /* find the hash */
-  smax = ((ub4)1<<log2u(nkeys));
-  ok = findhash(&tab, &alen, &blen, &salt, 
-                scramble, smax, keys, nkeys);
-  if (!ok) {
-      smax = 2 * ((ub4)1<<log2u(nkeys));
-      ok = findhash(&tab, &alen, &blen, &salt, 
-                    scramble, smax, keys, nkeys);
-  }
-  if (!ok) {
-      bzero(&result, sizeof(result));
-  } else {
-      /* build the tables */
-      result.capacity = smax;
-      result.occupied = nkeys;
-      result.shift = UB8BITS - log2u(alen);
-      result.mask = blen - 1;
-      result.salt = salt;
-      
-      result.tab = new uint8_t[blen];
-      for (i = 0; i < blen; i++) {
-          result.tab[i] = tab[i].val_b;
-      }
-      for (i = 0; i < 256; i++) {
-          result.scramble[i] = scramble[i];
-      }
-  }
-
-  delete[] keys;
-  delete[] tab;
-
-  return result;
-}
-
-// SELOPT_WRITE
-#endif
-
-// namespace objc_selopt
-};
-
-#undef S32
-#undef S64
+} // namespace objc_opt
 
 #endif