x86: Remove x86 ISA properties with empty bits

There is no need to generate x86 ISA properties with empty bits in
linker output.

bfd/

	PR ld/23372
	* elfxx-x86.c (_bfd_x86_elf_merge_gnu_properties): Remove x86
	ISA properties with empty bits.

ld/

	PR ld/23372
	* testsuite/ld-i386/i386.exp: Run pr23372a and pr23372b.
	* testsuite/ld-i386/pr23372a.d: New file.
	* testsuite/ld-i386/pr23372a.s: Likewise.
	* testsuite/ld-i386/pr23372b.d: Likewise.
	* testsuite/ld-i386/pr23372b.s: Likewise.
	* testsuite/ld-i386/pr23372c.s: Likewise.
	* testsuite/ld-x86-64/pr23372a-x32.d: Likewise.
	* testsuite/ld-x86-64/pr23372a.d: Likewise.
	* testsuite/ld-x86-64/pr23372a.s: Likewise.
	* testsuite/ld-x86-64/pr23372b-x32.d: Likewise.
	* testsuite/ld-x86-64/pr23372b.d: Likewise.
	* testsuite/ld-x86-64/pr23372b.s: Likewise.
	* testsuite/ld-x86-64/pr23372c.s: Likewise.
	* testsuite/ld-x86-64/x86-64.exp: Run pr23372a, pr23372a-x32,
	pr23372b and pr23372b-x32.

(cherry picked from commit 56ad703d56ffe5dc55d5e719a6ec41fd6cf9bfbe)

17 files changed, 230 insertions, 4 deletions

diff --git a/bfd/ChangeLog b/bfd/ChangeLog
index 41fa889..5abfc0d 100644
--- a/bfd/ChangeLog
+++ b/bfd/ChangeLog
@@ -1,3 +1,9 @@
+2018-07-09  H.J. Lu  <hongjiu.lu@intel.com>
+
+	PR ld/23372
+	* elfxx-x86.c (_bfd_x86_elf_merge_gnu_properties): Remove x86
+	ISA properties with empty bits.
+
 2018-07-06  Alan Modra  <amodra@gmail.com>
 
 	* elf32-arm.c (elf32_arm_nabi_write_core_note): Don't use
diff --git a/bfd/elfxx-x86.c b/bfd/elfxx-x86.c
index 827bb6c..a2497aa 100644
--- a/bfd/elfxx-x86.c
+++ b/bfd/elfxx-x86.c
@@ -2412,13 +2412,34 @@ _bfd_x86_elf_merge_gnu_properties (struct bfd_link_info *info,
 	{
 	  number = aprop->u.number;
 	  aprop->u.number = number | bprop->u.number;
-	  updated = number != (unsigned int) aprop->u.number;
+	  /* Remove the property if ISA bits are empty.  */
+	  if (aprop->u.number == 0)
+	    {
+	      aprop->pr_kind = property_remove;
+	      updated = TRUE;
+	    }
+	  else
+	    updated = number != (unsigned int) aprop->u.number;
 	}
       else
 	{
-	  /* Return TRUE if APROP is NULL to indicate that BPROP should
-	     be added to ABFD.  */
-	  updated = aprop == NULL;
+	  /* Only one of APROP and BPROP can be NULL.  */
+	  if (aprop != NULL)
+	    {
+	      if (aprop->u.number == 0)
+		{
+		  /* Remove APROP if ISA bits are empty.  */
+		  aprop->pr_kind = property_remove;
+		  updated = TRUE;
+		}
+	    }
+	  else
+	    {
+	      /* Return TRUE if APROP is NULL and ISA bits of BPROP
+		 aren't empty to indicate that BPROP should be added
+		 to ABFD.  */
+	      updated = bprop->u.number != 0;
+	    }
 	}
       break;
 
