Nios II CALL26 linker relaxation

2014-01-30  Sandra Loosemore  <sandra@codesourcery.com>

	bfd/
	* bfd-in2.h: Update from reloc.c.
	* elf32-nios2.c: Include elf32-nios2.h.
	(elf_nios2_howto_table_rel): Add entry for R_NIOS2_CALL26_NOAT.
	(nios2_reloc_map): Likewise.
	(enum elf32_nios2_stub_type): Declare.
	(struct elf32_nios2_stub_hash_entry): Declare.
	(nios2_stub_hash_entry, nios2_stub_hash_lookup): New macros.
	(struct elf32_nios2_link_hash_entry): Add hsh_cache field.
	(struct elf32_nios2_link_hash_table): Add new fields bstab,
	stub_bfd, add_stub_section, layout_sections_again, stub_group,
	bfd_count, top_index, input_list, all_local_syms.
	(nios2_call26_stub_entry): New.
	(nios2_elf32_install_imm16): Move up in file.
	(nios2_elf32_install_data): Move up in file.
	(hiadj): Move up in file.
	(stub_hash_newfunc): New.
	(link_hash_newfunc): Initialize hsh_cache field.
	(STUB_SUFFIX): New.
	(nios2_stub_name): New.
	(nios2_get_stub_entry): New.
	(nios2_add_stub): New.
	(nios2_elf32_setup_section_lists): New.
	(nios2_elf32_next_input_section): New.
	(CALL26_SEGMENT): New.
	(MAX_STUB_SECTION_SIZE): New.
	(group_sections): New.
	(nios2_type_of_stub): New.
	(nios2_build_one_stub): New.
	(nios2_size_one_stub): New.
	(get_local_syms): New.
	(nios2_elf32_size_stubs): New.
	(nios2_elf32_build_stubs): New.
	(nios2_elf32_do_call26_relocate): Correct CALL26 overflow test.
	(nios2_elf32_relocate_section): Handle R_NIOS2_CALL26_NOAT.  Add
	trampolines for R_NIOS2_CALL26 stubs.
	(nios2_elf32_check_relocs): Handle R_NIOS2_CALL26_NOAT.
	(nios2_elf32_gc_sweep_hook): Likewise.
	(nios2_elf32_link_hash_table_create): Initialize the stub hash table.
	(nios2_elf32_link_hash_table_free): New.
	(bfd_elf32_bfd_link_hash_table_free): Define.
	* elf32-nios2.h: New file.
	* libbfd.h: Update from reloc.c.
	* reloc.c (BFD_RELOC_NIOS2_CALL26_NOAT): New.

	gas/
	* config/tc-nios2.c (md_apply_fix): Handle BFD_RELOC_NIOS2_CALL26_NOAT.
	(nios2_assemble_args_m): Likewise.
	(md_assemble): Likewise.

	gas/testsuite/
	* gas/nios2/call26_noat.d: New.
	* gas/nios2/call26_noat.s: New.
	* gas/nios2/call_noat.d: New.
	* gas/nios2/call_noat.s: New.

	include/elf/
	* nios2.h (elf_nios2_reloc_type): Add R_NIOS2_CALL26_NOAT.

	ld/
	* Makefile.am (enios2elf.c, enios2linux.c): Update dependencies.
	* Makefile.in: Regenerated.
	* emulparams/nios2elf.sh (EXTRA_EM_FILE): Set.
	* emulparams/nios2linux.sh (EXTRA_EM_FILE): Set.
	* emultempl/nios2elf.em: New file.
	* gen-doc.texi (NIOSII): Set.
	* ld.texinfo (NIOSII): Set.

	ld/testsuite/
	* ld-nios2/relax_call26.s: New.
	* ld-nios2/relax_call26_boundary.ld: New.
	* ld-nios2/relax_call26_boundary.s: New.
	* ld-nios2/relax_call26_boundary_c8.d: New.
	* ld-nios2/relax_call26_boundary_cc.d: New.
	* ld-nios2/relax_call26_boundary_d0.d: New.
