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From: Richard Henderson <richard.henderson@linaro.org>
To: qemu-devel@nongnu.org
Cc: alex.bennee@linaro.org, mmorrell@tachyum.com
Subject: [PATCH 03/11] softfloat: Introduce float_flag_inorm_denormal
Date: Wed, 26 May 2021 21:13:57 -0700	[thread overview]
Message-ID: <20210527041405.391567-4-richard.henderson@linaro.org> (raw)
In-Reply-To: <20210527041405.391567-1-richard.henderson@linaro.org>

Create a new exception flag for reporting input denormals that are not
flushed to zero, they are normalized and treated as normal numbers.

Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
---
 include/fpu/softfloat-types.h | 15 ++++---
 fpu/softfloat.c               | 84 +++++++++++------------------------
 fpu/softfloat-parts.c.inc     |  1 +
 3 files changed, 36 insertions(+), 64 deletions(-)

diff --git a/include/fpu/softfloat-types.h b/include/fpu/softfloat-types.h
index e2d70ff556..174100e50e 100644
--- a/include/fpu/softfloat-types.h
+++ b/include/fpu/softfloat-types.h
@@ -143,13 +143,14 @@ typedef enum __attribute__((__packed__)) {
  */
 
 enum {
-    float_flag_invalid   =  1,
-    float_flag_divbyzero =  4,
-    float_flag_overflow  =  8,
-    float_flag_underflow = 16,
-    float_flag_inexact   = 32,
-    float_flag_iflush_denormal = 64,
-    float_flag_oflush_denormal = 128
+    float_flag_invalid         = 0x0001,
+    float_flag_divbyzero       = 0x0002,
+    float_flag_overflow        = 0x0004,
+    float_flag_underflow       = 0x0008,
+    float_flag_inexact         = 0x0010,
+    float_flag_inorm_denormal  = 0x0020,  /* denormal input, normalized */
+    float_flag_iflush_denormal = 0x0040,  /* denormal input, flushed to zero */
+    float_flag_oflush_denormal = 0x0080,  /* denormal result, flushed to zero */
 };
 
 /*
diff --git a/fpu/softfloat.c b/fpu/softfloat.c
index cb077cf111..e54cdb274d 100644
--- a/fpu/softfloat.c
+++ b/fpu/softfloat.c
@@ -126,61 +126,23 @@ this code that are retained.
  * denormal/inf/NaN; (2) when operands are not guaranteed to lead to a 0 result
  * and the result is < the minimum normal.
  */
-#define GEN_INPUT_FLUSH__NOCHECK(name, soft_t)                          \
+
+#define GEN_INPUT_FLUSH(name, soft_t)                                   \
     static inline void name(soft_t *a, float_status *s)                 \
     {                                                                   \
         if (unlikely(soft_t ## _is_denormal(*a))) {                     \
-            *a = soft_t ## _set_sign(soft_t ## _zero,                   \
-                                     soft_t ## _is_neg(*a));            \
-            float_raise(float_flag_iflush_denormal, s);                  \
+            if (s->flush_inputs_to_zero) {                              \
+                *a = soft_t ## _set_sign(0, soft_t ## _is_neg(*a));     \
+                float_raise(float_flag_iflush_denormal, s);             \
+            } else {                                                    \
+                float_raise(float_flag_inorm_denormal, s);              \
+            }                                                           \
         }                                                               \
     }
 
