From 1b9fe3b44a5d532a2c21bdf0c83196f7b92f80ba Mon Sep 17 00:00:00 2001
From: Zander Thannhauser <zthannhauser@gmail.com>
Date: Fri, 27 Jun 2025 14:54:26 -0500
Subject: [PATCH] .

---
 calculate_simplifications.c  | 488 +++++++++++++++--------------------
 debug.h                      |  15 +-
 get_cached_simplifications.c |  42 ++-
 get_cached_simplifications.h |   2 +-
 main.c                       |   2 +
 makefile                     |   2 +-
 simplifications.h            |   4 +-
 7 files changed, 259 insertions(+), 296 deletions(-)

diff --git a/calculate_simplifications.c b/calculate_simplifications.c
index 6e780b0..b0b86c6 100644
--- a/calculate_simplifications.c
+++ b/calculate_simplifications.c
@@ -11,120 +11,112 @@
 
 #include "calculate_simplifications.h"
 
-
-static void init_simplifications(
-    struct simplifications* simps)
+struct simplifications calculate_simplifications(
+    const struct cmdln_flags* flags)
 {
-    for (int i = 0; i < N; i++)
+    struct simplifications simps = {};
+    
+    // init 'simps.data':
     {
-        simps->data[i].kind = ek_unreachable;
+        for (int i = 0; i < N; i++)
+        {
+            simps.data[i].kind = ek_unreachable;
+            
+            simps.data[i].cost = INT_MAX;
+        }
+    }
+    
+    // heap of truthtables; key = cost
+    struct {
+        uint16_t data[N];
+        int n;
         
-        simps->data[i].cost = INT_MAX;
-    }
-}
-
-struct heap
-{
-    uint16_t data[N];
-    int n;
+        // truthtable -> index in 'todo'
+        int reverse[N];
+    } todo;
     
-    // truthtable -> index in 'todo'
-    int reverse[N];
-};
-
-static struct heap new_heap(void)
-{
-    zprintf("new_heap" "\n");
-    
-    struct heap todo = {};
-    
-    todo.n = 0;
-    
-    for (int i = 0; i < N; i++)
+    // init 'todo':
     {
-        todo.reverse[i] = -1;
-    }
-    
-    return todo;
-}
-
-
-uint16_t heap_pop(struct heap* todo, struct simplifications *simps)
-{
-    assert(todo->n > 0);
-
-    uint16_t retval = todo->data[0];
-
-    todo->reverse[retval] = -1;
-
-    uint16_t moving = todo->data[todo->n-- - 1];
-
-    int cost = simps->data[moving].cost;
-
-    int index = 0;
-
-    again:
-    {
-        int left = index * 2 + 1;
-        int right = index * 2 + 2;
-
-        uint16_t smallest = moving;
-
-        if (left < todo->n && simps->data[todo->data[left]].cost < cost)
-            smallest = todo->data[left];
-
-        if (right < todo->n && simps->data[todo->data[right]].cost < simps->data[smallest].cost)
-            smallest = todo->data[right];
-
-        if (smallest == moving)
+        todo.n = 0;
+        
+        for (int i = 0; i < N; i++)
         {
-            todo->data[index] = moving;
-
-            todo->reverse[moving] = index;
-        }
-        else
-        {
-            int new = todo->reverse[smallest];
-
-            todo->data[index] = smallest;
-
-            todo->reverse[smallest] = index;
-
-            index = new;
-
-            goto again;
+            todo.reverse[i] = -1;
         }
     }
-
-    return retval;
-}
-
-
-void heap_append(struct heap* todo, struct simplifications* simps, uint16_t truthtable, int cost)
-{
-    zprintf("heap_append()" "\n");
     
-    assert(todo->reverse[truthtable] == -1);
-
-    int index = todo->n++, new_index;
-
-    while (index > 0 && simps->data[todo->data[new_index = (index - 1) / 2]].cost > cost)
+    uint16_t pop(void)
     {
-        todo->data[index] = todo->data[new_index];
+        assert(todo.n > 0);
 
-        todo->reverse[todo->data[new_index]] = index;
+        uint16_t retval = todo.data[0];
 
