gold: Get alignment of uncompressed section from ch_addralign

The ELF compression header has a field (ch_addralign) that is set to
the alignment of the uncompressed section. This way the section itself
can have a different alignment than the decompressed section.  Update
decompress_input_section to get alignment of the decompressed section
and use it when merging decompressed strings.

	PR binutils/23919
	* merge.cc (Output_merge_string<Char_type>::do_add_input_section):
	Get addralign from decompressed_section_contents.
	* object.cc (build_compressed_section_map): Set info.addralign.
	(Object::decompressed_section_contents): Add a palign
	argument and store p->second.addralign in *palign if it isn't
	NULL.
	* object.h (Compressed_section_info): Add addralign.
	(section_is_compressed): Add a palign argument, default it
	to NULL, store p->second.addralign in *palign if it isn't NULL.
	(Object::decompressed_section_contents): Likewise.
	* output.cc (Output_section::add_input_section): Get addralign
	from section_is_compressed.

1 files changed, 5 insertions, 3 deletions

diff --git a/gold/merge.cc b/gold/merge.cc
index de00ee9..d7de117 100644
--- a/gold/merge.cc
+++ b/gold/merge.cc
@@ -440,9 +440,11 @@ Output_merge_string<Char_type>::do_add_input_section(Relobj* object,
 {
   section_size_type sec_len;
   bool is_new;
+  uint64_t addralign = this->addralign();
   const unsigned char* pdata = object->decompressed_section_contents(shndx,
 								     &sec_len,
-								     &is_new);
+								     &is_new,
+								     &addralign);
 
   const Char_type* p = reinterpret_cast<const Char_type*>(pdata);
   const Char_type* pend = p + sec_len / sizeof(Char_type);
@@ -494,7 +496,7 @@ Output_merge_string<Char_type>::do_add_input_section(Relobj* object,
   // aligned, so each string within the section must retain the same
   // modulo.
   uintptr_t init_align_modulo = (reinterpret_cast<uintptr_t>(pdata)
-				 & (this->addralign() - 1));
+				 & (addralign - 1));
   bool has_misaligned_strings = false;
 
   while (p < pend)
@@ -503,7 +505,7 @@ Output_merge_string<Char_type>::do_add_input_section(Relobj* object,
 
       // Within merge input section each string must be aligned.
       if (len != 0
-	  && ((reinterpret_cast<uintptr_t>(p) & (this->addralign() - 1))
+	  && ((reinterpret_cast<uintptr_t>(p) & (addralign - 1))
 	      != init_align_modulo))
 	  has_misaligned_strings = true;