Patchwork [6/9] target-sh4: implement flush-to-zero

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Submitter Aurelien Jarno
Date Jan. 11, 2011, 9:01 p.m.
Message ID <1294779698-17694-7-git-send-email-aurelien@aurel32.net>
Download mbox | patch
Permalink /patch/78432/
State New
Headers show

Comments

Aurelien Jarno - Jan. 11, 2011, 9:01 p.m.
When the FPSCR.DN bit is set, the SH4 FPU treat denormalized numbers as
zero. Enable the corresponding softfloat option when this bit is set.

Signed-off-by: Aurelien Jarno <aurelien@aurel32.net>
---
 target-sh4/op_helper.c |    1 +
 target-sh4/translate.c |    1 +
 2 files changed, 2 insertions(+), 0 deletions(-)

Patch

diff --git a/target-sh4/op_helper.c b/target-sh4/op_helper.c
index 9915e42..76a40bd 100644
--- a/target-sh4/op_helper.c
+++ b/target-sh4/op_helper.c
@@ -434,6 +434,7 @@  void helper_ld_fpscr(uint32_t val)
     } else {
 	set_float_rounding_mode(float_round_nearest_even, &env->fp_status);
     }
+    set_flush_to_zero((val & FPSCR_DN) != 0, &env->fp_status);
 }
 
 uint32_t helper_fabs_FT(uint32_t t0)
diff --git a/target-sh4/translate.c b/target-sh4/translate.c
index bdfa31a..080ff6e 100644
--- a/target-sh4/translate.c
+++ b/target-sh4/translate.c
@@ -205,6 +205,7 @@  static void cpu_sh4_reset(CPUSH4State * env)
 #else
     env->fpscr = FPSCR_DN | FPSCR_RM_ZERO; /* CPU reset value according to SH4 manual */
     set_float_rounding_mode(float_round_to_zero, &env->fp_status);
+    set_flush_to_zero(1, &env->fp_status);
 #endif
     set_default_nan_mode(1, &env->fp_status);
     env->mmucr = 0;