	* ld-nios2/relax_call26_boundary_d4.d: New.
	* ld-nios2/relax_call26_boundary_d8.d: New.
	* ld-nios2/relax_call26_boundary_dc.d: New.
	* ld-nios2/relax_call26_boundary_f0.d: New.
	* ld-nios2/relax_call26_boundary_f4.d: New.
	* ld-nios2/relax_call26_boundary_f8.d: New.
	* ld-nios2/relax_call26_boundary_fc.d: New.
	* ld-nios2/relax_call26_cache.d: New.
	* ld-nios2/relax_call26_cache.ld: New.
	* ld-nios2/relax_call26_cache.s: New.
	* ld-nios2/relax_call26_multi.d: New.
	* ld-nios2/relax_call26_multi.ld: New.
	* ld-nios2/relax_call26_norelax.d: New.
	* ld-nios2/relax_call26_shared.d: New.
	* ld-nios2/relax_call26_shared.ld: New.

21 files changed, 309 insertions, 0 deletions

diff --git a/ld/testsuite/ld-nios2/relax_call26.s b/ld/testsuite/ld-nios2/relax_call26.s
new file mode 100644
index 0000000..b3b28df
--- /dev/null
+++ b/ld/testsuite/ld-nios2/relax_call26.s
@@ -0,0 +1,27 @@
+# test for call26 relaxation via linker stubs
+
+.globl text0
+.section text0, "ax", @progbits
+	call func0	# in same section
+	call func1	# in nearby section
+	call func2a	# in distant section
+	jmpi func2b	# also in distant section
+
+func0:
+	ret
+
+.section text1, "ax", @progbits
+func1:
+	nop
+	nop
+	call func2a	# in distant section
+	ret
+
+.section text2, "ax", @progbits
+func2a:
+	nop
+	nop
+	nop
+	ret
+func2b:
+	nop
diff --git a/ld/testsuite/ld-nios2/relax_call26_boundary.ld b/ld/testsuite/ld-nios2/relax_call26_boundary.ld
new file mode 100644
index 0000000..313ef8c
--- /dev/null
+++ b/ld/testsuite/ld-nios2/relax_call26_boundary.ld
@@ -0,0 +1,14 @@
+/* Simple script for testing call26 relaxation via linker stubs.
+   This script is used for a bunch of tests that vary the placement of
+   section text0 near a 256 memory segment boundary, by using
+   --section-start command-line options.  */
+
+OUTPUT_FORMAT("elf32-littlenios2", "elf32-littlenios2", "elf32-littlenios2")
+OUTPUT_ARCH(nios2)
+ENTRY(_start)
+SECTIONS
+{
+	_start = .;
+	text0 : { *(text0) *(text1) }
+	text2 0x40000000 : { *(text2) }
+}
diff --git a/ld/testsuite/ld-nios2/relax_call26_boundary.s b/ld/testsuite/ld-nios2/relax_call26_boundary.s
new file mode 100644
index 0000000..ce79ebd
--- /dev/null
+++ b/ld/testsuite/ld-nios2/relax_call26_boundary.s
@@ -0,0 +1,29 @@
+# Test for call26 relaxation via linker stubs.
+# This .s file is used with several different linker scripts that vary the
+# placement of the sections in the output.
+# Section text0 is 32 bytes long and requires at least 2 linker stubs
+# (12 bytes each) to reach the call destinations in text2.  Another stub
+# may be required to reach func0 if the section is laid out so that it crosses 
+# a 256MB memory segment boundary.
+
+.globl text0
+.section text0, "ax", @progbits
+	call func0	# in same section
+	call func2a	# in distant section
+	nop
+	nop
+	nop
+	nop
+	jmpi func2b	# in distant section
+
+func0:
+	ret
+
+.section text2, "ax", @progbits
+func2a:
+	nop
+	nop
+	nop
+	ret
+func2b:
+	nop
diff --git a/ld/testsuite/ld-nios2/relax_call26_boundary_c8.d b/ld/testsuite/ld-nios2/relax_call26_boundary_c8.d
new file mode 100644
index 0000000..61fd858
--- /dev/null
+++ b/ld/testsuite/ld-nios2/relax_call26_boundary_c8.d
@@ -0,0 +1,9 @@
+#name: NIOS2 relax_call26_boundary_c8
+#ld: --relax -Trelax_call26_boundary.ld --section-start=text0=0x0fffffc8
+#source: relax_call26_boundary.s
+#objdump: -dr --prefix-addresses 
+# Test relaxation of call26 relocations via linker stubs.  We don't need to
+# check the exact layout of stubs for this test, only verify that it
+# links without "relocation truncated to fit" errors.
