2016-08-04 Thomas Preud'homme <thomas.preudhomme@arm.com>

bfd/
	* elf32-arm.c (CMSE_PREFIX): Define macro.
	(elf32_arm_stub_cmse_branch_thumb_only): Define stub sequence.
	(cmse_branch_thumb_only): Declare stub.
	(struct elf32_arm_link_hash_table): Define cmse_stub_sec field.
	(elf32_arm_get_plt_info): Add globals parameter.  Use it to return
	FALSE if there is no PLT.
	(arm_type_of_stub): Adapt to new elf32_arm_get_plt_info signature.
	(elf32_arm_final_link_relocate): Likewise.
	(elf32_arm_gc_sweep_hook): Likewise.
	(elf32_arm_gc_mark_extra_sections): Mark sections holding ARMv8-M
	secure entry functions.
	(arm_stub_is_thumb): Add case for arm_stub_cmse_branch_thumb_only.
	(arm_dedicated_stub_output_section_required): Change to a switch case
	and add a case for arm_stub_cmse_branch_thumb_only.
	(arm_dedicated_stub_output_section_required_alignment): Likewise.
	(arm_stub_dedicated_output_section_name): Likewise.
	(arm_stub_dedicated_input_section_ptr): Likewise and remove
	ATTRIBUTE_UNUSED for htab parameter.
	(arm_stub_required_alignment): Likewise.
	(arm_stub_sym_claimed): Likewise.
	(arm_dedicated_stub_section_padding): Likewise.
	(cmse_scan): New function.
	(elf32_arm_size_stubs): Call cmse_scan for ARM M profile targets.
	Set stub_changed to TRUE if such veneers were created.
	(elf32_arm_swap_symbol_in): Add detection code for CMSE special
	symbols.

include/
	* arm.h (ARM_GET_SYM_CMSE_SPCL): Define macro.
	(ARM_SET_SYM_CMSE_SPCL): Likewise.

ld/
	* ld.texinfo (Placement of SG veneers): New concept entry.
	* testsuite/ld-arm/arm-elf.exp
	(Secure gateway veneers: no .gnu.sgstubs section): New test.
	(Secure gateway veneers: wrong entry functions): Likewise.
	(Secure gateway veneers (ARMv8-M Baseline)): Likewise.
	(Secure gateway veneers (ARMv8-M Mainline)): Likewise.
	* testsuite/ld-arm/cmse-veneers.s: New file.
	* testsuite/ld-arm/cmse-veneers.d: Likewise.
	* testsuite/ld-arm/cmse-veneers.rd: Likewise.
	* testsuite/ld-arm/cmse-veneers.sd: Likewise.
	* testsuite/ld-arm/cmse-veneers-no-gnu_sgstubs.out: Likewise.
	* testsuite/ld-arm/cmse-veneers-wrong-entryfct.out: Likewise.

9 files changed, 204 insertions, 0 deletions

diff --git a/ld/ChangeLog b/ld/ChangeLog
index 8dec408..49f7972 100644
--- a/ld/ChangeLog
+++ b/ld/ChangeLog
@@ -1,3 +1,18 @@
+2016-08-04  Thomas Preud'homme  <thomas.preudhomme@arm.com>
+
+	* ld.texinfo (Placement of SG veneers): New concept entry.
+	* testsuite/ld-arm/arm-elf.exp
+	(Secure gateway veneers: no .gnu.sgstubs section): New test.
+	(Secure gateway veneers: wrong entry functions): Likewise.
+	(Secure gateway veneers (ARMv8-M Baseline)): Likewise.
+	(Secure gateway veneers (ARMv8-M Mainline)): Likewise.
+	* testsuite/ld-arm/cmse-veneers.s: New file.
+	* testsuite/ld-arm/cmse-veneers.d: Likewise.
+	* testsuite/ld-arm/cmse-veneers.rd: Likewise.
+	* testsuite/ld-arm/cmse-veneers.sd: Likewise.
+	* testsuite/ld-arm/cmse-veneers-no-gnu_sgstubs.out: Likewise.
+	* testsuite/ld-arm/cmse-veneers-wrong-entryfct.out: Likewise.
+
 2016-08-02  Nick Clifton  <nickc@redhat.com>
 
 	PR ld/17739
diff --git a/ld/ld.texinfo b/ld/ld.texinfo
index b2dff10..af8cee3 100644
--- a/ld/ld.texinfo
+++ b/ld/ld.texinfo
@@ -6853,6 +6853,12 @@ entries which only support 512Mb of code.
 The @samp{--no-apply-dynamic-relocs} option makes AArch64 linker do not apply
 link-time values for dynamic relocations.
 
