x86: Report expected register for elf_x86_tls_error_indirect_call

Since R_386_TLS_DESC_CALL can only be used with

	call	*variable@TLSCALL(%eax)

and R_X86_64_TLSDESC_CALL can only be used with

	call	*variable@TLSCALL(%rax)

update TLS transition error report to display the expected register in
indirect CALL.

bfd/

	PR ld/32017
	* elfxx-x86.c (_bfd_x86_elf_link_hash_table_create): Initialize
	the ax_register field.
	(_bfd_x86_elf_link_report_tls_transition_error): Report the
	expected register in elf_x86_tls_error_indirect_call error.
	* elfxx-x86.h (elf_x86_link_hash_table): Add ax_register.

ld/

	PR ld/32017
	* testsuite/ld-i386/tlsgdesc2.d: Updated.
	* testsuite/ld-i386/tlsgdesc2.s: Change jmp to call via ECX.
	* testsuite/ld-x86-64/tlsdesc4.d: Updated.
	* testsuite/ld-x86-64/tlsdesc4.s: Change jmp to call via RCX.

Signed-off-by: H.J. Lu <hjl.tools@gmail.com>

bfd/elfxx-x86.c

@@ -745,6 +745,7 @@ _bfd_x86_elf_link_hash_table_create (bfd *abfd)
       ret->tls_get_addr = "__tls_get_addr";
       ret->relative_r_type = R_X86_64_RELATIVE;
       ret->relative_r_name = "R_X86_64_RELATIVE";
+      ret->ax_register = "RAX";
       ret->elf_append_reloc = elf_append_rela;
       ret->elf_write_addend_in_got = _bfd_elf64_write_addend;
     }
@@ -776,6 +777,7 @@ _bfd_x86_elf_link_hash_table_create (bfd *abfd)
 	  ret->pointer_r_type = R_386_32;
 	  ret->relative_r_type = R_386_RELATIVE;
 	  ret->relative_r_name = "R_386_RELATIVE";
+	  ret->ax_register = "EAX";
 	  ret->elf_append_reloc = elf_append_rel;
 	  ret->elf_write_addend = _bfd_elf32_write_addend;
 	  ret->elf_write_addend_in_got = _bfd_elf32_write_addend;
@@ -3211,15 +3213,14 @@ _bfd_x86_elf_link_report_tls_transition_error
    enum elf_x86_tls_error_type tls_error)
 {
   const char *name;
+  const struct elf_backend_data *bed = get_elf_backend_data (abfd);
+  struct elf_x86_link_hash_table *htab
+    = elf_x86_hash_table (info, bed->target_id);
 
   if (h)
     name = h->root.root.string;
   else
     {
-      const struct elf_backend_data *bed
-	= get_elf_backend_data (abfd);
-      struct elf_x86_link_hash_table *htab
-	= elf_x86_hash_table (info, bed->target_id);
       if (htab == NULL)
 	name = "*unknown*";
       else
@@ -3265,8 +3266,9 @@ _bfd_x86_elf_link_report_tls_transition_error
       info->callbacks->einfo
 	/* xgettext:c-format */
 	(_("%pB(%pA+0x%v): relocation %s against `%s' must be used "
-	   "in indirect CALL only\n"),
-	 abfd, asect, rel->r_offset, from_reloc_name, name);
+	   "in indirect CALL with %s register only\n"),
+	 abfd, asect, rel->r_offset, from_reloc_name, name,
+	 htab->ax_register);
       break;
 
     case elf_x86_tls_error_lea:

bfd/elfxx-x86.h

@@ -687,6 +687,7 @@ struct elf_x86_link_hash_table
   const char *dynamic_interpreter;
   const char *tls_get_addr;
   const char *relative_r_name;
+  const char *ax_register;
   void (*elf_append_reloc) (bfd *, asection *, Elf_Internal_Rela *);
   void (*elf_write_addend) (bfd *, uint64_t, void *);
   void (*elf_write_addend_in_got) (bfd *, uint64_t, void *);

ld/testsuite/ld-i386/tlsgdesc2.d

@@ -1,4 +1,4 @@
 #name: TLS GDesc->LE transition check (indirect CALL)
 #as: --32
 #ld: -melf_i386
-#error: .*: relocation R_386_TLS_DESC_CALL against `foo' must be used in indirect CALL only
+#error: .*: relocation R_386_TLS_DESC_CALL against `foo' must be used in indirect CALL with EAX register only

ld/testsuite/ld-i386/tlsgdesc2.s

@@ -1,8 +1,8 @@
 	.text
 	.globl _start
 _start:
-	leal	foo@tlsdesc(%ebx), %eax
-	jmp	*foo@tlscall(%eax)
+	leal	foo@tlsdesc(%ebx), %ecx
+	call	*foo@tlscall(%ecx)
 	.section	.tdata,"awT",@progbits
 	.align 4
 	.type	foo, @object

ld/testsuite/ld-x86-64/tlsdesc4.d

@@ -1,4 +1,4 @@
 #name: TLS GDesc->LE transition check (indirect CALL)
 #as: --64
 #ld: -melf_x86_64
-#error: .*: relocation R_X86_64_TLSDESC_CALL against `foo' must be used in indirect CALL only
+#error: .*: relocation R_X86_64_TLSDESC_CALL against `foo' must be used in indirect CALL with RAX register only

ld/testsuite/ld-x86-64/tlsdesc4.s

@@ -2,8 +2,8 @@
 	.globl	_start
 	.type	_start,@function
 _start:
-	leaq	foo@tlsdesc(%rip), %rax
-	jmp	*foo@tlscall(%rax)
+	leaq	foo@tlsdesc(%rip), %rcx
+	call	*foo@tlscall(%rcx)
 	.globl foo
 	.section	.tdata,"awT",@progbits
 	.align 8