diff --git a/ld/ChangeLog b/ld/ChangeLog
index 0825f12..d165fa3 100644
--- a/ld/ChangeLog
+++ b/ld/ChangeLog
@@ -1,3 +1,22 @@
+2018-07-09  H.J. Lu  <hongjiu.lu@intel.com>
+
+	PR ld/23372
+	* testsuite/ld-i386/i386.exp: Run pr23372a and pr23372b.
+	* testsuite/ld-i386/pr23372a.d: New file.
+	* testsuite/ld-i386/pr23372a.s: Likewise.
+	* testsuite/ld-i386/pr23372b.d: Likewise.
+	* testsuite/ld-i386/pr23372b.s: Likewise.
+	* testsuite/ld-i386/pr23372c.s: Likewise.
+	* testsuite/ld-x86-64/pr23372a-x32.d: Likewise.
+	* testsuite/ld-x86-64/pr23372a.d: Likewise.
+	* testsuite/ld-x86-64/pr23372a.s: Likewise.
+	* testsuite/ld-x86-64/pr23372b-x32.d: Likewise.
+	* testsuite/ld-x86-64/pr23372b.d: Likewise.
+	* testsuite/ld-x86-64/pr23372b.s: Likewise.
+	* testsuite/ld-x86-64/pr23372c.s: Likewise.
+	* testsuite/ld-x86-64/x86-64.exp: Run pr23372a, pr23372a-x32,
+	pr23372b and pr23372b-x32.
+
 2018-07-05  Jim Wilson  <jimw@sifive.com>
 
 	* configure.tgt (riscv-*-*): Add as an alias for riscv32*-*-*.
diff --git a/ld/testsuite/ld-i386/i386.exp b/ld/testsuite/ld-i386/i386.exp
index bb91a76..6d794fe 100644
--- a/ld/testsuite/ld-i386/i386.exp
+++ b/ld/testsuite/ld-i386/i386.exp
@@ -460,6 +460,8 @@ run_dump_test "pr22782"
 run_dump_test "pr22929"
 run_dump_test "pr23189"
 run_dump_test "pr23194"
+run_dump_test "pr23372a"
+run_dump_test "pr23372b"
 