+
+#pass
diff --git a/ld/testsuite/ld-nios2/relax_call26_boundary_cc.d b/ld/testsuite/ld-nios2/relax_call26_boundary_cc.d
new file mode 100644
index 0000000..c3a571a
--- /dev/null
+++ b/ld/testsuite/ld-nios2/relax_call26_boundary_cc.d
@@ -0,0 +1,9 @@
+#name: NIOS2 relax_call26_boundary_cc
+#ld: --relax -Trelax_call26_boundary.ld --section-start=text0=0x0fffffcc
+#source: relax_call26_boundary.s
+#objdump: -dr --prefix-addresses 
+# Test relaxation of call26 relocations via linker stubs.  We don't need to
+# check the exact layout of stubs for this test, only verify that it
+# links without "relocation truncated to fit" errors.
+
+#pass
diff --git a/ld/testsuite/ld-nios2/relax_call26_boundary_d0.d b/ld/testsuite/ld-nios2/relax_call26_boundary_d0.d
new file mode 100644
index 0000000..67f28ce
--- /dev/null
+++ b/ld/testsuite/ld-nios2/relax_call26_boundary_d0.d
@@ -0,0 +1,9 @@
+#name: NIOS2 relax_call26_boundary_d0
+#ld: --relax -Trelax_call26_boundary.ld --section-start=text0=0x0fffffd0
+#source: relax_call26_boundary.s
+#objdump: -dr --prefix-addresses 
+# Test relaxation of call26 relocations via linker stubs.  We don't need to
+# check the exact layout of stubs for this test, only verify that it
+# links without "relocation truncated to fit" errors.
+
+#pass
diff --git a/ld/testsuite/ld-nios2/relax_call26_boundary_d4.d b/ld/testsuite/ld-nios2/relax_call26_boundary_d4.d
new file mode 100644
index 0000000..9ffdf0e
--- /dev/null
+++ b/ld/testsuite/ld-nios2/relax_call26_boundary_d4.d
@@ -0,0 +1,9 @@
+#name: NIOS2 relax_call26_boundary_d4
+#ld: --relax -Trelax_call26_boundary.ld --section-start=text0=0x0fffffd4
+#source: relax_call26_boundary.s
+#objdump: -dr --prefix-addresses 
+# Test relaxation of call26 relocations via linker stubs.  We don't need to
+# check the exact layout of stubs for this test, only verify that it
+# links without "relocation truncated to fit" errors.
+
+#pass
diff --git a/ld/testsuite/ld-nios2/relax_call26_boundary_d8.d b/ld/testsuite/ld-nios2/relax_call26_boundary_d8.d
new file mode 100644
index 0000000..168d532
--- /dev/null
+++ b/ld/testsuite/ld-nios2/relax_call26_boundary_d8.d
@@ -0,0 +1,9 @@
+#name: NIOS2 relax_call26_boundary_d8
+#ld: --relax -Trelax_call26_boundary.ld --section-start=text0=0x0fffffd8
+#source: relax_call26_boundary.s
+#objdump: -dr --prefix-addresses 
+# Test relaxation of call26 relocations via linker stubs.  We don't need to
+# check the exact layout of stubs for this test, only verify that it
+# links without "relocation truncated to fit" errors.