-        index = new_index;
+        todo.reverse[retval] = -1;
+
+        uint16_t moving = todo.data[todo.n-- - 1];
+
+        int cost = simps.data[moving].cost;
+
+        int index = 0;
+
+        again:
+        {
+            int left = index * 2 + 1;
+            int right = index * 2 + 2;
+
+            uint16_t smallest = moving;
+
+            if (left < todo.n && simps.data[todo.data[left]].cost < cost)
+                smallest = todo.data[left];
+
+            if (right < todo.n && simps.data[todo.data[right]].cost < simps.data[smallest].cost)
+                smallest = todo.data[right];
+
+            if (smallest == moving)
+            {
+                todo.data[index] = moving;
+
+                todo.reverse[moving] = index;
+            }
+            else
+            {
+                int new = todo.reverse[smallest];
+
+                todo.data[index] = smallest;
+
+                todo.reverse[smallest] = index;
+
+                index = new;
+
+                goto again;
+            }
+        }
+
+        return retval;
+    }
+
+    void append(uint16_t truthtable, int cost)
+    {
+        assert(todo.reverse[truthtable] == -1);
+
+        int index = todo.n++, new_index;
+
+        while (index > 0 && simps.data[todo.data[new_index = (index - 1) / 2]].cost > cost)
+        {
+            todo.data[index] = todo.data[new_index];
+
+            todo.reverse[todo.data[new_index]] = index;
+
+            index = new_index;
+        }
+        
+        todo.data[index] = truthtable;
+        
+        todo.reverse[truthtable] = index;
+        
+        simps.data[truthtable].cost = cost;
     }
-    
-    todo->data[index] = truthtable;
-    
-    todo->reverse[truthtable] = index;
-    
-    simps->data[truthtable].cost = cost;
-}
 
-#if 0
     void update(uint16_t truthtable, int cost)
     {
         assert(todo.reverse[truthtable] != -1);
@@ -147,147 +139,134 @@ void heap_append(struct heap* todo, struct simplifications* simps, uint16_t trut
 
         simps.data[truthtable].cost = cost;
     }
-#endif
-
- // create a list of the "done" truthtables
-struct sparselist
-{
-    int headtails[N], next[N], head;
     
-    // for debugging:
-    #if ZDEBUG
-    bool in[N];
-    #endif
-};
-
-struct sparselist new_sparselist(void)
-{
-    struct sparselist done = {};
+    // create a list of the "done" truthtables
+    struct {
+        int headtails[N], next[N], head;
+        
+        // for debugging:
+        #if ZDEBUG
+        bool in[N];
+        #endif
+    } done = {};
     
-    done.head = -1;
-    
-    for (int i = 0; i < N; i++)
+    // init 'done':
     {
-        done.headtails[i] = -1;
+        done.head = -1;
+        
+        for (int i = 0; i < N; i++)
+        {
+            done.headtails[i] = -1;
+            
+            #if ZDEBUG
+            done.in[i] = false;
+            #endif
+        }
+    }
+    
+    void insert(int index)
+    {
+        #if ZDEBUG
+        assert(!done.in[index]);
+        #endif
+        
+        int head = index & 1 ? index & ~(index & -index) : index, prevhead = -1;
+        
+        while (done.headtails[head] == -1 || index < done.headtails[head])
+        {
+            done.headtails[head] = index;
+            
+            prevhead = head, head = head & ~(head & -head);
+        }
+        
+        if (done.headtails[head] < index)
+        {
+            if (prevhead == -1)
+            {
+                assert(done.headtails[head] == head);
+                
+                done.next[head] = index;
+            }
+            else
+            {
+                int tophalftail = done.headtails[prevhead - 1];
+                
+                assert(tophalftail != -1);
+                
+                done.next[tophalftail] = index;
+            }
+        }
+        else
+        {
+            done.head = index;
+        }
+        
+        int n = ~index & M;
+        int tail = index & 1 ? index : index | (n & -n), prevtail = -1;
+        
+        while (done.headtails[tail] == -1 || done.headtails[tail] < index)
+        {
+            done.headtails[tail] = index;
+            
+            prevtail = tail, tail = tail | (n = ~tail & M, n & -n);
+        }
+        
+        if (index < done.headtails[tail])
+        {
+            if (prevtail == -1)
+            {
+                assert(done.headtails[tail] == tail);
+                
+                #if ZDEBUG
+                assert(done.in[tail]);
+                #endif
+                
+                done.next[index] = tail;
+            }
+            else
+            {
+                int bottomhalfhead = done.headtails[prevtail + 1];
+                
+                assert(bottomhalfhead != -1);
+                
+                done.next[index] = bottomhalfhead;
+            }
+        }
+        else
+        {
+            done.next[index] = -1;
+        }
         
