Rather than repeatedly copying FPST_FPCR to locals
and setting default nan mode, create dedicated float_status.
Signed-off-by: Richard Henderson <richard.hender...@linaro.org>
---
target/arm/cpu.h | 12 +++++++++++-
target/arm/cpu.c | 4 ++++
target/arm/vfp_helper.c | 10 ++++++++++
3 files changed, 25 insertions(+), 1 deletion(-)
diff --git a/target/arm/cpu.h b/target/arm/cpu.h
index e6513ef1e5..42c39ac6bd 100644
--- a/target/arm/cpu.h
+++ b/target/arm/cpu.h
@@ -219,6 +219,8 @@ typedef struct NVICState NVICState;
* when FPCR.AH == 1 (bfloat16 conversions and multiplies,
* and the reciprocal and square root estimate/step insns);
* for half-precision
+ * ZA: the "streaming sve" fp status.
+ * ZA_F16: likewise for half-precision.
*
* Half-precision operations are governed by a separate
* flush-to-zero control bit in FPSCR:FZ16. We pass a separate
@@ -239,6 +241,12 @@ typedef struct NVICState NVICState;
* they ignore FPCR.RMode. But they don't ignore FPCR.FZ16,
* which means we need an FPST_AH_F16 as well.
*
+ * The "ZA" float_status are for Streaming SVE operations which use
+ * default-NaN and do not generate fp exceptions, which means that they
+ * do not accumulate exception bits back into FPCR.
+ * See e.g. FPAdd vs FPAdd_ZA pseudocode functions, and the setting
+ * of fpcr.DN and fpexec parameters.
+ *
* To avoid having to transfer exception bits around, we simply
* say that the FPSCR cumulative exception flags are the logical
* OR of the flags in the four fp statuses. This relies on the
@@ -252,10 +260,12 @@ typedef enum ARMFPStatusFlavour {
FPST_A64_F16,
FPST_AH,
FPST_AH_F16,
+ FPST_ZA,
+ FPST_ZA_F16,
FPST_STD,
FPST_STD_F16,
} ARMFPStatusFlavour;
-#define FPST_COUNT 8
+#define FPST_COUNT 10
typedef struct CPUArchState {
/* Regs for current mode. */
diff --git a/target/arm/cpu.c b/target/arm/cpu.c
index 180e11c5d7..ba08c05ec6 100644
--- a/target/arm/cpu.c
+++ b/target/arm/cpu.c
@@ -550,11 +550,15 @@ static void arm_cpu_reset_hold(Object *obj, ResetType
type)
set_flush_inputs_to_zero(1, &env->vfp.fp_status[FPST_STD]);
set_default_nan_mode(1, &env->vfp.fp_status[FPST_STD]);
set_default_nan_mode(1, &env->vfp.fp_status[FPST_STD_F16]);
+ set_default_nan_mode(1, &env->vfp.fp_status[FPST_ZA]);
+ set_default_nan_mode(1, &env->vfp.fp_status[FPST_ZA_F16]);
arm_set_default_fp_behaviours(&env->vfp.fp_status[FPST_A32]);
arm_set_default_fp_behaviours(&env->vfp.fp_status[FPST_A64]);
+ arm_set_default_fp_behaviours(&env->vfp.fp_status[FPST_ZA]);
arm_set_default_fp_behaviours(&env->vfp.fp_status[FPST_STD]);
arm_set_default_fp_behaviours(&env->vfp.fp_status[FPST_A32_F16]);
arm_set_default_fp_behaviours(&env->vfp.fp_status[FPST_A64_F16]);
+ arm_set_default_fp_behaviours(&env->vfp.fp_status[FPST_ZA_F16]);
arm_set_default_fp_behaviours(&env->vfp.fp_status[FPST_STD_F16]);
arm_set_ah_fp_behaviours(&env->vfp.fp_status[FPST_AH]);