+
+#pass
diff --git a/ld/testsuite/ld-nios2/relax_call26_boundary_dc.d b/ld/testsuite/ld-nios2/relax_call26_boundary_dc.d
new file mode 100644
index 0000000..539051e
--- /dev/null
+++ b/ld/testsuite/ld-nios2/relax_call26_boundary_dc.d
@@ -0,0 +1,9 @@
+#name: NIOS2 relax_call26_boundary_dc
+#ld: --relax -Trelax_call26_boundary.ld --section-start=text0=0x0fffffdc
+#source: relax_call26_boundary.s
+#objdump: -dr --prefix-addresses 
+# Test relaxation of call26 relocations via linker stubs.  We don't need to
+# check the exact layout of stubs for this test, only verify that it
+# links without "relocation truncated to fit" errors.
+
+#pass
diff --git a/ld/testsuite/ld-nios2/relax_call26_boundary_f0.d b/ld/testsuite/ld-nios2/relax_call26_boundary_f0.d
new file mode 100644
index 0000000..fe83151
--- /dev/null
+++ b/ld/testsuite/ld-nios2/relax_call26_boundary_f0.d
@@ -0,0 +1,9 @@
+#name: NIOS2 relax_call26_boundary_f0
+#ld: --relax -Trelax_call26_boundary.ld --section-start=text0=0x0ffffff0
+#source: relax_call26_boundary.s
+#objdump: -dr --prefix-addresses 
+# Test relaxation of call26 relocations via linker stubs.  We don't need to
+# check the exact layout of stubs for this test, only verify that it
+# links without "relocation truncated to fit" errors.
+
+#pass
diff --git a/ld/testsuite/ld-nios2/relax_call26_boundary_f4.d b/ld/testsuite/ld-nios2/relax_call26_boundary_f4.d
new file mode 100644
index 0000000..4006ff2
--- /dev/null
+++ b/ld/testsuite/ld-nios2/relax_call26_boundary_f4.d
@@ -0,0 +1,9 @@
+#name: NIOS2 relax_call26_boundary_f4
+#ld: --relax -Trelax_call26_boundary.ld --section-start=text0=0x0ffffff4
+#source: relax_call26_boundary.s
+#objdump: -dr --prefix-addresses 
+# Test relaxation of call26 relocations via linker stubs.  We don't need to
+# check the exact layout of stubs for this test, only verify that it
+# links without "relocation truncated to fit" errors.
+
+#pass
diff --git a/ld/testsuite/ld-nios2/relax_call26_boundary_f8.d b/ld/testsuite/ld-nios2/relax_call26_boundary_f8.d
new file mode 100644
index 0000000..10eb654
--- /dev/null
+++ b/ld/testsuite/ld-nios2/relax_call26_boundary_f8.d
@@ -0,0 +1,9 @@
+#name: NIOS2 relax_call26_boundary_f8
+#ld: --relax -Trelax_call26_boundary.ld --section-start=text0=0x0ffffff8
+#source: relax_call26_boundary.s
+#objdump: -dr --prefix-addresses 
+# Test relaxation of call26 relocations via linker stubs.  We don't need to
+# check the exact layout of stubs for this test, only verify that it
+# links without "relocation truncated to fit" errors.
+
+#pass
diff --git a/ld/testsuite/ld-nios2/relax_call26_boundary_fc.d b/ld/testsuite/ld-nios2/relax_call26_boundary_fc.d
new file mode 100644
index 0000000..cf93b5a
--- /dev/null
+++ b/ld/testsuite/ld-nios2/relax_call26_boundary_fc.d
@@ -0,0 +1,9 @@
+#name: NIOS2 relax_call26_boundary_fc
+#ld: --relax -Trelax_call26_boundary.ld --section-start=text0=0x0ffffffc
+#source: relax_call26_boundary.s
+#objdump: -dr --prefix-addresses 
+# Test relaxation of call26 relocations via linker stubs.  We don't need to
+# check the exact layout of stubs for this test, only verify that it
+# links without "relocation truncated to fit" errors.
