]> git.xonotic.org Git - xonotic/gmqcc.git/blobdiff - ast.c
'likely' hint for IFs
[xonotic/gmqcc.git] / ast.c
diff --git a/ast.c b/ast.c
index 9e59ca917d73c9ed561b10f33bcf8087f01b3c28..f5ed565e93644b202798d2ff88c33ada85d57656 100644 (file)
--- a/ast.c
+++ b/ast.c
@@ -700,6 +700,49 @@ void ast_loop_delete(ast_loop *self)
     mem_d(self);
 }
 
+ast_breakcont* ast_breakcont_new(lex_ctx ctx, bool iscont)
+{
+    ast_instantiate(ast_breakcont, ctx, ast_breakcont_delete);
+    ast_expression_init((ast_expression*)self, (ast_expression_codegen*)&ast_breakcont_codegen);
+
+    self->is_continue = iscont;
+
+    return self;
+}
+
+void ast_breakcont_delete(ast_breakcont *self)
+{
+    ast_expression_delete((ast_expression*)self);
+    mem_d(self);
+}
+
+ast_switch* ast_switch_new(lex_ctx ctx, ast_expression *op)
+{
+    ast_instantiate(ast_switch, ctx, ast_switch_delete);
+    ast_expression_init((ast_expression*)self, (ast_expression_codegen*)&ast_switch_codegen);
+
+    self->operand = op;
+    self->cases   = NULL;
+
+    return self;
+}
+
+void ast_switch_delete(ast_switch *self)
+{
+    size_t i;
+    ast_unref(self->operand);
+
+    for (i = 0; i < vec_size(self->cases); ++i) {
+        if (self->cases[i].value)
+            ast_unref(self->cases[i].value);
+        ast_unref(self->cases[i].code);
+    }
+    vec_free(self->cases);
+
+    ast_expression_delete((ast_expression*)self);
+    mem_d(self);
+}
+
 ast_call* ast_call_new(lex_ctx ctx,
                        ast_expression *funcexpr)
 {
@@ -1345,6 +1388,10 @@ bool ast_block_codegen(ast_block *self, ast_function *func, bool lvalue, ir_valu
     for (i = 0; i < vec_size(self->exprs); ++i)
     {
         ast_expression_codegen *gen = self->exprs[i]->expression.codegen;
+        if (func->curblock->final) {
+            asterror(ast_ctx(self->exprs[i]), "unreachable statement");
+            return false;
+        }
         if (!(*gen)(self->exprs[i], func, false, out))
             return false;
     }
@@ -1466,13 +1513,60 @@ bool ast_binary_codegen(ast_binary *self, ast_function *func, bool lvalue, ir_va
         return true;
     }
 
+    if (OPTS_FLAG(SHORT_LOGIC) &&
+        (self->op == INSTR_AND || self->op == INSTR_OR))
+    {
+        /* short circuit evaluation */
+        ir_block *other, *merge;
+        ir_block *from_left, *from_right;
+        ir_instr *phi;
+        size_t    merge_id;
+
+        merge_id = vec_size(func->blocks);
+        merge = ir_function_create_block(func->ir_func, ast_function_label(func, "sce_merge"));
+
+        cgen = self->left->expression.codegen;
+        if (!(*cgen)((ast_expression*)(self->left), func, false, &left))
+            return false;
+
+        from_left = func->curblock;
+        other = ir_function_create_block(func->ir_func, ast_function_label(func, "sce_other"));
+        if (self->op == INSTR_AND) {
+            if (!ir_block_create_if(func->curblock, left, other, merge))
+                return false;
+        } else {
+            if (!ir_block_create_if(func->curblock, left, merge, other))
+                return false;
+        }
+        /* use the unlikely flag */
+        vec_last(func->curblock->instr)->likely = false;
+
+        func->curblock = other;
+        cgen = self->right->expression.codegen;
+        if (!(*cgen)((ast_expression*)(self->right), func, false, &right))
+            return false;
+        from_right = func->curblock;
+
+        if (!ir_block_create_jump(func->curblock, merge))
+            return false;
+
+        vec_remove(func->ir_func->blocks, merge_id, 1);
+        vec_push(func->ir_func->blocks, merge);
+
+        func->curblock = merge;
+        phi = ir_block_create_phi(func->curblock, ast_function_label(func, "sce_value"), TYPE_FLOAT);
+        ir_phi_add(phi, from_left, left);
+        ir_phi_add(phi, from_right, right);
+        *out = ir_phi_value(phi);
+        self->expression.outr = *out;
+        return true;
+    }
+
     cgen = self->left->expression.codegen;
-    /* lvalue! */
     if (!(*cgen)((ast_expression*)(self->left), func, false, &left))
         return false;
 
     cgen = self->right->expression.codegen;
-    /* rvalue! */
     if (!(*cgen)((ast_expression*)(self->right), func, false, &right))
         return false;
 
@@ -2184,6 +2278,185 @@ bool ast_loop_codegen(ast_loop *self, ast_function *func, bool lvalue, ir_value
     return true;
 }
 