         #if ZDEBUG
-        done.in[i] = false;
+        done.in[index] = true;
         #endif
     }
     
-    return done;
-}
-
-void sparselist_insert(struct sparselist* this, int index)
-{
-    TODO;
-    #if 0
-    #if ZDEBUG
-    assert(!done.in[index]);
-    #endif
+    append(W, 0), simps.data[W].kind = ek_W;
+    append(X, 0), simps.data[X].kind = ek_X;
+    append(Y, 0), simps.data[Y].kind = ek_Y;
+    append(Z, 0), simps.data[Z].kind = ek_Z;
     
-    int head = index & 1 ? index & ~(index & -index) : index, prevhead = -1;
-    
-    while (done.headtails[head] == -1 || index < done.headtails[head])
-    {
-        done.headtails[head] = index;
-        
-        prevhead = head, head = head & ~(head & -head);
-    }
-    
-    if (done.headtails[head] < index)
-    {
-        if (prevhead == -1)
-        {
-            assert(done.headtails[head] == head);
-            
-            done.next[head] = index;
-        }
-        else
-        {
-            int tophalftail = done.headtails[prevhead - 1];
-            
-            assert(tophalftail != -1);
-            
-            done.next[tophalftail] = index;
-        }
-    }
-    else
-    {
-        done.head = index;
-    }
-    
-    int n = ~index & M;
-    int tail = index & 1 ? index : index | (n & -n), prevtail = -1;
-    
-    while (done.headtails[tail] == -1 || done.headtails[tail] < index)
-    {
-        done.headtails[tail] = index;
-        
-        prevtail = tail, tail = tail | (n = ~tail & M, n & -n);
-    }
-    
-    if (index < done.headtails[tail])
-    {
-        if (prevtail == -1)
-        {
-            assert(done.headtails[tail] == tail);
-            
-            #if ZDEBUG
-            assert(done.in[tail]);
-            #endif
-            
-            done.next[index] = tail;
-        }
-        else
-        {
-            int bottomhalfhead = done.headtails[prevtail + 1];
-            
-            assert(bottomhalfhead != -1);
-            
-            done.next[index] = bottomhalfhead;
-        }
-    }
-    else
-    {
-        done.next[index] = -1;
-    }
-    
-    #if ZDEBUG
-    done.in[index] = true;
-    #endif
-    #endif
-}
-
-
-static void loop(
-    const struct cmdln_flags* flags,
-    struct simplifications* simps,
-    struct heap* todo,
-    struct sparselist* done)
-{
-    zprintf("loop()" "\n");
+    append(0, 1), simps.data[0].kind = ek_0;
+    append(M, 1), simps.data[M].kind = ek_1;
     
     // disable terminal autowrap:
-    if (!ZDEBUG && flags->verbose && flags->print_with_color)
+    if (flags->verbose && flags->print_with_color)
     {
         printf("\e[?7l");
     }
 
-    for (int iterations = 1; todo->n && iterations <= N; iterations++)
+    for (int iterations = 1; todo.n && iterations <= N; iterations++)
     {
-        uint16_t truthtable = heap_pop(todo, simps);
+        uint16_t truthtable = pop();
         
-        if (!done)
-        {
-            sparselist_insert(done, truthtable);
-        }
+        insert(truthtable);
         
-        int cost = simps->data[truthtable].cost;
+        int cost = simps.data[truthtable].cost;
 
         if (flags->verbose)
         {
-            if (!ZDEBUG && flags->print_with_color)
+            if (flags->print_with_color)
             {
                 printf("\e[2K");
             }
@@ -295,16 +274,14 @@ static void loop(
             printf("%i of %i (%.2f%%): [%i] ",
                 iterations, N, (100.0 * iterations / N), cost);
 
