diff options
Diffstat (limited to 'src/cmd/5g/cgen.c')
| -rw-r--r-- | src/cmd/5g/cgen.c | 8 |
1 files changed, 8 insertions, 0 deletions
diff --git a/src/cmd/5g/cgen.c b/src/cmd/5g/cgen.c index 9faf75461..9011b2022 100644 --- a/src/cmd/5g/cgen.c +++ b/src/cmd/5g/cgen.c @@ -1490,6 +1490,7 @@ sgen(Node *n, Node *res, int64 w) } if(osrc%align != 0 || odst%align != 0) fatal("sgen: unaligned offset src %d or dst %d (align %d)", osrc, odst, align); + // if we are copying forward on the stack and // the src and dst overlap, then reverse direction dir = align; @@ -1674,6 +1675,13 @@ componentgen(Node *nr, Node *nl) freer = 1; } + // nl and nr are 'cadable' which basically means they are names (variables) now. + // If they are the same variable, don't generate any code, because the + // VARDEF we generate will mark the old value as dead incorrectly. + // (And also the assignments are useless.) + if(nr != N && nl->op == ONAME && nr->op == ONAME && nl == nr) + goto yes; + switch(nl->type->etype) { case TARRAY: if(nl->op == ONAME) |