Implement support for multiple PROC parameters.

dmsc · dmsc · commit a89cb1558942 · 2021-02-23T00:05:49.000-03:00
Parameters are pushed to the stack in the EXEC and popped in the PROC
start in the oposite order.

Implement a stack for storing the parameter variables, needed to reorder
parameters.
diff --git a/src/actions.asm b/src/actions.asm
@@ -31,7 +31,7 @@
         .exportzp       VT_WORD, VT_STRING, VT_FLOAT, VT_UNDEF
         .exportzp       VT_ARRAY_WORD, VT_ARRAY_BYTE, VT_ARRAY_STRING, VT_ARRAY_FLOAT
         .exportzp       LT_PROC_DATA, LT_PROC_2, LT_DO_LOOP, LT_REPEAT, LT_WHILE_1, LT_WHILE_2, LT_FOR_1, LT_FOR_2, LT_EXIT, LT_IF, LT_ELSE, LT_ELIF
-        .importzp       loop_sp, bpos, bptr, tmp1, tmp2, tmp3, opos
+        .importzp       var_sp, loop_sp, bpos, bptr, tmp1, tmp2, tmp3, opos
         .exportzp       reloc_addr
         ; From runtime.asm
         .import         read_word
@@ -104,9 +104,9 @@ read_fp = AFP
 
 ;----------------------------------------------------------
 ; Use cassette buffer for loop stack, max 128 bytes
-; Note that at $480 we store the interpreter stack.
 loop_stk        =       $400
-
+; And at $480 store the "variable" stack, used procedure parameters
+var_stk         =       $480
 
 ;----------------------------------------------------------
         .zeropage
@@ -627,27 +627,31 @@ do_create:
         ldx     label_count
         inc     label_count
 set_var:
-        stx     E_POP_VAR+1
+        stx     E_DO_EXEC+1
         clc
         rts
 .endproc
 
 .proc   E_DO_EXEC
-        ldx     E_POP_VAR+1
+        ldx     #0
         jsr     label_create::no_create
         jmp     E_LABEL::cloop
 .endproc
 
 ; PUSH/POP variables
 .proc   E_PUSH_VAR
         jsr     get_last_tok    ; Get variable ID from last token
-        sta     E_POP_VAR+1
+        ldx     var_sp
+        sta     var_stk, x
+        inc     var_sp
         clc
         rts
 .endproc
 
 .proc   E_POP_VAR
-        lda     #0
+        dec     var_sp
+        ldx     var_sp
+        lda     var_stk, x
         jmp     parser_emit_byte
 .endproc
 
diff --git a/src/basic.syn b/src/basic.syn
@@ -630,13 +630,17 @@ PAUSE_OPT:
         E_EOL emit { TOK_0 }
 
 # Optional expression for EXEC
-OPT_EXPR:
-        EXPR emit { TOK_PUSH }
+OPT_EXEC_PARAM:
+        EXPR EXEC_PARAM_MORE emit { TOK_PUSH }
+        pass
+
+EXEC_PARAM_MORE:
+        C_EXPR
         pass
 
 # Optional variable in PROC
 OPT_PROC_VAR:
-        VAR_WORD_SAVE emit { TOK_POP, TOK_VAR_STORE } E_POP_VAR
+        VAR_WORD_SAVE OPT_PROC_VAR emit { TOK_POP, TOK_VAR_STORE } E_POP_VAR
         pass
 
 # Parse a line
@@ -690,7 +694,7 @@ PARSE_LINE_COMMAND: statement
         "DEc" VAR_WORD_LVALUE_SADDR emit TOK_DEC
         "PRoc" emit { TOK_JUMP, LT_PROC_DATA } E_PUSH_LT E_LABEL_DEF emit LT_PROC_2 E_PUSH_LT OPT_PROC_VAR
         "ENDProc" E_POP_PROC_2 emit TOK_RET E_POP_PROC_DATA
-        "EXEc" E_LABEL_EXEC OPT_EXPR emit { TOK_CALL } E_DO_EXEC
+        "EXEc" E_LABEL_EXEC OPT_EXEC_PARAM emit { TOK_CALL } E_DO_EXEC
         "DAta" DATA_VAR DATA_END
         "END" emit TOK_END
 #@if FASTBASIC_FP
diff --git a/src/compiler/parser.cc b/src/compiler/parser.cc
@@ -255,20 +255,17 @@ bool SMB_E_PUSH_VAR(parse &s)
 {
     // nothing to do!
     s.debug("E_PUSH_VAR");
-    s.sto_var = s.remove_last().get_val();
+    s.var_stk.push_back(s.remove_last().get_val());
     return true;
 }
 
 bool SMB_E_POP_VAR(parse &s)
 {
     s.debug("E_POP_VAR");
-    if (s.sto_var < 0)
-    {
-        s.debug("---------->ERROR: no variable stored!\n");
-        return false;
-    }
-    s.emit_byte( s.sto_var );
-    s.sto_var = -1;
+    if (s.var_stk.empty())
+        throw parse_error("variable stack empty", s.pos);
+    s.emit_byte( s.var_stk.back() );
+    s.var_stk.pop_back();
     return true;
 }
 