+@cindex Placement of SG veneers
+All SG veneers are placed in the special output section @code{.gnu.sgstubs}.
+Its start address must be set, either with the command line option
+@samp{--section-start} or in a linker script, to indicate where to place these
+veneers in memory.
+
 @ifclear GENERIC
 @lowersections
 @end ifclear
diff --git a/ld/testsuite/ld-arm/arm-elf.exp b/ld/testsuite/ld-arm/arm-elf.exp
index d0c9a2f..b3c8a84 100644
--- a/ld/testsuite/ld-arm/arm-elf.exp
+++ b/ld/testsuite/ld-arm/arm-elf.exp
@@ -642,6 +642,33 @@ set armeabitests_nonacl {
      {{objdump -d jump-reloc-veneers-long.d}}
      "jump-reloc-veneers-long"}
 
+    {"Secure gateway veneers: no .gnu.sgstubs section" "" ""
+     "-march=armv8-m.base -mthumb"
+     {cmse-veneers.s}
+     {{ld cmse-veneers-no-gnu_sgstubs.out}}
+     "cmse-veneers-no-gnu_sgstubs"}
+    {"Secure gateway veneers: wrong entry functions" "" ""
+     "-march=armv7-m -mthumb --defsym CHECK_ERRORS=1"
+     {cmse-veneers.s}
+     {{ld cmse-veneers-wrong-entryfct.out}}
+     "cmse-veneers-wrong-entryfct"}
+    {"Secure gateway veneers (ARMv8-M Baseline)"
+     "-Ttext=0x8000 --section-start .gnu.sgstubs=0x20000 --gc-sections" ""
+     "-march=armv8-m.base -mthumb"
+     {cmse-veneers.s}
+     {{objdump {-d -j .gnu.sgstubs} cmse-veneers.d}
+      {objdump {-h -j .gnu.sgstubs} cmse-veneers.sd}
+      {nm {} cmse-veneers.rd}}
+     "cmse-veneers-baseline"}
+    {"Secure gateway veneers (ARMv8-M Mainline)"
+     "-Ttext=0x8000 --section-start .gnu.sgstubs=0x20000 --gc-sections" ""
+     "-march=armv8-m.main -mthumb"
+     {cmse-veneers.s}
+     {{objdump {-d -j .gnu.sgstubs} cmse-veneers.d}
+      {objdump {-h -j .gnu.sgstubs} cmse-veneers.sd}
+      {nm {} cmse-veneers.rd}}
+     "cmse-veneers-mainline"}
+
     {"R_ARM_THM_JUMP19 Relocation veneers: Short"
      "--section-start destsect=0x000108002 --section-start .text=0x8000" ""
      "-march=armv7-m -mthumb"
diff --git a/ld/testsuite/ld-arm/cmse-veneers-no-gnu_sgstubs.out b/ld/testsuite/ld-arm/cmse-veneers-no-gnu_sgstubs.out
new file mode 100644
index 0000000..9d1e5ba
--- /dev/null
+++ b/ld/testsuite/ld-arm/cmse-veneers-no-gnu_sgstubs.out
@@ -0,0 +1,3 @@
+.*: No address assigned to the veneers output section .gnu.sgstubs
+.*: cannot size stub section: Invalid operation
+#...
diff --git a/ld/testsuite/ld-arm/cmse-veneers-wrong-entryfct.out b/ld/testsuite/ld-arm/cmse-veneers-wrong-entryfct.out
new file mode 100644
index 0000000..fd4766a
--- /dev/null
+++ b/ld/testsuite/ld-arm/cmse-veneers-wrong-entryfct.out
@@ -0,0 +1,19 @@
+.*: .*: Special symbol `__acle_se_loc_entry_veneer1' only allowed for ARMv8-M architecture or later.
+.*: .*: invalid .* symbol `.*loc_entry_veneer1'.
+.*: It must be a global or weak function symbol.
+.*: .*: invalid special symbol `__acle_se_loc_entry_veneer2'.
+.*: It must be a global or weak function symbol.
+.*: .*: invalid special symbol `__acle_se_loc_entry_veneer4'.
+.*: It must be a global or weak function symbol.
+.*: .*: invalid standard symbol `loc_entry_veneer3'.
+.*: It must be a global or weak function symbol.
+.*: .*: invalid standard symbol `loc_entry_veneer5'.
+.*: It must be a global or weak function symbol.
+.*: .*: absent standard symbol `fake_entry_veneer1'.
+.*: .*: invalid standard symbol `obj_entry_veneer1'.
+.*: It must be a global or weak function symbol.
+.*: .*: invalid special symbol `__acle_se_obj_entry_veneer2'.
+.*: It must be a global or weak function symbol.
+.*: .*: `fake_entry_veneer2' and its special symbol are in different sections.
+.*: cannot size stub section: Invalid operation
+#...
diff --git a/ld/testsuite/ld-arm/cmse-veneers.d b/ld/testsuite/ld-arm/cmse-veneers.d
new file mode 100644
index 0000000..6a44a2b
--- /dev/null
+++ b/ld/testsuite/ld-arm/cmse-veneers.d
@@ -0,0 +1,21 @@
+
+.*
+
+
+Disassembly of section \.gnu.sgstubs:
