X-Git-Url: https://git.xonotic.org/?a=blobdiff_plain;f=ast.c;h=49446a111d7035085c90981018c91b02e48f5e06;hb=214c063b3f53430960c256372914f1b90d1457eb;hp=0d0776876665f36b5dffae1a6650e19dee34f2a3;hpb=4c9c6ee5bd39618bcaa5b99177622369dfddf992;p=xonotic%2Fgmqcc.git

diff --git a/ast.c b/ast.c
index 0d07768..49446a1 100644
--- a/ast.c
+++ b/ast.c
@@ -36,7 +36,7 @@
     ( (ast_node*)self )->node.destroy = (ast_node_delete*)destroyfn
 
 /* It must not be possible to get here. */
-static void _ast_node_destroy(ast_node *self)
+static GMQCC_NORETURN void _ast_node_destroy(ast_node *self)
 {
     fprintf(stderr, "ast node missing destroy()\n");
     abort();
@@ -238,8 +238,10 @@ ast_ifthen* ast_ifthen_new(lex_ctx ctx, ast_expression *cond, ast_expression *on
 void ast_ifthen_delete(ast_ifthen *self)
 {
     ast_unref(self->cond);
-    ast_unref(self->on_true);
-    ast_unref(self->on_false);
+    if (self->on_true)
+        ast_unref(self->on_true);
+    if (self->on_false)
+        ast_unref(self->on_false);
     ast_expression_delete((ast_expression*)self);
     mem_d(self);
 }
@@ -271,6 +273,41 @@ void ast_ternary_delete(ast_ternary *self)
     mem_d(self);
 }
 
+ast_loop* ast_loop_new(lex_ctx ctx,
+                       ast_expression *initexpr,
+                       ast_expression *precond,
+                       ast_expression *postcond,
+                       ast_expression *increment,
+                       ast_expression *body)
+{
+    ast_instantiate(ast_loop, ctx, ast_loop_delete);
+    ast_expression_init((ast_expression*)self, (ast_expression_codegen*)&ast_loop_codegen);
+
+    self->initexpr  = initexpr;
+    self->precond   = precond;
+    self->postcond  = postcond;
+    self->increment = increment;
+    self->body      = body;
+
+    return self;
+}
+
+void ast_loop_delete(ast_loop *self)
+{
+    if (self->initexpr)
+        ast_unref(self->initexpr);
+    if (self->precond)
+        ast_unref(self->precond);
+    if (self->postcond)
+        ast_unref(self->postcond);
+    if (self->increment)
+        ast_unref(self->increment);
+    if (self->body)
+        ast_unref(self->body);
+    ast_expression_delete((ast_expression*)self);
+    mem_d(self);
+}
+
 ast_store* ast_store_new(lex_ctx ctx, int op,
                          ast_value *dest, ast_expression *source)
 {
@@ -340,6 +377,9 @@ ast_function* ast_function_new(lex_ctx ctx, const char *name, ast_value *vtype)
     self->ir_func = NULL;
     self->curblock = NULL;
 
+    self->breakblock    = NULL;
+    self->continueblock = NULL;
+
     vtype->isconst = true;
     vtype->constval.vfunc = self;
 
@@ -368,10 +408,36 @@ void ast_function_delete(ast_function *self)
     mem_d(self);
 }
 
+static void ast_util_hexitoa(char *buf, size_t size, unsigned int num)
+{
+    unsigned int base = 10;
+#define checknul() do { if (size == 1) { *buf = 0; return; } } while (0)
+#define addch(x) do { *buf++ = (x); --size; checknul(); } while (0)
+    if (size < 1)
+        return;
+    checknul();
+    if (!num)
+        addch('0');
+    else {
+        while (num)
+        {
+            int digit = num % base;
+            num /= base;
+            addch('0' + digit);
+        }
+    }
+
+    *buf = 0;
+#undef addch
+#undef checknul
+}
+
 const char* ast_function_label(ast_function *self, const char *prefix)
 {
     size_t id = (self->labelcount++);
-    sprintf(self->labelbuf, "%16s%8u", prefix, (unsigned int)id);
+    size_t len = strlen(prefix);
+    strncpy(self->labelbuf, prefix, sizeof(self->labelbuf));
+    ast_util_hexitoa(self->labelbuf + len, sizeof(self->labelbuf)-len, id);
     return self->labelbuf;
 }
 
@@ -519,6 +585,19 @@ bool ast_function_codegen(ast_function *self, ir_builder *ir)
         if (!(*gen)((ast_expression*)self->blocks[i], self, false, &dummy))
             return false;
     }
+
+    /* TODO: check return types */
+    if (!self->curblock->is_return)
+    {
+        if (!self->vtype->expression.next ||
+            self->vtype->expression.next->expression.vtype == TYPE_VOID)
+            return ir_block_create_return(self->curblock, NULL);
+        else
+        {
+            /* error("missing return"); */
+            return false;
+        }
+    }
     return true;
 }
 