+
+#pass
diff --git a/ld/testsuite/ld-nios2/relax_call26_cache.d b/ld/testsuite/ld-nios2/relax_call26_cache.d
new file mode 100644
index 0000000..43121c0
--- /dev/null
+++ b/ld/testsuite/ld-nios2/relax_call26_cache.d
@@ -0,0 +1,9 @@
+#name: NIOS2 relax_call26_cache
+#ld: --relax -Trelax_call26_cache.ld
+#source: relax_call26_cache.s
+#objdump: -dr --prefix-addresses 
+# Test relaxation of call26 relocations via linker stubs.  We don't need to
+# check the exact layout of stubs for this test, only verify that it
+# links without "relocation truncated to fit" errors.
+
+#pass
diff --git a/ld/testsuite/ld-nios2/relax_call26_cache.ld b/ld/testsuite/ld-nios2/relax_call26_cache.ld
new file mode 100644
index 0000000..d3c4307
--- /dev/null
+++ b/ld/testsuite/ld-nios2/relax_call26_cache.ld
@@ -0,0 +1,13 @@
+/* Simple script for testing call26 relaxation via linker stubs.
+   In this case, input sections text0 and text1 are placed in the
+   same output section in the same 256MB segment, so they can share stubs.  */
+
+OUTPUT_FORMAT("elf32-littlenios2", "elf32-littlenios2", "elf32-littlenios2")
+OUTPUT_ARCH(nios2)
+ENTRY(_start)
+SECTIONS
+{
+	_start = .;
+	text0 0x0fffffe0 : { *(text0) *(text1) }
+	text2 0x40000000 : { *(text2) }
+}
diff --git a/ld/testsuite/ld-nios2/relax_call26_cache.s b/ld/testsuite/ld-nios2/relax_call26_cache.s
new file mode 100644
index 0000000..3712853
--- /dev/null
+++ b/ld/testsuite/ld-nios2/relax_call26_cache.s
@@ -0,0 +1,28 @@
+# test for call26 relaxation via linker stubs
+#
+# The purpose of this test is to ensure that, when section text0 straddles
+# a 256MB memory segment boundary with calls to the same function on either
+# side, the stub caching doesn't get confused and incorrectly use a stub
+# on the wrong side.
+
+.globl text0
+.section text0, "ax", @progbits
+	call func2a	# in distant section
+	call func2a	# in distant section
+	nop
+	nop
+	nop
+	nop
+	nop
+	nop
+	nop
+	nop
+	nop
+	nop
+	call func2a	# in distant section
+	call func2a	# in distant section
+
+.section text2, "ax", @progbits
+.globl func2a
+func2a:
+	ret
diff --git a/ld/testsuite/ld-nios2/relax_call26_multi.d b/ld/testsuite/ld-nios2/relax_call26_multi.d
new file mode 100644
index 0000000..28279ef
--- /dev/null
+++ b/ld/testsuite/ld-nios2/relax_call26_multi.d
@@ -0,0 +1,36 @@
+#name: NIOS2 relax_call26_multi
+#ld: --relax -Trelax_call26_multi.ld
+#source: relax_call26.s
+#objdump: -dr --prefix-addresses 
+# Test relaxation of call26 relocations via linker stubs
+
+.*: +file format elf32-littlenios2
+
+Disassembly of section text0:
+00000000 <_start> call	00000010 <func0>
+00000004 <[^>]*> call	0000002c <func1>
+00000008 <[^>]*> call	00000020 <[^>]*>
+0000000c <[^>]*> jmpi	00000014 <[^>]*>
+00000010 <func0> ret
+00000014 <[^>]*> movhi	at,16384
+00000018 <[^>]*> addi	at,at,16
+0000001c <[^>]*> jmp	at
+00000020 <[^>]*> movhi	at,16384
+00000024 <[^>]*> addi	at,at,0
+00000028 <[^>]*> jmp	at
+
+Disassembly of section text1:
+0000002c <func1> nop
+00000030 <[^>]*> nop
+00000034 <[^>]*> call	0000003c <[^>]*>
+00000038 <[^>]*> ret
+0000003c <[^>]*> movhi	at,16384
+00000040 <[^>]*> addi	at,at,0
+00000044 <[^>]*> jmp	at
+
+Disassembly of section text2:
+40000000 <func2a> nop
+40000004 <[^>]*> nop
+40000008 <[^>]*> nop
+4000000c <[^>]*> ret
+40000010 <func2b> nop
diff --git a/ld/testsuite/ld-nios2/relax_call26_multi.ld b/ld/testsuite/ld-nios2/relax_call26_multi.ld
new file mode 100644
index 0000000..750f747
--- /dev/null
+++ b/ld/testsuite/ld-nios2/relax_call26_multi.ld
@@ -0,0 +1,14 @@
+/* Simple script for testing call26 relaxation via linker stubs.
