[hackers] [scc] [cc2] Fix wafting switches nodes || Roberto E. Vargas Caballero

From: <git_AT_suckless.org>
Date: Mon, 26 Sep 2016 12:00:42 +0200 (CEST)

commit e36b9e60ca5f6b0aaeca720137a70109f77025f5
Author: Roberto E. Vargas Caballero <roberto.vargas_AT_igrid-td.com>
AuthorDate: Mon Sep 26 11:33:40 2016 +0200
Commit: Roberto E. Vargas Caballero <roberto.vargas_AT_igrid-td.com>
CommitDate: Mon Sep 26 11:33:40 2016 +0200

    [cc2] Fix wafting switches nodes
    
    We need to have all the nodes related to a switch table
    together, because otherwise it is impossible to build
    a jump table. The code was wrong and it was generating
    corrupted statement lists.

diff --git a/cc2/parser.c b/cc2/parser.c
index e7f0112..496b900 100644
--- a/cc2/parser.c
+++ b/cc2/parser.c
_AT_@ -339,20 +339,36 @@ oreturn(char *token, union tokenop u)
         push(np);
 }
 
+/*
+ * Move np (which is a OCASE/ODEFAULT/OESWITCH) to be contigous with
+ * the last switch table. It is a bit ugly to touch directly curstmt
+ * here, but moving this function to node.c is worse, because we are
+ * putting knowledge of how the text is parsed into the node
+ * represtation module.
+ */
 static void
 waft(Node *np)
 {
- Node *p;
+ Node *lastcase, *next;;
         struct swtch *cur;
+ extern Node *curstmt;
 
         if (swp == swtbl)
                 error(EWTACKU);
 
         cur = swp - 1;
- p = cur->last;
- np->next = p->next;
- np->prev = p;
- p->next = np;
+ lastcase = cur->last;
+ next = lastcase->next;
+
+ np->next = next;
+ np->prev = lastcase;
+
+ if (next)
+ next->prev = np;
+ lastcase->next = np;
+
+ if (curstmt == cur->last)
+ curstmt = np;
         cur->last = np;
         cur->nr++;
 }
_AT_@ -361,13 +377,17 @@ static void
 bswitch(char *token, union tokenop u)
 {
         struct swtch *cur;
+ Node *np = newnode(u.op);
 
         if (swp == &swtbl[NR_BLOCK+1])
                 error(EWTACKO);
         cur = swp++;
         cur->nr = 0;
- jump(token, u);
- cur->first = cur->last = push(pop());
+
+ eval(strtok(NULL, "\t\n"));
+ np->left = pop();
+
+ push(cur->first = cur->last = np);
 }
 
 static void
_AT_@ -379,7 +399,7 @@ eswitch(char *token, union tokenop u)
                 error(EWTACKU);
         jump(token, u);
         waft(pop());
- cur = swp--;
+ cur = --swp;
         cur->first->u.i = cur->nr;
 }
 
Received on Mon Sep 26 2016 - 12:00:42 CEST