diff --git a/src/compiler/parser.h b/src/compiler/parser.h
@@ -58,7 +58,7 @@ class parse {
                 int linenum;
         };
         std::string in_fname;
-        int sto_var;
+        std::vector<int> var_stk;
         int lvl, maxlvl;
         std::string str;
         size_t pos;
@@ -130,7 +130,6 @@ class parse {
         } expand;
 
         parse():
-            sto_var(-1),
             lvl(0), maxlvl(0), pos(0),
             max_pos(0), linenum(0), label_num(0),
             finalized(false),
@@ -211,7 +210,7 @@ class parse {
         void new_line(std::string l, int ln)
         {
             pos = max_pos = 0;
-            sto_var = -1;
+            var_stk.clear();
             str = l;
             saved_errors.clear();
             expand.text.clear();
diff --git a/src/parse.asm b/src/parse.asm
@@ -22,7 +22,7 @@
         .export         parser_start, parser_error, parser_skipws, parser_emit_byte, parser_inc_opos
         ; Parser state
         .exportzp       bptr, bpos, bmax, linenum, buf_ptr, end_ptr
-        .exportzp       loop_sp
+        .exportzp       loop_sp, var_sp
         ; Output state
         .exportzp       opos
         ; From actions.asm
@@ -34,7 +34,7 @@
         .import         alloc_prog
         .importzp       prog_ptr, BASIC_TOP
         ; From vars.asm
-        .importzp       var_count, label_count
+        .exportzp       var_count, label_count
         ; From runtime.asm
         .importzp       IOCHN, COLOR, IOERROR
         .import         putc
@@ -53,8 +53,15 @@ end_ptr:.res 2
 bmax:   .res 1
 opos:   .res 1
 pptr:   .res 2
-linenum:.res 2
-loop_sp:.res 1
+
+; This variables are cleared in one loop:
+zp_clear_start:
+linenum:        .res 2
+loop_sp:        .res 1
+var_sp:         .res 1
+label_count:    .res 1
+var_count:      .res 1
+zp_clear_end:
 
         .code
         .include "atari.inc"
@@ -177,11 +184,12 @@ parser_start:
         tsx
         stx     saved_cpu_stack
         lda     #0
-        sta     linenum
-        sta     linenum+1
-        sta     loop_sp
-        sta     var_count
-        sta     label_count
+        ldx     #zp_clear_end - zp_clear_start
+zp_clear:
+        sta     zp_clear_start, x
+        dex
+        bpl     zp_clear
+
 parse_line:
         ldx     #0
         stx     bpos
diff --git a/src/vars.asm b/src/vars.asm
@@ -20,10 +20,10 @@
 ; --------------------------------------------
 
         .export         var_search, list_search, name_new
-        .exportzp       var_namelen, label_count, var_count
+        .exportzp       var_namelen
 
         ; From alloc.asm
-        .importzp       var_buf, prog_ptr
+        .importzp       var_buf, prog_ptr, label_count, var_count
         .import         alloc_area_8
         ; From parser.asm
         .import         parser_skipws
@@ -44,8 +44,6 @@ INBUFF  = $F3
 name:   .res 2
 var:    .res 2
 len:    .res 1
-label_count:    .res 1
-var_count:      .res    1
 
 ; Use a longer name for external references
 var_namelen=    len
diff --git a/testsuite/tests/testproc.bas b/testsuite/tests/testproc.bas
@@ -20,9 +20,10 @@ endproc
 
 exec before
 
-exec param 123
+exec param 123, i * i * i
 
 ' Proc with a parameter
-proc param x
+proc param x y
    ? "X="; x
+   ? "Y="; y
 endproc
diff --git a/testsuite/tests/testproc.chk b/testsuite/tests/testproc.chk
@@ -14,3 +14,4 @@ Loop: 9
 Loop: 10
 -- test --
 X=123
+Y=1331

Original file line number	Diff line number	Diff line change
`@@ -255,20 +255,17 @@ bool SMB_E_PUSH_VAR(parse &s)`
`255`	`255`	`{`
`256`	`256`	`// nothing to do!`
`257`	`257`	`s.debug("E_PUSH_VAR");`
`258`		`- s.sto_var = s.remove_last().get_val();`
	`258`	`+ s.var_stk.push_back(s.remove_last().get_val());`
`259`	`259`	`return true;`
`260`	`260`	`}`
`261`	`261`
`262`	`262`	`bool SMB_E_POP_VAR(parse &s)`
`263`	`263`	`{`
`264`	`264`	`s.debug("E_POP_VAR");`
`265`		`- if (s.sto_var < 0)`
`266`		`- {`
`267`		`- s.debug("---------->ERROR: no variable stored!\n");`
`268`		`- return false;`
`269`		`- }`
`270`		`- s.emit_byte( s.sto_var );`
`271`		`- s.sto_var = -1;`
	`265`	`+ if (s.var_stk.empty())`
	`266`	`+ throw parse_error("variable stack empty", s.pos);`
	`267`	`+ s.emit_byte( s.var_stk.back() );`
	`268`	`+ s.var_stk.pop_back();`
`272`	`269`	`return true;`
`273`	`270`	`}`
`274`	`271`
-Original file line number
+Diff line change
 Loop: 10
 -- test --
 X=123
 +Y=1331