@@ -670,34 +749,60 @@ bool ast_ifthen_codegen(ast_ifthen *self, ast_function *func, bool lvalue, ir_va
     (void)out;
     (void)lvalue;
 
-    /* create blocks first, it's nicer if they're ordered */
+    /* generate the condition */
+    func->curblock = cond;
+    cgen = self->cond->expression.codegen;
+    if (!(*cgen)((ast_expression*)(self->cond), func, false, &condval))
+        return false;
+
+    /* on-true path */
 
     if (self->on_true) {
         /* create on-true block */
         ontrue = ir_function_create_block(func->ir_func, ast_function_label(func, "ontrue"));
         if (!ontrue)
             return false;
+
+        /* enter the block */
+        func->curblock = ontrue;
+
+        /* generate */
+        cgen = self->on_true->expression.codegen;
+        if (!(*cgen)((ast_expression*)(self->on_true), func, false, &dummy))
+            return false;
     } else
         ontrue = NULL;
-    
+
+    /* on-false path */
     if (self->on_false) {
         /* create on-false block */
         onfalse = ir_function_create_block(func->ir_func, ast_function_label(func, "onfalse"));
         if (!onfalse)
             return false;
+
+        /* enter the block */
+        func->curblock = onfalse;
+
+        /* generate */
+        cgen = self->on_false->expression.codegen;
+        if (!(*cgen)((ast_expression*)(self->on_false), func, false, &dummy))
+            return false;
     } else
         onfalse = NULL;
 
+    /* Merge block were they all merge in to */
     merge = ir_function_create_block(func->ir_func, ast_function_label(func, "endif"));
     if (!merge)
-        return NULL;
+        return false;
 
-    /* generate the condition */
-    func->curblock = cond;
-    cgen = self->cond->expression.codegen;
-    if (!(*cgen)((ast_expression*)(self->cond), func, false, &condval))
+    /* add jumps ot the merge block */
+    if (ontrue && !ir_block_create_jump(ontrue, merge))
+        return false;
+    if (onfalse && !ir_block_create_jump(onfalse, merge))
         return false;
 
+    /* we create the if here, that way all blocks are ordered :)
+     */
     if (!ir_block_create_if(cond, condval,
                             (ontrue  ? ontrue  : merge),
                             (onfalse ? onfalse : merge)))
@@ -705,36 +810,6 @@ bool ast_ifthen_codegen(ast_ifthen *self, ast_function *func, bool lvalue, ir_va
         return false;
     }
 
-    /* on-true path */
-    if (ontrue) {
-        /* enter the block */
-        func->curblock = ontrue;
-
-        /* generate */
-        cgen = self->on_true->expression.codegen;
-        if (!(*cgen)((ast_expression*)(self->on_true), func, false, &dummy))
-            return false;
-
-        /* jump to merge block */
-        if (!ir_block_create_jump(ontrue, merge))
-            return false;
-    }
-
-    /* on-false path */
-    if (onfalse) {
-        /* enter the block */
-        func->curblock = onfalse;
-
-        /* generate */
-        cgen = self->on_false->expression.codegen;
-        if (!(*cgen)((ast_expression*)(self->on_false), func, false, &dummy))
-            return false;
-
-        /* jump to merge block */
-        if (!ir_block_create_jump(ontrue, merge))
-            return false;
-    }
-
     /* Now enter the merge block */
     func->curblock = merge;
 
@@ -770,53 +845,54 @@ bool ast_ternary_codegen(ast_ternary *self, ast_function *func, bool lvalue, ir_
 
     /* In the following, contraty to ast_ifthen, we assume both paths exist. */
 
+    /* generate the condition */
+    func->curblock = cond;
+    cgen = self->cond->expression.codegen;
+    if (!(*cgen)((ast_expression*)(self->cond), func, false, &condval))
+        return false;
+
     /* create on-true block */
     ontrue = ir_function_create_block(func->ir_func, ast_function_label(func, "tern_T"));
     if (!ontrue)
         return false;
-    
+    else
+    {
+        /* enter the block */
+        func->curblock = ontrue;
+
+        /* generate */
+        cgen = self->on_true->expression.codegen;
+        if (!(*cgen)((ast_expression*)(self->on_true), func, false, &trueval))
+            return false;
+    }
+
     /* create on-false block */
     onfalse = ir_function_create_block(func->ir_func, ast_function_label(func, "tern_F"));
     if (!onfalse)
         return false;
+    else
+    {
+        /* enter the block */
+        func->curblock = onfalse;
 
