From 0c30e0f3160716430de36f359cd120aa875dcb82 Mon Sep 17 00:00:00 2001 From: Evandro Menezes Date: Fri, 26 Feb 2016 23:41:53 +0000 Subject: Rename the tuning option and related functions to enable the Newton series for the reciprocal square root to reflect its approximative characteristic. gcc/ * config/aarch64/aarch64-protos.h (aarch64_emit_swrsqrt): Rename function to "aarch64_emit_approx_rsqrt". * config/aarch64/aarch64-tuning-flags.def: Rename tuning flag to AARCH64_EXTRA_TUNE_APPROX_RSQRT. * config/aarch64/aarch64.c (exynosm1_tunigs): Use new flag name. (xgene1_tunings): Likewise. (use_rsqrt_p): Likewise. (aarch64_emit_swrsqrt): Use new function name. * config/aarch64/aarch64-simd.md (aarch64_rsqrts_*): Likewise. * config/aarch64/aarch64.opt (mlow-precision-recip-sqrt): Reword the text explaining this option. * doc/invoke.texi (-mlow-precision-recip-sqrt): Likewise. From-SVN: r233772 --- gcc/doc/invoke.texi | 10 ++++------ 1 file changed, 4 insertions(+), 6 deletions(-) (limited to 'gcc/doc') diff --git a/gcc/doc/invoke.texi b/gcc/doc/invoke.texi index 18b2b8f..4b5df0b 100644 --- a/gcc/doc/invoke.texi +++ b/gcc/doc/invoke.texi @@ -12884,12 +12884,10 @@ corresponding flag to the linker. @item -mno-low-precision-recip-sqrt @opindex -mlow-precision-recip-sqrt @opindex -mno-low-precision-recip-sqrt -The square root estimate uses two steps instead of three for double-precision, -and one step instead of two for single-precision. -Thus reducing latency and precision. -This is only relevant if @option{-ffast-math} activates -reciprocal square root estimate instructions. -Which in turn depends on the target processor. +When calculating the reciprocal square root approximation, +uses one less step than otherwise, thus reducing latency and precision. +This is only relevant if @option{-ffast-math} enables the reciprocal square root +approximation, which in turn depends on the target processor. @item -march=@var{name} @opindex march -- cgit v1.1