diff options
Diffstat (limited to 'gcc/config/aarch64/aarch64.c')
| -rw-r--r-- | gcc/config/aarch64/aarch64.c | 23 |
1 files changed, 12 insertions, 11 deletions
diff --git a/gcc/config/aarch64/aarch64.c b/gcc/config/aarch64/aarch64.c index 3519c7b..801f95a 100644 --- a/gcc/config/aarch64/aarch64.c +++ b/gcc/config/aarch64/aarch64.c @@ -538,7 +538,7 @@ static const struct tune_params exynosm1_tunings = 48, /* max_case_values. */ 64, /* cache_line_size. */ tune_params::AUTOPREFETCHER_OFF, /* autoprefetcher_model. */ - (AARCH64_EXTRA_TUNE_RECIP_SQRT) /* tune_flags. */ + (AARCH64_EXTRA_TUNE_APPROX_RSQRT) /* tune_flags. */ }; static const struct tune_params thunderx_tunings = @@ -586,7 +586,7 @@ static const struct tune_params xgene1_tunings = 0, /* max_case_values. */ 0, /* cache_line_size. */ tune_params::AUTOPREFETCHER_OFF, /* autoprefetcher_model. */ - (AARCH64_EXTRA_TUNE_RECIP_SQRT) /* tune_flags. */ + (AARCH64_EXTRA_TUNE_APPROX_RSQRT) /* tune_flags. */ }; /* Support for fine-grained override of the tuning structures. */ @@ -7460,8 +7460,8 @@ aarch64_memory_move_cost (machine_mode mode ATTRIBUTE_UNUSED, return aarch64_tune_params.memmov_cost; } -/* Return true if it is safe and beneficial to use the rsqrt optabs to - optimize 1.0/sqrt. */ +/* Return true if it is safe and beneficial to use the approximate rsqrt optabs + to optimize 1.0/sqrt. */ static bool use_rsqrt_p (void) @@ -7469,12 +7469,12 @@ use_rsqrt_p (void) return (!flag_trapping_math && flag_unsafe_math_optimizations && ((aarch64_tune_params.extra_tuning_flags - & AARCH64_EXTRA_TUNE_RECIP_SQRT) + & AARCH64_EXTRA_TUNE_APPROX_RSQRT) || flag_mrecip_low_precision_sqrt)); } -/* Function to decide when to use - reciprocal square root builtins. */ +/* Function to decide when to use the approximate reciprocal square root + builtin. */ static tree aarch64_builtin_reciprocal (tree fndecl) @@ -7522,12 +7522,12 @@ get_rsqrts_type (machine_mode mode) } } -/* Emit instruction sequence to compute - reciprocal square root. Use two Newton-Raphson steps - for single precision and three for double precision. */ +/* Emit instruction sequence to compute the reciprocal square root using the + Newton-Raphson series. Iterate over the series twice for SF + and thrice for DF. */ void -aarch64_emit_swrsqrt (rtx dst, rtx src) +aarch64_emit_approx_rsqrt (rtx dst, rtx src) { machine_mode mode = GET_MODE (src); gcc_assert ( @@ -7544,6 +7544,7 @@ aarch64_emit_swrsqrt (rtx dst, rtx src) int iterations = double_mode ? 3 : 2; + /* Optionally iterate over the series one less time than otherwise. */ if (flag_mrecip_low_precision_sqrt) iterations--; |