+        /* generate */
+        cgen = self->on_false->expression.codegen;
+        if (!(*cgen)((ast_expression*)(self->on_false), func, false, &falseval))
+            return false;
+    }
+
+    /* create merge block */
     merge = ir_function_create_block(func->ir_func, ast_function_label(func, "tern_out"));
     if (!merge)
-        return NULL;
-
-    /* generate the condition */
-    func->curblock = cond;
-    cgen = self->cond->expression.codegen;
-    if (!(*cgen)((ast_expression*)(self->cond), func, false, &condval))
-        return false;
-
-    if (!ir_block_create_if(cond, condval, ontrue, onfalse))
         return false;
-
-    /* on-true path */
-    /* enter the block */
-    func->curblock = ontrue;
-
-    /* generate */
-    cgen = self->on_true->expression.codegen;
-    if (!(*cgen)((ast_expression*)(self->on_true), func, false, &trueval))
-        return false;
-
     /* jump to merge block */
     if (!ir_block_create_jump(ontrue, merge))
         return false;
-
-    /* on-false path */
-    /* enter the block */
-    func->curblock = onfalse;
-
-    /* generate */
-    cgen = self->on_false->expression.codegen;
-    if (!(*cgen)((ast_expression*)(self->on_false), func, false, &falseval))
+    if (!ir_block_create_jump(onfalse, merge))
         return false;
 
-    /* jump to merge block */
-    if (!ir_block_create_jump(ontrue, merge))
+    /* create if instruction */
+    if (!ir_block_create_if(cond, condval, ontrue, onfalse))
         return false;
 
     /* Now enter the merge block */
@@ -844,3 +920,231 @@ bool ast_ternary_codegen(ast_ternary *self, ast_function *func, bool lvalue, ir_
 