 if { !([istarget "i?86-*-linux*"]
        || [istarget "i?86-*-gnu*"]
diff --git a/ld/testsuite/ld-i386/pr23372a.d b/ld/testsuite/ld-i386/pr23372a.d
new file mode 100644
index 0000000..b75523b
--- /dev/null
+++ b/ld/testsuite/ld-i386/pr23372a.d
@@ -0,0 +1,5 @@
+#source: pr23372a.s
+#source: pr23372b.s
+#as: --32
+#ld: -r -m elf_i386
+#readelf: -n
diff --git a/ld/testsuite/ld-i386/pr23372a.s b/ld/testsuite/ld-i386/pr23372a.s
new file mode 100644
index 0000000..9849d62
--- /dev/null
+++ b/ld/testsuite/ld-i386/pr23372a.s
@@ -0,0 +1,18 @@
+	.section ".note.gnu.property", "a"
+	.p2align 2
+	.long 1f - 0f		/* name length.  */
+	.long 4f - 1f		/* data length.  */
+	/* NT_GNU_PROPERTY_TYPE_0 */
+	.long 5			/* note type.  */
+0:
+	.asciz "GNU"		/* vendor name.  */
+1:
+	.p2align 2
+	/* GNU_PROPERTY_X86_ISA_1_USED */
+	.long 0xc0000000	/* pr_type.  */
+	.long 3f - 2f		/* pr_datasz.  */
+2:
+	.long 0x0
+3:
+	.p2align 2
+4:
diff --git a/ld/testsuite/ld-i386/pr23372b.d b/ld/testsuite/ld-i386/pr23372b.d
new file mode 100644
index 0000000..a8e9c81
--- /dev/null
+++ b/ld/testsuite/ld-i386/pr23372b.d
@@ -0,0 +1,5 @@
+#source: pr23372a.s
+#source: pr23372c.s
+#as: --32
+#ld: -r -m elf_i386
+#readelf: -n
diff --git a/ld/testsuite/ld-i386/pr23372b.s b/ld/testsuite/ld-i386/pr23372b.s
new file mode 100644
index 0000000..9849d62
--- /dev/null
+++ b/ld/testsuite/ld-i386/pr23372b.s
@@ -0,0 +1,18 @@
+	.section ".note.gnu.property", "a"
+	.p2align 2
+	.long 1f - 0f		/* name length.  */
+	.long 4f - 1f		/* data length.  */
+	/* NT_GNU_PROPERTY_TYPE_0 */
+	.long 5			/* note type.  */
+0:
+	.asciz "GNU"		/* vendor name.  */
+1:
+	.p2align 2
+	/* GNU_PROPERTY_X86_ISA_1_USED */
+	.long 0xc0000000	/* pr_type.  */
+	.long 3f - 2f		/* pr_datasz.  */
+2:
+	.long 0x0
+3:
+	.p2align 2
+4:
diff --git a/ld/testsuite/ld-i386/pr23372c.s b/ld/testsuite/ld-i386/pr23372c.s
new file mode 100644
index 0000000..3470dce
--- /dev/null
+++ b/ld/testsuite/ld-i386/pr23372c.s
@@ -0,0 +1,18 @@
+	.section ".note.gnu.property", "a"
+	.p2align 2
+	.long 1f - 0f		/* name length.  */
+	.long 4f - 1f		/* data length.  */
+	/* NT_GNU_PROPERTY_TYPE_0 */
+	.long 5			/* note type.  */
+0:
+	.asciz "GNU"		/* vendor name.  */
+1:
+	.p2align 2
+	/* GNU_PROPERTY_X86_ISA_1_NEEDED */
+	.long 0xc0000001	/* pr_type.  */
+	.long 3f - 2f		/* pr_datasz.  */
+2:
+	.long 0x0
+3:
+	.p2align 2
+4:
diff --git a/ld/testsuite/ld-x86-64/pr23372a-x32.d b/ld/testsuite/ld-x86-64/pr23372a-x32.d
new file mode 100644
index 0000000..9f93642
--- /dev/null
+++ b/ld/testsuite/ld-x86-64/pr23372a-x32.d
@@ -0,0 +1,5 @@
+#source: pr23372a.s
+#source: pr23372b.s
+#as: --x32
+#ld: -r -m elf32_x86_64
+#readelf: -n
diff --git a/ld/testsuite/ld-x86-64/pr23372a.d b/ld/testsuite/ld-x86-64/pr23372a.d
new file mode 100644
index 0000000..ee688fc
--- /dev/null
+++ b/ld/testsuite/ld-x86-64/pr23372a.d
@@ -0,0 +1,5 @@
+#source: pr23372a.s
+#source: pr23372b.s
+#as: --64 -defsym __64_bit__=1
+#ld: -r -m elf_x86_64
+#readelf: -n
diff --git a/ld/testsuite/ld-x86-64/pr23372a.s b/ld/testsuite/ld-x86-64/pr23372a.s
new file mode 100644
index 0000000..639fc26
--- /dev/null
+++ b/ld/testsuite/ld-x86-64/pr23372a.s
