target/mips: Extract FPU helpers to 'fpu_helper.h'

Extract FPU specific helpers from "internal.h" to "fpu_helper.h".

Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Message-Id: <20201120210844.2625602-2-f4bug@amsat.org>

1 files changed, 59 insertions, 0 deletions

diff --git a/target/mips/fpu_helper.h b/target/mips/fpu_helper.h
new file mode 100644
index 0000000..1c2d6d3
--- /dev/null
+++ b/target/mips/fpu_helper.h
@@ -0,0 +1,59 @@
+/*
+ * Helpers for emulation of FPU-related MIPS instructions.
+ *
+ *  Copyright (C) 2004-2005  Jocelyn Mayer
+ *
+ * SPDX-License-Identifier: LGPL-2.1-or-later
+ */
+#include "fpu/softfloat-helpers.h"
+#include "cpu.h"
+
+extern const FloatRoundMode ieee_rm[4];
+
+uint32_t float_class_s(uint32_t arg, float_status *fst);
+uint64_t float_class_d(uint64_t arg, float_status *fst);
+
+static inline void restore_rounding_mode(CPUMIPSState *env)
+{
+    set_float_rounding_mode(ieee_rm[env->active_fpu.fcr31 & 3],
+                            &env->active_fpu.fp_status);
+}
+
+static inline void restore_flush_mode(CPUMIPSState *env)
+{
+    set_flush_to_zero((env->active_fpu.fcr31 & (1 << FCR31_FS)) != 0,
+                      &env->active_fpu.fp_status);
+}
+
+static inline void restore_snan_bit_mode(CPUMIPSState *env)
+{
+    set_snan_bit_is_one((env->active_fpu.fcr31 & (1 << FCR31_NAN2008)) == 0,
+                        &env->active_fpu.fp_status);
+}
+
+static inline void restore_fp_status(CPUMIPSState *env)
+{
+    restore_rounding_mode(env);
+    restore_flush_mode(env);
+    restore_snan_bit_mode(env);
+}
+
+/* MSA */
+
+enum CPUMIPSMSADataFormat {
+    DF_BYTE = 0,
+    DF_HALF,
+    DF_WORD,
+    DF_DOUBLE
+};
+
+static inline void restore_msa_fp_status(CPUMIPSState *env)
+{
+    float_status *status = &env->active_tc.msa_fp_status;
+    int rounding_mode = (env->active_tc.msacsr & MSACSR_RM_MASK) >> MSACSR_RM;
+    bool flush_to_zero = (env->active_tc.msacsr & MSACSR_FS_MASK) != 0;
+
+    set_float_rounding_mode(ieee_rm[rounding_mode], status);
+    set_flush_to_zero(flush_to_zero, status);
+    set_flush_inputs_to_zero(flush_to_zero, status);
+}