+bool ast_breakcont_codegen(ast_breakcont *self, ast_function *func, bool lvalue, ir_value **out)
+{
+    ir_block *target;
+
+    if (lvalue) {
+        asterror(ast_ctx(self), "break/continue expression is not an l-value");
+        return false;
+    }
+
+    if (self->expression.outr) {
+        asterror(ast_ctx(self), "internal error: ast_breakcont cannot be reused!");
+        return false;
+    }
+    self->expression.outr = (ir_value*)1;
+
+    if (self->is_continue)
+        target = func->continueblock;
+    else
+        target = func->breakblock;
+
+    if (!ir_block_create_jump(func->curblock, target))
+        return false;
+    return true;
+}
+
+bool ast_switch_codegen(ast_switch *self, ast_function *func, bool lvalue, ir_value **out)
+{
+    ast_expression_codegen *cgen;
+
+    ast_switch_case *def_case  = NULL;
+    ir_block        *def_bfall = NULL;
+
+    ir_value *dummy     = NULL;
+    ir_value *irop      = NULL;
+    ir_block *old_break = NULL;
+    ir_block *bout      = NULL;
+    ir_block *bfall     = NULL;
+    size_t    bout_id;
+    size_t    c;
+
+    char      typestr[1024];
+    uint16_t  cmpinstr;
+
+    if (lvalue) {
+        asterror(ast_ctx(self), "switch expression is not an l-value");
+        return false;
+    }
+
+    if (self->expression.outr) {
+        asterror(ast_ctx(self), "internal error: ast_switch cannot be reused!");
+        return false;
+    }
+    self->expression.outr = (ir_value*)1;
+
+    (void)lvalue;
+    (void)out;
+
+    cgen = self->operand->expression.codegen;
+    if (!(*cgen)((ast_expression*)(self->operand), func, false, &irop))
+        return false;
+
+    if (!vec_size(self->cases))
+        return true;
+
+    cmpinstr = type_eq_instr[irop->vtype];
+    if (cmpinstr >= AINSTR_END) {
+        ast_type_to_string(self->operand, typestr, sizeof(typestr));
+        asterror(ast_ctx(self), "invalid type to perform a switch on: %s", typestr);
+        return false;
+    }
+
+    bout_id = vec_size(func->ir_func->blocks);
+    bout = ir_function_create_block(func->ir_func, ast_function_label(func, "after_switch"));
+    if (!bout)
+        return false;
+
+    /* setup the break block */
+    old_break        = func->breakblock;
+    func->breakblock = bout;
+
+    /* Now create all cases */
+    for (c = 0; c < vec_size(self->cases); ++c) {
+        ir_value *cond, *val;
+        ir_block *bcase, *bnot;
+        size_t bnot_id;
+
+        ast_switch_case *swcase = &self->cases[c];
+
+        if (swcase->value) {
+            /* A regular case */
+            /* generate the condition operand */
+            cgen = swcase->value->expression.codegen;
+            if (!(*cgen)((ast_expression*)(swcase->value), func, false, &val))
+                return false;
+            /* generate the condition */
+            cond = ir_block_create_binop(func->curblock, ast_function_label(func, "switch_eq"), cmpinstr, irop, val);
+            if (!cond)
+                return false;
+
+            bcase = ir_function_create_block(func->ir_func, ast_function_label(func, "case"));
+            bnot_id = vec_size(func->ir_func->blocks);
+            bnot = ir_function_create_block(func->ir_func, ast_function_label(func, "not_case"));
+            if (!bcase || !bnot)
+                return false;
+            if (!ir_block_create_if(func->curblock, cond, bcase, bnot))
+                return false;
+
+            /* Make the previous case-end fall through */
+            if (bfall && !bfall->final) {
+                if (!ir_block_create_jump(bfall, bcase))
+                    return false;
+            }
+
+            /* enter the case */
+            func->curblock = bcase;
+            cgen = swcase->code->expression.codegen;
+            if (!(*cgen)((ast_expression*)swcase->code, func, false, &dummy))
+                return false;
+
+            /* remember this block to fall through from */
+            bfall = func->curblock;
+
+            /* enter the else and move it down */
+            func->curblock = bnot;
+            vec_remove(func->ir_func->blocks, bnot_id, 1);
+            vec_push(func->ir_func->blocks, bnot);
+        } else {
+            /* The default case */
+            /* Remember where to fall through from: */
+            def_bfall = bfall;
+            bfall     = NULL;
+            /* remember which case it was */
+            def_case  = swcase;
+        }
+    }
+
+    /* Jump from the last bnot to bout */
+    if (bfall && !bfall->final && !ir_block_create_jump(bfall, bout)) {
+        /*
+        astwarning(ast_ctx(bfall), WARN_???, "missing break after last case");
+        */
+        return false;
+    }
+
+    /* If there was a default case, put it down here */
+    if (def_case) {
+        ir_block *bcase;
+
+        /* No need to create an extra block */
+        bcase = func->curblock;
+
+        /* Insert the fallthrough jump */
+        if (def_bfall && !def_bfall->final) {
+            if (!ir_block_create_jump(def_bfall, bcase))
+                return false;
+        }
+
+        /* Now generate the default code */
+        cgen = def_case->code->expression.codegen;
+        if (!(*cgen)((ast_expression*)def_case->code, func, false, &dummy))
+            return false;
+    }
+
+    /* Jump from the last bnot to bout */
+    if (!func->curblock->final && !ir_block_create_jump(func->curblock, bout))
+        return false;
+    /* enter the outgoing block */
+    func->curblock = bout;
+
+    /* restore the break block */
+    func->breakblock = old_break;
+
+    /* Move 'bout' to the end, it's nicer */
+    vec_remove(func->ir_func->blocks, bout_id, 1);
+    vec_push(func->ir_func->blocks, bout);
+
+    return true;
+}
+
 bool ast_call_codegen(ast_call *self, ast_function *func, bool lvalue, ir_value **out)
 {
     ast_expression_codegen *cgen;