duskos

commit c78f9c88cbc5a4bb51e6bc2f5d3c8e2f2b51d478
parent 6b3e0070bde0711ce26791070704d0392b323ede
Author: Virgil Dupras <hsoft@hardcoded.net>
Date:   Wed, 15 Jun 2022 16:34:22 -0400

cc: add "else" support in if statement

Diffstat:
M
fs/cc/ast.fs
 | 
6
++++--
M
fs/cc/gen.fs
 | 
5
++++-
M
fs/tests/cc/cc.fs
 | 
2
+-
M
fs/tests/cc/test.c
 | 
2
++

4 files changed, 11 insertions(+), 4 deletions(-)
diff --git a/fs/cc/ast.fs b/fs/cc/ast.fs
@@ -225,7 +225,6 @@ ASTIDCNT wordtbl astdatatbl ( node -- node )
     _nextt dup S" )" s= if 2drop exit then
     ',' expectChar _nextt again ;
 
-\ Parse a LValue
 \ Parse an assignment statement. It consists of a '=' char with an lvalue on
 \ the left and an expression on the right. The left part can have LValue ops
 \ applied to it.
@@ -248,7 +247,10 @@ create statementnames 6 c, ," return" 2 c, ," if" 0 c,
   _nextt '(' expectChar
   _nextt parseExpression ( sn ifn expr ) over addnode
   _nextt ')' expectChar
-  parseStatements ;
+  dup parseStatements ( snode ifnode )
+  _nextt dup S" else" s= if ( sn ifn tok )
+    drop parseStatements else
+    to nexttputback drop then ;
 
 : _ ( parentnode -- ) \ parseStatements
   _nextt '{' expectChar AST_STATEMENTS newnode _nextt
diff --git a/fs/cc/gen.fs b/fs/cc/gen.fs
@@ -99,7 +99,10 @@ ASTIDCNT wordtbl gentbl ( node -- )
 :w ( If )
   firstchild ?dup not if _err then dup gennode ( exprnode )
   operand?>result vmjz, swap ( jump_addr exprnode )
-  nextsibling ?dup not if _err then gennode ( jump_addr ) vmjmp! ;
+  nextsibling ?dup not if _err then dup gennode ( jump_addr condnode )
+  nextsibling ?dup if ( jump_addr elsenode )
+    vmjnz, ( ja1 enode ja2 ) rot vmjmp! ( enode ja2 )
+    swap gennode ( ja2 ) then ( jump_addr ) vmjmp! ;
 'w _err ( unused )
 :w ( FunCall )
   \ pass arguments
diff --git a/fs/tests/cc/cc.fs b/fs/tests/cc/cc.fs
@@ -15,6 +15,6 @@ funcall 42 #eq
 42 plusone 43 #eq
 ptrget 42 #eq
 ptrset 54 #eq
-12 condif 12 #eq
+12 condif 13 #eq
 42 condif 142 #eq
 testend
diff --git a/fs/tests/cc/test.c b/fs/tests/cc/test.c
@@ -40,6 +40,8 @@ int ptrset() {
 int condif(int x) {
     if (x == 42) {
         x = x+100;
+    } else {
+      x = x+1;
     }
     return x;
 }