On Mon, May 21, 2012 at 1:14 AM, Alan Modra <amo...@gmail.com> wrote: > Currently, powerpc-linux gcc -Os -mno-multiple uses out-of-line gpr > save and restore functions when saving/restoring just one gpr. That's > quite silly since the function call requires more instructions and is > slower than an inline save/restore. The only case where it might win > is when no fprs are restored and the restore function can tear down > the frame and exit (also loading up lr on ppc64). I guess that's how > GP_SAVE_INLINE came to be like it is, ie. it's optimised for the > common case using ldm in the prologue and no fprs. Still, it isn't > difficult to choose the best combination in all cases, but it does > mean different logic is needed for restores. I could have implemented > GP_RESTORE_INLINE and FP_RESORE_INLINE macros but it seemed simpler to > just move everything into the one place the macros are invoked. AIX > and Darwin register cutoff doesn't change with this patch. > > This patch also enables out-of-line restores in cases that were > previously disabled due to using inline saves. > > Bootstrapped and regression tested powerpc-linux. OK to apply? > > * aix.h (FP_SAVE_INLINE, GP_SAVE_INLINE): Delete. > * darwin.h (FP_SAVE_INLINE, GP_SAVE_INLINE): Delete. > * sysv4.h (FP_SAVE_INLINE, GP_SAVE_INLINE, V_SAVE_INLINE): Delete. > * config/rs6000/rs6000.c (V_SAVE_INLINE): Delete. > (rs6000_savres_strategy): Reimplement GP/FP/V_SAVE_INLINE logic. > For ELF targets, use out-of-line restores for -Os and any number > of regs if the restore exits, and out-of-line gp save for two or > more regs. Use save_reg_p to test for holes in reg restore set. > Replace "#if" with "if".
Okay. Thanks, David
