| Summary: | memmove doesn't work with tagged address | ||
|---|---|---|---|
| Product: | glibc | Reporter: | H.J. Lu <hjl.tools> |
| Component: | string | Assignee: | Not yet assigned to anyone <unassigned> |
| Status: | RESOLVED OBSOLETE | ||
| Severity: | normal | CC: | carlos, fweimer |
| Priority: | P2 | ||
| Version: | 2.34 | ||
| Target Milestone: | --- | ||
| Host: | Target: | ||
| Build: | Last reconfirmed: | ||
Overlapping pointers should have the same tag. |
string/memmove.c has rettype inhibit_loop_to_libcall MEMMOVE (a1const void *a1, a2const void *a2, size_t len) { unsigned long int dstp = (long int) dest; unsigned long int srcp = (long int) src; /* This test makes the forward copying code be used whenever possible. Reduces the working set. */ if (dstp - srcp >= len) /* *Unsigned* compare! */ ^^^^^^^^^^^^ This doesn't work with tagged address. { ... } Processor specific memmove may have the same issue. sysdeps/x86_64/multiarch/memmove-vec-unaligned-erms.S: 247 L(start_movsb): 248 mov %RDX_LP, %RCX_LP 249 cmp %RSI_LP, %RDI_LP ^^^^^^^^^^^^^^^^^^^^^^^^ This has the same issue. 250 jb 1f