-GEN_INPUT_FLUSH__NOCHECK(float32_input_flush__nocheck, float32)
-GEN_INPUT_FLUSH__NOCHECK(float64_input_flush__nocheck, float64)
-#undef GEN_INPUT_FLUSH__NOCHECK
-
-#define GEN_INPUT_FLUSH1(name, soft_t)                  \
-    static inline void name(soft_t *a, float_status *s) \
-    {                                                   \
-        if (likely(!s->flush_inputs_to_zero)) {         \
-            return;                                     \
-        }                                               \
-        soft_t ## _input_flush__nocheck(a, s);          \
-    }
-
-GEN_INPUT_FLUSH1(float32_input_flush1, float32)
-GEN_INPUT_FLUSH1(float64_input_flush1, float64)
-#undef GEN_INPUT_FLUSH1
-
-#define GEN_INPUT_FLUSH2(name, soft_t)                                  \
-    static inline void name(soft_t *a, soft_t *b, float_status *s)      \
-    {                                                                   \
-        if (likely(!s->flush_inputs_to_zero)) {                         \
-            return;                                                     \
-        }                                                               \
-        soft_t ## _input_flush__nocheck(a, s);                          \
-        soft_t ## _input_flush__nocheck(b, s);                          \
-    }
-
-GEN_INPUT_FLUSH2(float32_input_flush2, float32)
-GEN_INPUT_FLUSH2(float64_input_flush2, float64)
-#undef GEN_INPUT_FLUSH2
-
-#define GEN_INPUT_FLUSH3(name, soft_t)                                  \
-    static inline void name(soft_t *a, soft_t *b, soft_t *c, float_status *s) \
-    {                                                                   \
-        if (likely(!s->flush_inputs_to_zero)) {                         \
-            return;                                                     \
-        }                                                               \
-        soft_t ## _input_flush__nocheck(a, s);                          \
-        soft_t ## _input_flush__nocheck(b, s);                          \
-        soft_t ## _input_flush__nocheck(c, s);                          \
-    }
-
-GEN_INPUT_FLUSH3(float32_input_flush3, float32)
-GEN_INPUT_FLUSH3(float64_input_flush3, float64)
-#undef GEN_INPUT_FLUSH3
+GEN_INPUT_FLUSH(float32_input_flush, float32)
+GEN_INPUT_FLUSH(float64_input_flush, float64)
+#undef GEN_INPUT_FLUSH
 
 /*
  * Choose whether to use fpclassify or float32/64_* primitives in the generated
@@ -353,7 +315,8 @@ float32_gen2(float32 xa, float32 xb, float_status *s,
         goto soft;
     }
 
-    float32_input_flush2(&ua.s, &ub.s, s);
+    float32_input_flush(&ua.s, s);
+    float32_input_flush(&ub.s, s);
     if (unlikely(!pre(ua, ub))) {
         goto soft;
     }
@@ -384,7 +347,8 @@ float64_gen2(float64 xa, float64 xb, float_status *s,
         goto soft;
     }
 
-    float64_input_flush2(&ua.s, &ub.s, s);
+    float64_input_flush(&ua.s, s);
+    float64_input_flush(&ub.s, s);
     if (unlikely(!pre(ua, ub))) {
         goto soft;
     }
@@ -2161,7 +2125,9 @@ float32_muladd(float32 xa, float32 xb, float32 xc, int flags, float_status *s)
         goto soft;
     }
 
-    float32_input_flush3(&ua.s, &ub.s, &uc.s, s);
+    float32_input_flush(&ua.s, s);
+    float32_input_flush(&ub.s, s);
+    float32_input_flush(&uc.s, s);
     if (unlikely(!f32_is_zon3(ua, ub, uc))) {
         goto soft;
     }
@@ -2232,7 +2198,9 @@ float64_muladd(float64 xa, float64 xb, float64 xc, int flags, float_status *s)
         goto soft;
     }
 
-    float64_input_flush3(&ua.s, &ub.s, &uc.s, s);
+    float64_input_flush(&ua.s, s);
+    float64_input_flush(&ub.s, s);
+    float64_input_flush(&uc.s, s);
     if (unlikely(!f64_is_zon3(ua, ub, uc))) {
         goto soft;
     }
@@ -3988,7 +3956,8 @@ float32_hs_compare(float32 xa, float32 xb, float_status *s, bool is_quiet)
         goto soft;
     }
 
-    float32_input_flush2(&ua.s, &ub.s, s);
+    float32_input_flush(&ua.s, s);
+    float32_input_flush(&ub.s, s);
     if (isgreaterequal(ua.h, ub.h)) {
         if (isgreater(ua.h, ub.h)) {
             return float_relation_greater;
@@ -4038,7 +4007,8 @@ float64_hs_compare(float64 xa, float64 xb, float_status *s, bool is_quiet)
         goto soft;
     }
 
-    float64_input_flush2(&ua.s, &ub.s, s);
+    float64_input_flush(&ua.s, s);
+    float64_input_flush(&ub.s, s);
     if (isgreaterequal(ua.h, ub.h)) {
         if (isgreater(ua.h, ub.h)) {
             return float_relation_greater;
@@ -4230,7 +4200,7 @@ float32 QEMU_FLATTEN float32_sqrt(float32 xa, float_status *s)
         goto soft;
     }
 
-    float32_input_flush1(&ua.s, s);
+    float32_input_flush(&ua.s, s);
     if (QEMU_HARDFLOAT_1F32_USE_FP) {
         if (unlikely(!(fpclassify(ua.h) == FP_NORMAL ||
                        fpclassify(ua.h) == FP_ZERO) ||
@@ -4257,7 +4227,7 @@ float64 QEMU_FLATTEN float64_sqrt(float64 xa, float_status *s)
         goto soft;
     }
 
