[PATCH-for-5.0 v2 2/2] gdbstub: Introduce gdb_get_float64() to get 64-bit float registers

["Philippe Mathieu-Daudé" <philmd@redhat.com>]

When converted to use GByteArray in commits 462474d760c and
a010bdbe719, the call to stfq_p() was removed. This call
serialize a float.
Since we now use a GByteArray, we can not use stfq_p() directly.
Introduce the gdb_get_float64() helper to load a float64 register.

Fixes: 462474d760c ("target/m68k: use gdb_get_reg helpers")
Fixes: a010bdbe719 ("extend GByteArray to read register helpers")
Signed-off-by: Philippe Mathieu-Daudé <philmd@redhat.com>
---
 include/exec/gdbstub.h          | 12 ++++++++++++
 target/m68k/helper.c            |  3 ++-
 target/ppc/gdbstub.c            |  4 ++--
 target/ppc/translate_init.inc.c |  2 +-
 4 files changed, 17 insertions(+), 4 deletions(-)

diff --git a/include/exec/gdbstub.h b/include/exec/gdbstub.h
index 3caca99416..ef88cefbf6 100644
--- a/include/exec/gdbstub.h
+++ b/include/exec/gdbstub.h
@@ -137,6 +137,18 @@ static inline int gdb_get_float32(GByteArray *array, float32 val)
     return sizeof(buf);
 }
 
+static inline int gdb_get_float64(GByteArray *array, float64 val)
+{
+    uint8_t buf[8];
+
+    QEMU_BUILD_BUG_ON(sizeof(CPU_DoubleU) != sizeof(buf));
+
+    stfq_p(buf, val);
+    g_byte_array_append(array, buf, sizeof(buf));
+
+    return sizeof(buf);
+}
+
 static inline int gdb_get_zeroes(GByteArray *array, size_t len)
 {
     for (size_t i = 0; i < len; i++) {
diff --git a/target/m68k/helper.c b/target/m68k/helper.c
index 014657c637..cc80b48dda 100644
--- a/target/m68k/helper.c
+++ b/target/m68k/helper.c
@@ -72,7 +72,8 @@ static int cf_fpu_gdb_get_reg(CPUM68KState *env, GByteArray *mem_buf, int n)
 {
     if (n < 8) {
         float_status s;
-        return gdb_get_reg64(mem_buf, floatx80_to_float64(env->fregs[n].d, &s));
+        return gdb_get_float64(mem_buf,
+                               floatx80_to_float64(env->fregs[n].d, &s));
     }
     switch (n) {
     case 8: /* fpcontrol */
diff --git a/target/ppc/gdbstub.c b/target/ppc/gdbstub.c
index eb362dd9ae..5c11c88b2a 100644
--- a/target/ppc/gdbstub.c
+++ b/target/ppc/gdbstub.c
@@ -130,7 +130,7 @@ int ppc_cpu_gdb_read_register(CPUState *cs, GByteArray *buf, int n)
         gdb_get_regl(buf, env->gpr[n]);
     } else if (n < 64) {
         /* fprs */
-        gdb_get_reg64(buf, *cpu_fpr_ptr(env, n - 32));
+        gdb_get_float64(buf, *cpu_fpr_ptr(env, n - 32));
     } else {
         switch (n) {
         case 64:
@@ -184,7 +184,7 @@ int ppc_cpu_gdb_read_register_apple(CPUState *cs, GByteArray *buf, int n)
         gdb_get_reg64(buf, env->gpr[n]);
     } else if (n < 64) {
         /* fprs */
-        gdb_get_reg64(buf, *cpu_fpr_ptr(env, n - 32));
+        gdb_get_float64(buf, *cpu_fpr_ptr(env, n - 32));
     } else if (n < 96) {
         /* Altivec */
         gdb_get_reg64(buf, n - 64);
diff --git a/target/ppc/translate_init.inc.c b/target/ppc/translate_init.inc.c
index e853164a86..d825cb5975 100644
--- a/target/ppc/translate_init.inc.c
+++ b/target/ppc/translate_init.inc.c
@@ -9881,7 +9881,7 @@ static int gdb_get_float_reg(CPUPPCState *env, GByteArray *buf, int n)
 {
     uint8_t *mem_buf;
     if (n < 32) {
-        gdb_get_reg64(buf, *cpu_fpr_ptr(env, n));
+        gdb_get_float64(buf, *cpu_fpr_ptr(env, n));
         mem_buf = gdb_get_reg_ptr(buf, 8);
         ppc_maybe_bswap_register(env, mem_buf, 8);
         return 8;
-- 
2.21.1