     return true;
 }
+
+bool ast_loop_codegen(ast_loop *self, ast_function *func, bool lvalue, ir_value **out)
+{
+    ast_expression_codegen *cgen;
+
+    ir_value *dummy      = NULL;
+    ir_value *precond    = NULL;
+    ir_value *postcond   = NULL;
+
+    /* Since we insert some jumps "late" so we have blocks
+     * ordered "nicely", we need to keep track of the actual end-blocks
+     * of expressions to add the jumps to.
+     */
+    ir_block *bbody      = NULL, *end_bbody      = NULL;
+    ir_block *bprecond   = NULL, *end_bprecond   = NULL;
+    ir_block *bpostcond  = NULL, *end_bpostcond  = NULL;
+    ir_block *bincrement = NULL, *end_bincrement = NULL;
+    ir_block *bout       = NULL, *bin            = NULL;
+
+    /* let's at least move the outgoing block to the end */
+    size_t    bout_id;
+
+    /* 'break' and 'continue' need to be able to find the right blocks */
+    ir_block *bcontinue     = NULL;
+    ir_block *bbreak        = NULL;
+
+    ir_block *old_bcontinue = NULL;
+    ir_block *old_bbreak    = NULL;
+
+    ir_block *tmpblock      = NULL;
+
+    (void)lvalue;
+    (void)out;
+
+    /* NOTE:
+     * Should we ever need some kind of block ordering, better make this function
+     * move blocks around than write a block ordering algorithm later... after all
+     * the ast and ir should work together, not against each other.
+     */
+
+    /* initexpr doesn't get its own block, it's pointless, it could create more blocks
+     * anyway if for example it contains a ternary.
+     */
+    if (self->initexpr)
+    {
+        cgen = self->initexpr->expression.codegen;
+        if (!(*cgen)((ast_expression*)(self->initexpr), func, false, &dummy))
+            return false;
+    }
+
+    /* Store the block from which we enter this chaos */
+    bin = func->curblock;
+
+    /* The pre-loop condition needs its own block since we
+     * need to be able to jump to the start of that expression.
+     */
+    if (self->precond)
+    {
+        bprecond = ir_function_create_block(func->ir_func, ast_function_label(func, "pre_loop_cond"));
+        if (!bprecond)
+            return false;
+
+        /* the pre-loop-condition the least important place to 'continue' at */
+        bcontinue = bprecond;
+
+        /* enter */
+        func->curblock = bprecond;
+
+        /* generate */
+        cgen = self->precond->expression.codegen;
+        if (!(*cgen)((ast_expression*)(self->precond), func, false, &precond))
+            return false;
+
+        end_bprecond = func->curblock;
+    } else {
+        bprecond = end_bprecond = NULL;
+    }
+
+    /* Now the next blocks won't be ordered nicely, but we need to
+     * generate them this early for 'break' and 'continue'.
+     */
+    if (self->increment) {
+        bincrement = ir_function_create_block(func->ir_func, ast_function_label(func, "loop_increment"));
+        if (!bincrement)
+            return false;
+        bcontinue = bincrement; /* increment comes before the pre-loop-condition */
+    } else {
+        bincrement = end_bincrement = NULL;
+    }
+
+    if (self->postcond) {
+        bpostcond = ir_function_create_block(func->ir_func, ast_function_label(func, "post_loop_cond"));
+        if (!bpostcond)
+            return false;
+        bcontinue = bpostcond; /* postcond comes before the increment */
+    } else {
+        bpostcond = end_bpostcond = NULL;
+    }
+
+    bout_id = func->ir_func->blocks_count;
+    bout = ir_function_create_block(func->ir_func, ast_function_label(func, "after_loop"));
+    if (!bout)
+        return false;
+    bbreak = bout;
+
+    /* The loop body... */
+    if (self->body)
+    {
+        bbody = ir_function_create_block(func->ir_func, ast_function_label(func, "loop_body"));
+        if (!bbody)
+            return false;
+
+        /* enter */
+        func->curblock = bbody;
+
+        old_bbreak          = func->breakblock;
+        old_bcontinue       = func->continueblock;
+        func->breakblock    = bbreak;
+        func->continueblock = bcontinue;
+
+        /* generate */
+        cgen = self->body->expression.codegen;
+        if (!(*cgen)((ast_expression*)(self->body), func, false, &dummy))
+            return false;
+
+        end_bbody = func->curblock;
+        func->breakblock    = old_bbreak;
+        func->continueblock = old_bcontinue;
+    }
+
+    /* post-loop-condition */
+    if (self->postcond)
+    {
+        /* enter */
+        func->curblock = bpostcond;
+
+        /* generate */
+        cgen = self->postcond->expression.codegen;
+        if (!(*cgen)((ast_expression*)(self->postcond), func, false, &postcond))
+            return false;
+
+        end_bpostcond = func->curblock;
+    }
+
+    /* The incrementor */
+    if (self->increment)
+    {
+        /* enter */
+        func->curblock = bincrement;
+
+        /* generate */
+        cgen = self->increment->expression.codegen;
+        if (!(*cgen)((ast_expression*)(self->increment), func, false, &dummy))
+            return false;
+
+        end_bincrement = func->curblock;
+    }
+
+    /* In any case now, we continue from the outgoing block */
+    func->curblock = bout;
+
+    /* Now all blocks are in place */
+    /* From 'bin' we jump to whatever comes first */
+    if      (bprecond)   tmpblock = bprecond;
+    else if (bbody)      tmpblock = bbody;
+    else if (bpostcond)  tmpblock = bpostcond;
+    else                 tmpblock = bout;
+    if (!ir_block_create_jump(bin, tmpblock))
+        return false;
+
+    /* From precond */
+    if (bprecond)
+    {
+        ir_block *ontrue, *onfalse;
+        if      (bbody)      ontrue = bbody;
+        else if (bincrement) ontrue = bincrement;
+        else if (bpostcond)  ontrue = bpostcond;
+        else                 ontrue = bprecond;
+        onfalse = bout;
+        if (!ir_block_create_if(end_bprecond, precond, ontrue, onfalse))
+            return false;
+    }
+
+    /* from body */
+    if (bbody)
+    {
+        if      (bincrement) tmpblock = bincrement;
+        else if (bpostcond)  tmpblock = bpostcond;
+        else if (bprecond)   tmpblock = bprecond;
+        else                 tmpblock = bout;
+        if (!ir_block_create_jump(end_bbody, tmpblock))
+            return false;
+    }
+
+    /* from increment */
+    if (bincrement)
+    {
+        if      (bpostcond)  tmpblock = bpostcond;
+        else if (bprecond)   tmpblock = bprecond;
+        else if (bbody)      tmpblock = bbody;
+        else                 tmpblock = bout;
+        if (!ir_block_create_jump(end_bincrement, tmpblock))
+            return false;
+    }
+
+    /* from postcond */
+    if (bpostcond)
+    {
+        ir_block *ontrue, *onfalse;
+        if      (bprecond)   ontrue = bprecond;
+        else if (bbody)      ontrue = bbody;
+        else if (bincrement) ontrue = bincrement;
+        else                 ontrue = bpostcond;
+        onfalse = bout;
+        if (!ir_block_create_if(end_bpostcond, postcond, ontrue, onfalse))
+            return false;
+    }
+
+    /* Move 'bout' to the end */
+    if (!ir_function_blocks_remove(func->ir_func, bout_id) ||
+        !ir_function_blocks_add(func->ir_func, bout))
+    {
+        ir_block_delete(bout);
+        return false;
+    }
+
+    return true;
+}