diff options
| -rw-r--r-- | sys/src/cmd/cc/com.c | 27 |
1 files changed, 17 insertions, 10 deletions
diff --git a/sys/src/cmd/cc/com.c b/sys/src/cmd/cc/com.c index b8a3b5c44..f67294510 100644 --- a/sys/src/cmd/cc/com.c +++ b/sys/src/cmd/cc/com.c @@ -1373,14 +1373,21 @@ compar(Node *n, int reverse) /* * Skip over left casts to find out the original expression range. */ - while(l->op == OCAST) + while(l->op == OCAST){ + lt = l->type; + rt = l->left->type; + if(lt == T || rt == T) + return 0; + if(lt->width < rt->width) + break; + if(lt->width == rt->width && ((lt->etype ^ rt->etype) & 1) != 0) + break; l = l->left; + } if(l->op == OCONST) return 0; lt = l->type; - if(lt == T) - return 0; - if(lt->etype == TXXX || lt->etype > TUVLONG) + if(lt == T || lt->etype == TXXX || lt->etype > TUVLONG) return 0; /* @@ -1399,16 +1406,17 @@ compar(Node *n, int reverse) if((rt->etype&1) && r->vconst < 0) /* signed negative */ x.a = ~0ULL; - if((lt->etype&1)==0){ + if(lt->etype & 1){ + /* signed */ + lo = big(~0ULL, -(1LL<<(lt->width*8-1))); + hi = big(0, (1LL<<(lt->width*8-1))-1); + } else { /* unsigned */ lo = big(0, 0); if(lt->width == 8) hi = big(0, ~0ULL); else - hi = big(0, (1LL<<(l->type->width*8))-1); - }else{ - lo = big(~0ULL, -(1LL<<(l->type->width*8-1))); - hi = big(0, (1LL<<(l->type->width*8-1))-1); + hi = big(0, (1LL<<(lt->width*8))-1); } switch(op){ @@ -1462,4 +1470,3 @@ if(debug['y']) prtree(n, "strange"); warn(n, "useless or misleading comparison: %s", cmpbuf); return 0; } - |