Allocate the first .plt entry space only if needed

Commit dd7e64d45b317128f5fe813a8da0b13b4ad046ae may optimize out
i386/x86-64 JUMP_SLOT relocation.  If there is no JUMP_SLOT relocation
left, we don't need to the first .plt entry.  This patch allocates
space for the first .plt entry only if we also reserve space for a PLT
slot for JUMP_SLOT relocation.

bfd/

	* elf32-i386.c (elf_i386_allocate_dynrelocs): Allocate space
	for the first .plt entry only if needed.
	* elf64-x86-64.c (elf_x86_64_allocate_dynrelocs): Likewise.

ld/testsuite/

	* ld-i386/i386.exp: Run pltgot-1 for Linux targets.
	* ld-x86-64/x86-64.exp: Likewise.
	* ld-i386/pltgot-1.d: New file.
	* ld-i386/pltgot-1.s: Likewise.
	* ld-x86-64/pltgot-1.d: Likewise.
	* ld-x86-64/pltgot-1.s: Likewise.

7 files changed, 46 insertions, 0 deletions

diff --git a/ld/testsuite/ChangeLog b/ld/testsuite/ChangeLog
index 89f695c..f7bd9b7 100644
--- a/ld/testsuite/ChangeLog
+++ b/ld/testsuite/ChangeLog
@@ -1,3 +1,12 @@
+2015-05-12  H.J. Lu  <hongjiu.lu@intel.com>
+
+	* ld-i386/i386.exp: Run pltgot-1 for Linux targets.
+	* ld-x86-64/x86-64.exp: Likewise.
+	* ld-i386/pltgot-1.d: New file.
+	* ld-i386/pltgot-1.s: Likewise.
+	* ld-x86-64/pltgot-1.d: Likewise.
+	* ld-x86-64/pltgot-1.s: Likewise.
+
 2015-05-11  H.J. Lu  <hongjiu.lu@intel.com>
 
 	* ld-i386/i386.exp (iamcu_tests): Run iamcu-4.
diff --git a/ld/testsuite/ld-i386/i386.exp b/ld/testsuite/ld-i386/i386.exp
index 2e59522..bbc6005 100644
--- a/ld/testsuite/ld-i386/i386.exp
+++ b/ld/testsuite/ld-i386/i386.exp
@@ -493,3 +493,11 @@ if { [isnative]
 	] \
     ]
 }
+
+if { !([istarget "i?86-*-linux*"]
+       || [istarget "x86_64-*-linux*"]) } {
+    return
+}
+
+# Linux only tests
+run_dump_test "pltgot-1"
diff --git a/ld/testsuite/ld-i386/pltgot-1.d b/ld/testsuite/ld-i386/pltgot-1.d
new file mode 100644
index 0000000..6629635
--- /dev/null
+++ b/ld/testsuite/ld-i386/pltgot-1.d
@@ -0,0 +1,8 @@
+#ld: -shared -melf_i386
+#readelf: -S --wide
+#as: --32
+
+#failif
+#...
+ +\[ [0-9]+\] \.plt +PROGBITS +.*
+#...
diff --git a/ld/testsuite/ld-i386/pltgot-1.s b/ld/testsuite/ld-i386/pltgot-1.s
new file mode 100644
index 0000000..0e23078
--- /dev/null
+++ b/ld/testsuite/ld-i386/pltgot-1.s
@@ -0,0 +1,6 @@
+	.text
+	.globl	plt	
+	.type	plt, @function
+plt:
+	call   *puts@GOT(%ebx)
+	jmp	puts@PLT
diff --git a/ld/testsuite/ld-x86-64/pltgot-1.d b/ld/testsuite/ld-x86-64/pltgot-1.d
new file mode 100644
index 0000000..9a6c2fd6
--- /dev/null
+++ b/ld/testsuite/ld-x86-64/pltgot-1.d
@@ -0,0 +1,8 @@
+#ld: -shared -melf_x86_64
+#readelf: -S --wide
+#as: --64
+
+#failif
+#...
+ +\[ [0-9]+\] \.plt +PROGBITS +.*
+#...
diff --git a/ld/testsuite/ld-x86-64/pltgot-1.s b/ld/testsuite/ld-x86-64/pltgot-1.s
new file mode 100644
index 0000000..2197c75
--- /dev/null
+++ b/ld/testsuite/ld-x86-64/pltgot-1.s
@@ -0,0 +1,6 @@
+	.text
+	.globl	plt	
+	.type	plt, @function
+plt:
+	call   *puts@GOTPCREL(%rip)
+	jmp	puts@PLT
diff --git a/ld/testsuite/ld-x86-64/x86-64.exp b/ld/testsuite/ld-x86-64/x86-64.exp
index 8352ad9..58e598e 100644
--- a/ld/testsuite/ld-x86-64/x86-64.exp
+++ b/ld/testsuite/ld-x86-64/x86-64.exp
@@ -549,3 +549,4 @@ if { ![istarget "x86_64-*-linux*"]} {
 
 # Linux only tests
 run_dump_test "pr17618"
+run_dump_test "pltgot-1"