+
+00020000 <glob_entry_veneer2>:
+   20000:	e97f e97f 	sg
+   20004:	f7e8 b800 	b\.w	8008 <__acle_se_glob_entry_veneer2>
+
+00020008 <weak_entry_veneer2>:
+   20008:	e97f e97f 	sg
+   2000c:	f7e7 bffe 	b\.w	800c <__acle_se_weak_entry_veneer2>
+
+00020010 <glob_entry_veneer1>:
+   20010:	e97f e97f 	sg
+   20014:	f7e7 bff4 	b\.w	8000 <__acle_se_glob_entry_veneer1>
+
+00020018 <weak_entry_veneer1>:
+   20018:	e97f e97f 	sg
+   2001c:	f7e7 bff2 	b\.w	8004 <__acle_se_weak_entry_veneer1>
diff --git a/ld/testsuite/ld-arm/cmse-veneers.rd b/ld/testsuite/ld-arm/cmse-veneers.rd
new file mode 100644
index 0000000..20fad96
--- /dev/null
+++ b/ld/testsuite/ld-arm/cmse-veneers.rd
@@ -0,0 +1,9 @@
+#...
+[0-9a-f]+ T glob_entry_fct
+#...
+[0-9a-f]+ T glob_entry_veneer1
+[0-9a-f]+ T glob_entry_veneer2
+#...
+[0-9a-f]+ W weak_entry_veneer1
+[0-9a-f]+ W weak_entry_veneer2
+#...
diff --git a/ld/testsuite/ld-arm/cmse-veneers.s b/ld/testsuite/ld-arm/cmse-veneers.s
new file mode 100644
index 0000000..d5c57f6
--- /dev/null
+++ b/ld/testsuite/ld-arm/cmse-veneers.s
@@ -0,0 +1,97 @@
+	.syntax unified
+	.thumb
+	.file	"foo.c"
+	.text
+
+.macro	decltype	name, type
+.ifc \type,object
+	.data
+.else
+	.thumb
+	.thumb_func
+.endif
+	.type	\name, %\type
+.endm
+
+
+.macro	entry	name, type, vis, typespc, visspc, entry_fct
+	.align	2
+.ifb \visspc
+	.\vis	__acle_se_\name
+.else
+	.\visspc	__acle_se_\name
+.endif
+	.\vis	\name
+	.thumb
+	.thumb_func
+.ifb \typespc
+	decltype	__acle_se_\name, \type
+.else
+	decltype	__acle_se_\name, \typespc
+.endif
+	decltype	\name, \type
+__acle_se_\name:
+	\entry_fct
+\name:
+.ifc \type,object
+	.word 42
+.else
+	nop
+.endif
+	.size	\name, .-\name
+	.size	__acle_se_\name, .-__acle_se_\name
+.endm
+
+
+.ifndef CHECK_ERRORS
+	@ Valid setups for veneer generation
+	entry glob_entry_veneer1, function, global
+	entry weak_entry_veneer1, function, weak
+	entry glob_entry_veneer2, function, global, visspc=weak
+	entry weak_entry_veneer2, function, weak, visspc=global
+
+	@ Valid setup for entry function without SG veneer
+	entry glob_entry_fct, function, global, entry_fct=nop
+
+.else
+	@ Invalid setups for veneer generation (visibility)
+	entry loc_entry_veneer1, function, local
+	entry loc_entry_veneer2, function, global, visspc=local
+	entry loc_entry_veneer3, function, local, visspc=global
+	entry loc_entry_veneer4, function, weak, visspc=local
+	entry loc_entry_veneer5, function, local, visspc=weak
+
+	@ Invalid setups for veneer generation (absent standard symbol)
+	.align	2
+	.global	__acle_se_fake_entry_veneer1
+	.thumb
+	.thumb_func
+	.type	__acle_se_fake_entry_veneer1, %function
+__acle_se_fake_entry_veneer1:
+	nop
+	.size	__acle_se_fake_entry_veneer1, .-__acle_se_fake_entry_veneer1
+
+	@ Invalid setups for veneer generation (type)
+	entry obj_entry_veneer1, object, global, typespc=function
+	entry obj_entry_veneer2, function, global, typespc=object
+
+	@ Invalid setup for veneer generation (sections)
+	.section .text.sub1
+	.align	2
+	.thumb
+	.thumb_func
+	.global	__acle_se_fake_entry_veneer2
+	.type	__acle_se_fake_entry_veneer2, %function
+__acle_se_fake_entry_veneer2:
+	nop
+	.size	__acle_se_fake_entry_veneer2, .-__acle_se_fake_entry_veneer2
+	.section .text.sub2
+	.align	2
+	.thumb
+	.thumb_func
+	.global	fake_entry_veneer2
+	.type	fake_entry_veneer2, %function
+fake_entry_veneer2:
+	nop
+	.size	fake_entry_veneer2, .-fake_entry_veneer2
+.endif
diff --git a/ld/testsuite/ld-arm/cmse-veneers.sd b/ld/testsuite/ld-arm/cmse-veneers.sd
new file mode 100644
index 0000000..99bfc8f
--- /dev/null
+++ b/ld/testsuite/ld-arm/cmse-veneers.sd
@@ -0,0 +1,7 @@
+
+.*
+
+Sections:
+Idx Name          Size      VMA       LMA       File off  Algn
+  \d+ \.gnu\.sgstubs  00000020  00020000  00020000  00010000  2\*\*5
+                  CONTENTS, ALLOC, LOAD, READONLY, CODE