+   In this case, input sections text0 and text1 cannot share stubs
+   because they are in different output sections.  */
+
+OUTPUT_FORMAT("elf32-littlenios2", "elf32-littlenios2", "elf32-littlenios2")
+OUTPUT_ARCH(nios2)
+ENTRY(_start)
+SECTIONS
+{
+	_start = .;
+	text0 0 : { *(text0) }
+	text1 : { *(text1) }
+	text2 0x40000000 : { *(text2) }
+}
diff --git a/ld/testsuite/ld-nios2/relax_call26_norelax.d b/ld/testsuite/ld-nios2/relax_call26_norelax.d
new file mode 100644
index 0000000..7c7371c
--- /dev/null
+++ b/ld/testsuite/ld-nios2/relax_call26_norelax.d
@@ -0,0 +1,5 @@
+#name: NIOS2 relax_call26_norelax
+#ld: --no-relax -Trelax_call26_multi.ld
+#source: relax_call26.s
+#error: .*relocation truncated to fit: R_NIOS2_CALL26.*
+# Test relaxation of call26 relocations via linker stubs
diff --git a/ld/testsuite/ld-nios2/relax_call26_shared.d b/ld/testsuite/ld-nios2/relax_call26_shared.d
new file mode 100644
index 0000000..75ccbca
--- /dev/null
+++ b/ld/testsuite/ld-nios2/relax_call26_shared.d
@@ -0,0 +1,31 @@
+#name: NIOS2 relax_call26_shared
+#ld: --relax -Trelax_call26_shared.ld
+#source: relax_call26.s
+#objdump: -dr --prefix-addresses 
+# Test relaxation of call26 relocations via linker stubs
+
+.*: +file format elf32-littlenios2
+
+Disassembly of section text0:
+00000000 <_start> call	00000010 <func0>
+00000004 <[^>]*> call	00000014 <func1>
+00000008 <[^>]*> call	00000030 <[^>]*>
+0000000c <[^>]*> jmpi	00000024 <[^>]*>
+00000010 <func0> ret
+00000014 <func1> nop
+00000018 <[^>]*> nop
+0000001c <[^>]*> call	00000030 <[^>]*>
+00000020 <[^>]*> ret
+00000024 <[^>]*> movhi	at,16384
+00000028 <[^>]*> addi	at,at,16
+0000002c <[^>]*> jmp	at
+00000030 <[^>]*> movhi	at,16384
+00000034 <[^>]*> addi	at,at,0
+00000038 <[^>]*> jmp	at
+
+Disassembly of section text2:
+40000000 <func2a> nop
+40000004 <[^>]*> nop
+40000008 <[^>]*> nop
+4000000c <[^>]*> ret
+40000010 <func2b> nop
diff --git a/ld/testsuite/ld-nios2/relax_call26_shared.ld b/ld/testsuite/ld-nios2/relax_call26_shared.ld
new file mode 100644
index 0000000..6e6fd44
--- /dev/null
+++ b/ld/testsuite/ld-nios2/relax_call26_shared.ld
@@ -0,0 +1,13 @@
+/* Simple script for testing call26 relaxation via linker stubs.
+   In this case, input sections text0 and text1 are placed in the
+   same output section in the same 256MB segment, so they can share stubs.  */
+
+OUTPUT_FORMAT("elf32-littlenios2", "elf32-littlenios2", "elf32-littlenios2")
+OUTPUT_ARCH(nios2)
+ENTRY(_start)
+SECTIONS
+{
+	_start = .;
+	text0 0 : { *(text0) *(text1) }
+	text2 0x40000000 : { *(text2) }
+}