sframe: Allow input R_*_NONE relocations

"ld -r" generates R_*_NONE relocations in sframe section if input
relocations in sframe section are against discarded section.  Allow
input R_*_NONE relocations if there are more relocation entries than
SFrame entries, instead of assuming number of SFrame entries == number
of relocation entries.

bfd/

	PR ld/33127
	* elf-sframe.c (sframe_decoder_init_func_bfdinfo): Allow input
	R_*_NONE relocations if there are more relocation entries than
	SFrame entries.

ld/

	PR ld/33127
	* testsuite/ld-x86-64/sframe-reloc-2a.s: New file.
	* testsuite/ld-x86-64/sframe-reloc-2b.s: Likewise.
	* testsuite/ld-x86-64/x86-64.exp: Run PR ld/33127 tests.

Signed-off-by: H.J. Lu <hjl.tools@gmail.com>
(cherry picked from commit 5f9bf0cf71)

bfd/elf-sframe.c

@@ -120,7 +120,6 @@ sframe_decoder_init_func_bfdinfo (bfd *abfd,
   if ((sec->flags & SEC_LINKER_CREATED) && cookie->rels == NULL)
     return true;
 
-  BFD_ASSERT (cookie->rels + fde_count == cookie->relend);
   rel = cookie->rels;
   for (i = 0; i < fde_count; i++)
     {
@@ -132,6 +131,14 @@ sframe_decoder_init_func_bfdinfo (bfd *abfd,
       rel++;
     }
 
+  /* If there are more relocation entries, they must be R_*_NONE which
+     may be generated from relocations against discarded sections by
+     ld -r.  */
+  for (; rel < cookie->relend; rel++)
+   if (rel->r_info != 0)
+     break;
+  BFD_ASSERT (rel == cookie->relend);
+
   return true;
 }
 

ld/testsuite/ld-x86-64/sframe-reloc-2a.s

@@ -0,0 +1,7 @@
+	.section	sect, "axG", @progbits, sectgroup, comdat
+	.global	_start
+_start:
+	.cfi_startproc
+	call	foo
+	.cfi_endproc
+	.section	.note.GNU-stack,"",@progbits

ld/testsuite/ld-x86-64/sframe-reloc-2b.s

@@ -0,0 +1,31 @@
+	.section	sect, "axG", @progbits, sectgroup, comdat
+	.cfi_startproc
+# Test intention is that LSDA must be provided by the discarded FDE.
+# DW_EH_PE_udata8 = 4
+# DW_EH_PE_udata4 = 3
+	.ifdef		ELF64
+	.cfi_lsda 4, lsda
+	.else
+	.cfi_lsda 3, lsda
+	.endif
+	.skip 16
+	.cfi_endproc
+
+	.text
+	.globl	foo
+	.type	foo, @function
+foo:
+	.cfi_startproc
+	pushq	%rbp
+	.cfi_def_cfa_offset 16
+	.cfi_offset 6, -16
+	movq	%rsp, %rbp
+	.cfi_def_cfa_register 6
+	popq	%rbp
+	.cfi_def_cfa 7, 8
+	ret
+	.cfi_endproc
+
+	.section	.gcc_except_table, "a", @progbits
+lsda:
+	.section	.note.GNU-stack,"",@progbits

ld/testsuite/ld-x86-64/x86-64.exp

@@ -572,6 +572,27 @@ if { ![skip_sframe_tests] } {
     run_dump_test "sframe-ibt-plt-1"
     run_dump_test "sframe-pltgot-1"
     run_dump_test "sframe-pltgot-2"
+
+    run_ld_link_tests [list \
+	[list \
+	    "Build sframe-reloc-2.o" \
+	    "-m elf_x86_64 -r" \
+	    "" \
+	    "--64 --gsframe" \
+	    {sframe-reloc-2a.s sframe-reloc-2b.s} \
+	    "" \
+	    "sframe-reloc-2.o" \
+	] \
+	[list \
+	    "Build sframe-reloc-2" \
+	    "-m elf_x86_64 tmpdir/sframe-reloc-2.o" \
+	    "" \
+	    "--64 --gsframe" \
+	    {dummy.s} \
+	    "" \
+	    "sframe-reloc-2" \
+	] \
+    ]
 }
 
 if ![istarget "x86_64-*-linux*"] {