From: Michael D. Lowis <mike.lowis@gentex.com>
Date: Wed, 23 Jun 2021 20:55:09 +0000 (-0400)
Subject: added very basic AST definition. Considering ditching ssa-like IR for simpler AST... 
X-Git-Url: https://git.mdlowis.com/?a=commitdiff_plain;h=5f9c93950538f6120eb6009c421fa6e18956f7ad;p=proto%2Fobnc.git

added very basic AST definition. Considering ditching ssa-like IR for simpler AST format
---

diff --git a/cerise/inc/cerise.h b/cerise/inc/cerise.h
index fa1345f..9b13ab8 100644
--- a/cerise/inc/cerise.h
+++ b/cerise/inc/cerise.h
@@ -55,6 +55,7 @@ typedef enum {
     VAR,
     WHILE,
     COUNT,
+    CALL,
     ERROR = -2,
     END_FILE = -1
 } TokType;
@@ -266,3 +267,84 @@ void ir_binopi(Parser* p, int op, long dest, long arg, long imm);
 void ir_binopf(Parser* p, int op, long dest, long arg, double imm);
 void ir_unnopi(Parser* p, int op, long dest, long imm);
 void ir_unopf(Parser* p, int op, long dest, double imm);
+
+
+
+/* Abstract Syntax Tree Definition
+ *****************************************************************************/
+struct AstNode;
+
+typedef struct {
+    int code : 28;
+    int mode : 4;
+    struct AstNode* next;
+    Type* type;
+} AstNodeHeader;
+
+typedef struct AstNode {
+    AstNodeHeader hdr;
+    struct AstNode* links[3];
+} AstNode;
+
+typedef struct {
+    AstNodeHeader hdr;
+    union {
+        long long i;
+        double f;
+        char* s;
+    } val;
+} AstValue;
+
+static AstNode* ast_new(int type, AstNode* l0, AstNode* l1, AstNode* l2)
+{
+    AstNode* node = calloc(1, sizeof(AstNode));
+    node->hdr.code = type;
+    node->links[0] = l0;
+    node->links[1] = l1;
+    node->links[2] = l2;
+    return node;
+}
+
+static AstNode* ast_int(long long val)
+{
+    AstValue* node = (AstValue*)ast_new(INT, NULL, NULL, NULL);
+    node->val.i = val;
+    return (AstNode*)node;
+}
+
+static AstNode* ast_real(double val)
+{
+    AstValue* node = (AstValue*)ast_new(REAL, NULL, NULL, NULL);
+    node->val.i = val;
+    return (AstNode*)node;
+}
+
+static AstNode* ast_binop(int op, AstNode* left, AstNode* right)
+{
+    return ast_new(op, left, right, NULL);
+}
+
+static AstNode* ast_unop(int op, AstNode* operand)
+{
+    return ast_new(op, operand, NULL, NULL);
+}
+
+static AstNode* ast_block(void)
+{
+    return ast_new(BEGIN, NULL, NULL, NULL);
+}
+
+static AstNode* ast_call(AstNode* func)
+{
+    return ast_new(CALL, func, NULL, NULL);
+}
+
+static AstNode* ast_if(AstNode* cond, AstNode* br1, AstNode* br2)
+{
+    return ast_new(IF, cond, br1, br2);
+}
+
+static AstNode* ast_return(AstNode* expr)
+{
+    return ast_new(RETURN, expr, NULL, NULL);
+}