set_flush_to_zero(1, &env->vfp.fp_status[FPST_AH]);
diff --git a/target/arm/vfp_helper.c b/target/arm/vfp_helper.c
index ff4b25bf28..f26c0d211e 100644
--- a/target/arm/vfp_helper.c
+++ b/target/arm/vfp_helper.c
@@ -202,6 +202,8 @@ static void vfp_set_fpcr_to_host(CPUARMState *env, uint32_t
val, uint32_t mask)
set_float_rounding_mode(i, &env->vfp.fp_status[FPST_A64]);
set_float_rounding_mode(i, &env->vfp.fp_status[FPST_A32_F16]);
set_float_rounding_mode(i, &env->vfp.fp_status[FPST_A64_F16]);
+ set_float_rounding_mode(i, &env->vfp.fp_status[FPST_ZA]);
+ set_float_rounding_mode(i, &env->vfp.fp_status[FPST_ZA_F16]);
}
if (changed & FPCR_FZ16) {
bool ftz_enabled = val & FPCR_FZ16;
@@ -209,15 +211,18 @@ static void vfp_set_fpcr_to_host(CPUARMState *env,
uint32_t val, uint32_t mask)
set_flush_to_zero(ftz_enabled, &env->vfp.fp_status[FPST_A64_F16]);
set_flush_to_zero(ftz_enabled, &env->vfp.fp_status[FPST_STD_F16]);
set_flush_to_zero(ftz_enabled, &env->vfp.fp_status[FPST_AH_F16]);
+ set_flush_to_zero(ftz_enabled, &env->vfp.fp_status[FPST_ZA_F16]);
set_flush_inputs_to_zero(ftz_enabled,
&env->vfp.fp_status[FPST_A32_F16]);
set_flush_inputs_to_zero(ftz_enabled,
&env->vfp.fp_status[FPST_A64_F16]);
set_flush_inputs_to_zero(ftz_enabled,
&env->vfp.fp_status[FPST_STD_F16]);
set_flush_inputs_to_zero(ftz_enabled,
&env->vfp.fp_status[FPST_AH_F16]);
+ set_flush_inputs_to_zero(ftz_enabled,
&env->vfp.fp_status[FPST_ZA_F16]);
}
if (changed & FPCR_FZ) {
bool ftz_enabled = val & FPCR_FZ;
set_flush_to_zero(ftz_enabled, &env->vfp.fp_status[FPST_A32]);
set_flush_to_zero(ftz_enabled, &env->vfp.fp_status[FPST_A64]);
+ set_flush_to_zero(ftz_enabled, &env->vfp.fp_status[FPST_ZA]);
/* FIZ is A64 only so FZ always makes A32 code flush inputs to zero */
set_flush_inputs_to_zero(ftz_enabled, &env->vfp.fp_status[FPST_A32]);
}
@@ -229,6 +234,7 @@ static void vfp_set_fpcr_to_host(CPUARMState *env, uint32_t
val, uint32_t mask)
bool fitz_enabled = (val & FPCR_FIZ) ||
(val & (FPCR_FZ | FPCR_AH)) == FPCR_FZ;
set_flush_inputs_to_zero(fitz_enabled, &env->vfp.fp_status[FPST_A64]);
+ set_flush_inputs_to_zero(fitz_enabled, &env->vfp.fp_status[FPST_ZA]);
}
if (changed & FPCR_DN) {
bool dnan_enabled = val & FPCR_DN;
@@ -246,9 +252,13 @@ static void vfp_set_fpcr_to_host(CPUARMState *env,
uint32_t val, uint32_t mask)
/* Change behaviours for A64 FP operations */
arm_set_ah_fp_behaviours(&env->vfp.fp_status[FPST_A64]);
arm_set_ah_fp_behaviours(&env->vfp.fp_status[FPST_A64_F16]);
+ arm_set_ah_fp_behaviours(&env->vfp.fp_status[FPST_ZA]);
+ arm_set_ah_fp_behaviours(&env->vfp.fp_status[FPST_ZA_F16]);
} else {
arm_set_default_fp_behaviours(&env->vfp.fp_status[FPST_A64]);
arm_set_default_fp_behaviours(&env->vfp.fp_status[FPST_A64_F16]);
+ arm_set_default_fp_behaviours(&env->vfp.fp_status[FPST_ZA]);
+ arm_set_default_fp_behaviours(&env->vfp.fp_status[FPST_ZA_F16]);
}
}
/*
--
2.43.0