-            print(flags, &simps->data, truthtable), puts("");
+            print(flags, &simps, truthtable), puts("");
 
-            if (!ZDEBUG && flags->print_with_color)
+            if (flags->print_with_color)
             {
                 printf("\e[1A");
             }
         }
 
-        TODO
-        #if 0
         // consider NOT:
         if (flags->use_operators.not)
         {
@@ -482,72 +459,17 @@ static void loop(
                 }
             }
         }
-        #endif
     }
 
     // clear progress line, enable terminal autowrap:
-    if (!ZDEBUG && flags->verbose && flags->print_with_color)
+    if (flags->verbose && flags->print_with_color)
     {
         printf("\e[2K"), printf("\e[?7h");
     }
+    
+    return simps;
 }
 
-struct simplifications calculate_simplifications(
-    const struct cmdln_flags* flags)
-{
-    zprintf("calculate_simplifications()" "\n");
-    
-    struct simplifications simps = {};
-    
-    init_simplifications(&simps);
-    
-    struct heap todo = new_heap();
-    
-    struct sparselist done = new_sparselist();
-    
-    heap_append(&todo, &simps, W, 0), simps.data[W].kind = ek_W;
-    heap_append(&todo, &simps, X, 0), simps.data[X].kind = ek_X;
-    heap_append(&todo, &simps, Y, 0), simps.data[Y].kind = ek_Y;
-    heap_append(&todo, &simps, Z, 0), simps.data[Z].kind = ek_Z;
-    
-    heap_append(&todo, &simps, 0, 1), simps.data[0].kind = ek_0;
-    heap_append(&todo, &simps, M, 1), simps.data[M].kind = ek_1;
-    
-    loop(flags, &simps, &todo, &done);
-    
-    TODO;
-}
-
-struct simplifications calculate_simplifications_with_extra_variable(
-    const struct cmdln_flags* flags,
-    uint16_t A)
-{
-    zprintf("calculate_simplifications_with_extra_variable()" "\n");
-    
-    #if 0
-    
-    if (have_extra_variable && todo.reverse[A] == -1)
-    {
-        append(A, 0), simps.data[A].kind = ek_A;
-    }
-    
-    #endif
-    
-    TODO;
-}
-
-void update_simplifications(
-    struct simplifications* simps,
-    const struct cmdln_flags* flags,
-    uint16_t starting_with)
-{
-    zprintf("update_simplifications()" "\n");
-    
-    TODO;
-}
-
-#if 0
-    
 
 
 
@@ -562,5 +484,3 @@ void update_simplifications(
 
 
 
-
-#endif
diff --git a/debug.h b/debug.h
index e1e92fc..dd62324 100644
--- a/debug.h
+++ b/debug.h
@@ -1,15 +1,20 @@
 
-#ifndef ZDEBUG
-    #define ZDEBUG 1
+#ifdef DEBUG_BUILD
+extern int debug_depth;
 #endif
 
-#if ZDEBUG
-    #define zprintf(fmt, ...) \
-        printf(fmt, ## __VA_ARGS__);
+#ifdef DEBUG_BUILD
+    #define zprintf(fmt, ...) printf("%*s" fmt, debug_depth, "", ## __VA_ARGS__);
 #else
     #define zprintf(...);
 #endif
 
+#define ENTER \
+    { zprintf("%s():" "\n", __PRETTY_FUNCTION__); debug_depth++; }
+
+#define EXIT \
+    { zprintf("return" "\n");  debug_depth--; }
+
 #define TODO \
     assert(!"TODO");
 
diff --git a/get_cached_simplifications.c b/get_cached_simplifications.c
index 266fc7f..1f0c998 100644
--- a/get_cached_simplifications.c
+++ b/get_cached_simplifications.c
@@ -83,16 +83,20 @@ static struct path { char data[PATH_MAX]; } get_path(
     return path;
 }
 