@@ -0,0 +1,30 @@
+	.section ".note.gnu.property", "a"
+.ifdef __64_bit__
+	.p2align 3
+.else
+	.p2align 2
+.endif
+	.long 1f - 0f		/* name length.  */
+	.long 4f - 1f		/* data length.  */
+	/* NT_GNU_PROPERTY_TYPE_0 */
+	.long 5			/* note type.  */
+0:
+	.asciz "GNU"		/* vendor name.  */
+1:
+.ifdef __64_bit__
+	.p2align 3
+.else
+	.p2align 2
+.endif
+	/* GNU_PROPERTY_X86_ISA_1_USED */
+	.long 0xc0000000	/* pr_type.  */
+	.long 3f - 2f		/* pr_datasz.  */
+2:
+	.long 0x0
+3:
+.ifdef __64_bit__
+	.p2align 3
+.else
+	.p2align 2
+.endif
+4:
diff --git a/ld/testsuite/ld-x86-64/pr23372b-x32.d b/ld/testsuite/ld-x86-64/pr23372b-x32.d
new file mode 100644
index 0000000..5b0cf98
--- /dev/null
+++ b/ld/testsuite/ld-x86-64/pr23372b-x32.d
@@ -0,0 +1,5 @@
+#source: pr23372a.s
+#source: pr23372c.s
+#as: --x32
+#ld: -r -m elf32_x86_64
+#readelf: -n
diff --git a/ld/testsuite/ld-x86-64/pr23372b.d b/ld/testsuite/ld-x86-64/pr23372b.d
new file mode 100644
index 0000000..727afa8
--- /dev/null
+++ b/ld/testsuite/ld-x86-64/pr23372b.d
@@ -0,0 +1,5 @@
+#source: pr23372a.s
+#source: pr23372c.s
+#as: --64 -defsym __64_bit__=1
+#ld: -r -m elf_x86_64
+#readelf: -n
diff --git a/ld/testsuite/ld-x86-64/pr23372b.s b/ld/testsuite/ld-x86-64/pr23372b.s
new file mode 100644
index 0000000..639fc26
--- /dev/null
+++ b/ld/testsuite/ld-x86-64/pr23372b.s
@@ -0,0 +1,30 @@
+	.section ".note.gnu.property", "a"
+.ifdef __64_bit__
+	.p2align 3
+.else
+	.p2align 2
+.endif
+	.long 1f - 0f		/* name length.  */
+	.long 4f - 1f		/* data length.  */
+	/* NT_GNU_PROPERTY_TYPE_0 */
+	.long 5			/* note type.  */
+0:
+	.asciz "GNU"		/* vendor name.  */
+1:
+.ifdef __64_bit__
+	.p2align 3
+.else
+	.p2align 2
+.endif
+	/* GNU_PROPERTY_X86_ISA_1_USED */
+	.long 0xc0000000	/* pr_type.  */
+	.long 3f - 2f		/* pr_datasz.  */
+2:
+	.long 0x0
+3:
+.ifdef __64_bit__
+	.p2align 3
+.else
+	.p2align 2
+.endif
+4:
diff --git a/ld/testsuite/ld-x86-64/pr23372c.s b/ld/testsuite/ld-x86-64/pr23372c.s
new file mode 100644
index 0000000..b4eaf69
--- /dev/null
+++ b/ld/testsuite/ld-x86-64/pr23372c.s
@@ -0,0 +1,30 @@
+	.section ".note.gnu.property", "a"
+.ifdef __64_bit__
+	.p2align 3
+.else
+	.p2align 2
+.endif
+	.long 1f - 0f		/* name length.  */
+	.long 4f - 1f		/* data length.  */
+	/* NT_GNU_PROPERTY_TYPE_0 */
+	.long 5			/* note type.  */
+0:
+	.asciz "GNU"		/* vendor name.  */
+1:
+.ifdef __64_bit__
+	.p2align 3
+.else
+	.p2align 2
+.endif
+	/* GNU_PROPERTY_X86_ISA_1_NEEDED */
+	.long 0xc0000001	/* pr_type.  */
+	.long 3f - 2f		/* pr_datasz.  */
+2:
+	.long 0x0
+3:
+.ifdef __64_bit__
+	.p2align 3
+.else
+	.p2align 2
+.endif
+4:
diff --git a/ld/testsuite/ld-x86-64/x86-64.exp b/ld/testsuite/ld-x86-64/x86-64.exp
index e6ec049..6edb9e8 100644
--- a/ld/testsuite/ld-x86-64/x86-64.exp
+++ b/ld/testsuite/ld-x86-64/x86-64.exp
@@ -399,6 +399,10 @@ run_dump_test "pr23189"
 run_dump_test "pr23194"
 run_dump_test "pr23324a"
 run_dump_test "pr23324b"
+run_dump_test "pr23372a"
+run_dump_test "pr23372a-x32"
+run_dump_test "pr23372b"
+run_dump_test "pr23372b-x32"
 
 if { ![istarget "x86_64-*-linux*"] && ![istarget "x86_64-*-nacl*"]} {
     return