| Commit message (Expand) | Author | Files | Lines |
|---|
| 2018-10-18 | fix wrong result for putc variants due to operator precedence•••the internal putc_unlocked macro was wrongly returning a meaningless
boolean result rather than the written character or EOF.
bug was found by reading (very surprising) asm.
| Rich Felker | 1 | -1/+1 |
| 2018-10-18 | further optimize getc/putc when locking is needed•••check whether the lock is free before loading the calling thread's
tid. if so, just use a dummy tid value that cannot compare equal to
any actual thread id (because it's one bit wider). this also avoids
the need to save the tid and pass it to locking_getc or locking_putc,
reducing register pressure.
this change might slightly hurt the case where the caller already
holds the lock, but it does not affect the single-threaded case, and
may significantly improve the multi-threaded case, especially on archs
where loading the thread pointer is disproportionately expensive like
early mips and arm ISA levels. but even on i386 it helps, at least on
some machines; I measured roughly a 10-15% improvement.
| Rich Felker | 2 | -10/+10 |
| 2018-10-18 | use prototype for function pointer in static link libc init barrier•••this is not needed for correctness, but doesn't hurt, and in some
cases the compiler may pessimize the call assuming the callee might be
variadic when it lacks a prototype.
| Rich Felker | 1 | -1/+1 |
| 2018-10-18 | fix error in constraints for static link libc init barrier•••commit 4390383b32250a941ec616e8bff6f568a801b1c0 inadvertently used "r"
instead of "0" for the input constraint, which only happened to work
for the configuration I tested it on because it usually makes sense
for the compiler to choose the same input and output register.
| Rich Felker | 1 | -1/+1 |