-void get_cached_simplifications(const struct cmdln_flags* flags)
+struct simplifications* get_cached_simplifications(const struct cmdln_flags* flags)
 {
-    zprintf("get_cached_simplifications()" "\n");
+    ENTER;
     
     struct path path = get_path(flags);
     
+    zprintf("path.data = %s\n", path.data);
+    
     int fd = -1;
     
     bool rebuild = flags->force_rebuild;
     
+    struct simplifications* simps;
+    
     if (!rebuild)
     {
         fd = open(path.data, O_RDONLY);
@@ -131,6 +135,7 @@ void get_cached_simplifications(const struct cmdln_flags* flags)
     
     if (rebuild)
     {
+        #ifndef DEBUG_BUILD
         if (!flags->quiet)
         {
             puts(""
@@ -152,8 +157,9 @@ void get_cached_simplifications(const struct cmdln_flags* flags)
             puts("Any input to start:"), getchar();
             puts("Started.");
         }
+        #endif
 
-        fd = open("/tmp/", O_RDWR | O_TMPFILE, 0664);
+        fd = open(".simplifier-cache-temp.bin", O_TRUNC | O_CREAT | O_RDWR, 0664);
     
         if (fd < 0)
         {
@@ -161,8 +167,30 @@ void get_cached_simplifications(const struct cmdln_flags* flags)
             exit(1);
         }
         
-        struct simplifications simps = calculate_simplifications(flags);
+        if (ftruncate(fd, sizeof(*simps)) < 0)
+        {
+            TODO;
+        }
         
+        void* ptr = mmap(
+            /* addr: */ NULL,
+            /* len: */ sizeof(*simps),
+            /* prot: */ PROT_WRITE | PROT_READ,
+            /* flags: */ MAP_PRIVATE,
+            /* fd: */ fd,
+            /* offset: */ 0);
+
+        if (ptr == MAP_FAILED)
+        {
+            TODO;
+        }
+        
+        simps = ptr;
+        
+        simps->initial = calculate_simplifications(flags);
+        
+        TODO;
+        #if 0
         TODO;
         #if 0
         if (flags->use_operators.assignment)
@@ -228,8 +256,11 @@ void get_cached_simplifications(const struct cmdln_flags* flags)
         
         }
         #endif
+        #endif
     }
 
+    TODO;
+    #if 0
     TODO;
     #if 0
     assert(fd > 0);
@@ -238,6 +269,9 @@ void get_cached_simplifications(const struct cmdln_flags* flags)
     
     return retval;
     #endif
+    #endif
+    
+    return simps;
 }
 
 
diff --git a/get_cached_simplifications.h b/get_cached_simplifications.h
index b55b084..6922f39 100644
--- a/get_cached_simplifications.h
+++ b/get_cached_simplifications.h
@@ -3,5 +3,5 @@
 
 struct cmdln_flags;
 
-void get_cached_simplifications(const struct cmdln_flags* flags);
+struct simplifications* get_cached_simplifications(const struct cmdln_flags* flags);
 
diff --git a/main.c b/main.c
index b11c766..57e24ba 100644
--- a/main.c
+++ b/main.c
@@ -19,6 +19,8 @@
 
 int main(int argc, char* const* argv)
 {
+    ENTER;
+    
     struct cmdln_flags flags = parse_args(argc, argv);
 
     get_cached_simplifications(&flags);
diff --git a/makefile b/makefile
index 2e98edc..192ebb5 100644
--- a/makefile
+++ b/makefile
@@ -14,7 +14,7 @@ default: ${prefix}/bsimp
 %/:
 	@mkdir -p $@
 
-srcs += calculate_simplifications.c cmdln.c evaluate.c
+srcs += calculate_simplifications.c cmdln.c evaluate.c debug.c
 srcs += get_cached_simplifications.c main.c print.c
 
 ${prefix}/%.o ${prefix}/%.d: %.c ${optionset} | ${prefix}/%/
diff --git a/simplifications.h b/simplifications.h
index 73cd07d..4f9739b 100644
--- a/simplifications.h
+++ b/simplifications.h
@@ -8,7 +8,9 @@
 
 struct simplifications
 {
-    struct expr data[N];
+    struct row {
+        struct expr data[N];
+    } initial, with_variables[N];
 };
 
 #endif