[binutils-gdb/binutils-2_25-branch] [AArch64] Backport fix for minimum code section alignment

[Jiong Wang]

https://sourceware.org/git/gitweb.cgi?p=binutils-gdb.git;h=07c58460aa93cf08f63383decf5bc4f2a02de5bf

commit 07c58460aa93cf08f63383decf5bc4f2a02de5bf
Author: Matthew Wahab <matthew.wahab@arm.com>
Date:   Thu Jun 4 11:16:56 2015 +0100

    [AArch64] Backport fix for minimum code section alignment

Diff:
---
 gas/ChangeLog                         |  5 +++++
 gas/config/tc-aarch64.c               |  9 ++++++++-
 gas/testsuite/ChangeLog               |  5 +++++
 gas/testsuite/gas/aarch64/codealign.d | 16 ++++++++++++++++
 gas/testsuite/gas/aarch64/codealign.s |  2 ++
 5 files changed, 36 insertions(+), 1 deletion(-)

diff --git a/gas/ChangeLog b/gas/ChangeLog
index 7632ef8..1195d98 100644
--- a/gas/ChangeLog
+++ b/gas/ChangeLog
@@ -1,3 +1,8 @@
+2015-06-04  Matthew Wahab  <matthew.wahab@arm.com>
+
+	* config/tc-aarch64.c (mapping_state): Set minimum alignment for code
+	sections.
+
 2015-05-07  Renlin Li  <renlin.li@arm.com>
 
 	* config/tc-aarch64.c (s_aarch64_inst): Align frag during state
diff --git a/gas/config/tc-aarch64.c b/gas/config/tc-aarch64.c
index 62a1a3f..10b1b74 100644
--- a/gas/config/tc-aarch64.c
+++ b/gas/config/tc-aarch64.c
@@ -1481,7 +1481,14 @@ mapping_state (enum mstate state)
     /* The mapping symbol has already been emitted.
        There is nothing else to do.  */
     return;
-  else if (TRANSITION (MAP_UNDEFINED, MAP_DATA))
+
+  if (state == MAP_INSN)
+    /* AArch64 instructions require 4-byte alignment.  When emitting
+       instructions into any section, record the appropriate section
+       alignment.  */
+    record_alignment (now_seg, 2);
+
+  if (TRANSITION (MAP_UNDEFINED, MAP_DATA))
     /* This case will be evaluated later in the next else.  */
     return;
   else if (TRANSITION (MAP_UNDEFINED, MAP_INSN))
diff --git a/gas/testsuite/ChangeLog b/gas/testsuite/ChangeLog
index 01f74ca..6477054 100644
--- a/gas/testsuite/ChangeLog
+++ b/gas/testsuite/ChangeLog
@@ -1,3 +1,8 @@
+2015-06-04  Matthew Wahab  <matthew.wahab@arm.com>
+
+	* gas/aarch64/codealign.d: Add test for code section alignment.
+	* gas/aarch64/codealign.s: New file.
+
 2015-05-14  Peter Bergner  <bergner@vnet.ibm.com>
 
 	Applied from master.
diff --git a/gas/testsuite/gas/aarch64/codealign.d b/gas/testsuite/gas/aarch64/codealign.d
new file mode 100644
index 0000000..8e75c87
--- /dev/null
+++ b/gas/testsuite/gas/aarch64/codealign.d
@@ -0,0 +1,16 @@
+#objdump: --section-headers 
+# Minimum code alignment should be set.
+# This test is only valid on ELF based ports.
+#not-target: *-*-*coff *-*-pe *-*-wince *-*-*aout* *-*-netbsd *-*-riscix*
+
+.*: +file format.*aarch64.*
+
+Sections:
+Idx Name          Size      VMA               LMA               File off  Algn
+  0 \.text         .*  .*  .*  .*  2\*\*2
+                  .*CODE.*
+  1 \.data         .*  .*  .* .*  2\*\*0
+                  .*DATA.*
+  2 \.bss          .*  .*  .*  .*  2\*\*0
+.*
+
diff --git a/gas/testsuite/gas/aarch64/codealign.s b/gas/testsuite/gas/aarch64/codealign.s
new file mode 100644
index 0000000..b80a6d9
--- /dev/null
+++ b/gas/testsuite/gas/aarch64/codealign.s
@@ -0,0 +1,2 @@
+.text
+  nop