-    float64_input_flush1(&ua.s, s);
+    float64_input_flush(&ua.s, s);
     if (QEMU_HARDFLOAT_1F64_USE_FP) {
         if (unlikely(!(fpclassify(ua.h) == FP_NORMAL ||
                        fpclassify(ua.h) == FP_ZERO) ||
diff --git a/fpu/softfloat-parts.c.inc b/fpu/softfloat-parts.c.inc
index 72e2b24539..16d4425419 100644
--- a/fpu/softfloat-parts.c.inc
+++ b/fpu/softfloat-parts.c.inc
@@ -119,6 +119,7 @@ static void partsN(canonicalize)(FloatPartsN *p, float_status *status,
             int shift = frac_normalize(p);
             p->cls = float_class_normal;
             p->exp = fmt->frac_shift - fmt->exp_bias - shift + 1;
+            float_raise(float_flag_inorm_denormal, status);
         }
     } else if (likely(p->exp < fmt->exp_max) || fmt->arm_althp) {
         p->cls = float_class_normal;
-- 
2.25.1



  parent reply	other threads:[~2021-05-27  4:18 UTC|newest]

Thread overview: 38+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2021-05-27  4:13 [PATCH 00/11] softfloat: Improve denormal handling Richard Henderson
2021-05-27  4:13 ` [PATCH 01/11] softfloat: Rename float_flag_input_denormal to float_flag_iflush_denormal Richard Henderson
2021-06-07 15:16   ` Alex Bennée
2021-06-19 15:08   ` Philippe Mathieu-Daudé
2021-05-27  4:13 ` [PATCH 02/11] softfloat: Rename float_flag_output_denormal to float_flag_oflush_denormal Richard Henderson
2021-06-07 15:16   ` Alex Bennée
2021-06-19 15:08   ` Philippe Mathieu-Daudé
2021-05-27  4:13 ` Richard Henderson [this message]
2021-05-28 17:41   ` [PATCH 03/11] softfloat: Introduce float_flag_inorm_denormal Michael Morrell
2021-05-29 15:21     ` Richard Henderson
2021-07-14 16:44       ` Michael Morrell
2021-07-14 16:57         ` Richard Henderson
2021-07-14 17:50           ` Michael Morrell
2022-01-12  0:02             ` Michael Morrell
2021-06-07 15:35   ` Alex Bennée
2021-06-07 16:28     ` Alex Bennée
2021-06-07 16:41     ` Richard Henderson
2021-06-07 17:19       ` Alex Bennée
2021-06-07 20:52         ` Richard Henderson
2021-05-27  4:13 ` [PATCH 04/11] softfloat: Introduce float_flag_result_denormal Richard Henderson
2021-06-07 16:30   ` Alex Bennée
2021-06-19 15:10   ` Philippe Mathieu-Daudé
2021-05-27  4:13 ` [PATCH 05/11] target/i386: Use float_flag_inorm_denormal Richard Henderson
2021-06-19 18:41   ` Richard Henderson
2021-05-27  4:14 ` [PATCH 06/11] target/rx: Handle the FPSW.DN bit in helper_set_fpsw Richard Henderson
2021-05-28 15:34   ` Yoshinori Sato
2021-05-27  4:14 ` [PATCH 07/11] target/rx: Use FloatRoundMode " Richard Henderson
2021-05-28 15:35   ` Yoshinori Sato
2021-06-01  3:27   ` Philippe Mathieu-Daudé
2021-05-27  4:14 ` [PATCH 08/11] target/rx: Fix setting of FPSW.CE Richard Henderson
2021-05-28 15:35   ` Yoshinori Sato
2021-05-27  4:14 ` [PATCH 09/11] target/mips: Drop inline markers from msa_helper.c Richard Henderson
2021-06-01  3:27   ` Philippe Mathieu-Daudé
2021-05-27  4:14 ` [PATCH 10/11] target/mips: Do not check MSACSR_FS_MASK in update_msacsr Richard Henderson
2021-06-19 15:15   ` Philippe Mathieu-Daudé
2021-05-27  4:14 ` [PATCH 11/11] target/mips: Drop denormal operand to update_msacsr Richard Henderson
2021-06-01  3:29   ` Philippe Mathieu-Daudé
2021-06-07 16:31 ` [PATCH 00/11] softfloat: Improve denormal handling Alex Bennée

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