dump: Introduce dump_is_64bit() helper function

Checking d_class in dump_info leads to lengthy conditionals so let's
shorten things a bit by introducing a helper function.

Signed-off-by: Janosch Frank <frankja@linux.ibm.com>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Message-Id: <20220330123603.107120-7-frankja@linux.ibm.com>

dump/dump.c

@@ -54,6 +54,11 @@ static Error *dump_migration_blocker;
       DIV_ROUND_UP((name_size), 4) +                    \
       DIV_ROUND_UP((desc_size), 4)) * 4)
 
+static inline bool dump_is_64bit(DumpState *s)
+{
+    return s->dump_info.d_class == ELFCLASS64;
+}
+
 uint16_t cpu_to_dump16(DumpState *s, uint16_t val)
 {
     if (s->dump_info.d_endian == ELFDATA2LSB) {
@@ -488,7 +493,7 @@ static void write_elf_loads(DumpState *s, Error **errp)
         get_offset_range(memory_mapping->phys_addr,
                          memory_mapping->length,
                          s, &offset, &filesz);
-        if (s->dump_info.d_class == ELFCLASS64) {
+        if (dump_is_64bit(s)) {
             write_elf64_load(s, memory_mapping, phdr_index++, offset,
                              filesz, errp);
         } else {
@@ -536,7 +541,7 @@ static void dump_begin(DumpState *s, Error **errp)
      */
 
     /* write elf header to vmcore */
-    if (s->dump_info.d_class == ELFCLASS64) {
+    if (dump_is_64bit(s)) {
         write_elf64_header(s, errp);
     } else {
         write_elf32_header(s, errp);
@@ -545,7 +550,7 @@ static void dump_begin(DumpState *s, Error **errp)
         return;
     }
 
-    if (s->dump_info.d_class == ELFCLASS64) {
+    if (dump_is_64bit(s)) {
         /* write PT_NOTE to vmcore */
         write_elf64_note(s, errp);
         if (*errp) {
@@ -756,7 +761,7 @@ static void get_note_sizes(DumpState *s, const void *note,
     uint64_t name_sz;
     uint64_t desc_sz;
 
-    if (s->dump_info.d_class == ELFCLASS64) {
+    if (dump_is_64bit(s)) {
         const Elf64_Nhdr *hdr = note;
         note_head_sz = sizeof(Elf64_Nhdr);
         name_sz = tswap64(hdr->n_namesz);
@@ -1016,10 +1021,10 @@ static void create_header64(DumpState *s, Error **errp)
 
 static void write_dump_header(DumpState *s, Error **errp)
 {
-    if (s->dump_info.d_class == ELFCLASS32) {
-        create_header32(s, errp);
-    } else {
+    if (dump_is_64bit(s)) {
         create_header64(s, errp);
+    } else {
+        create_header32(s, errp);
     }
 }
 
@@ -1706,8 +1711,8 @@ static void dump_init(DumpState *s, int fd, bool has_format,
         uint32_t size;
         uint16_t format;
 
-        note_head_size = s->dump_info.d_class == ELFCLASS32 ?
-            sizeof(Elf32_Nhdr) : sizeof(Elf64_Nhdr);
+        note_head_size = dump_is_64bit(s) ?
+            sizeof(Elf64_Nhdr) : sizeof(Elf32_Nhdr);
 
         format = le16_to_cpu(vmci->vmcoreinfo.guest_format);
         size = le32_to_cpu(vmci->vmcoreinfo.size);
@@ -1810,7 +1815,7 @@ static void dump_init(DumpState *s, int fd, bool has_format,
         }
     }
 
-    if (s->dump_info.d_class == ELFCLASS64) {
+    if (dump_is_64bit(s)) {
         s->phdr_offset = sizeof(Elf64_Ehdr);
         s->shdr_offset = s->phdr_offset + sizeof(Elf64_Phdr) * s->phdr_num;
         s->note_offset = s->shdr_offset + sizeof(Elf64_Shdr) * s->shdr_num;