From 7d81bc937cd3949fc3bed8194646d3a4563f94b2 Mon Sep 17 00:00:00 2001 From: Jozef Lawrynowicz Date: Tue, 8 Sep 2020 16:13:48 +0100 Subject: MSP430: Support relocations for subtract expressions in .uleb128 directives Link-time relaxations of branches are common for MSP430, given that GCC can generate pessimal branch instructions, and the -mcode-region=either/-mdata-region=either options to shuffle sections can further change the type of branch instruction required. These relaxations can result in invalid code when .uleb128 directives, used in the .gcc_except_table section, are used to calculate the distance between two labels. A value for the .uleb128 directive is calculated at assembly-time, and can't be updated at link-time, even if relaxation causes the distance between the labels to change. This patch adds relocations for subtract expressions in .uleb128 directives, to allow the linker to re-calculate the value of these expressions after relaxation has been performed. bfd/ChangeLog: * bfd-in2.h (bfd_reloc_code_real): Add BFD_RELOC_MSP430_{SET,SUB}_ULEB128. * elf32-msp430.c (msp430_elf_ignore_reloc): New. (elf_msp430_howto_table): Add R_MSP430{,X}_GNU_{SET,SUB}_ULEB128. (msp430_reloc_map): Add R_MSP430_GNU_{SET,SUB}_ULEB128. (msp430x_reloc_map): Add R_MSP430X_GNU_{SET,SUB}_ULEB128. (write_uleb128): New. (msp430_final_link_relocate): Handle R_MSP430{,X}_GNU_{SET,SUB}_ULEB128. * libbfd.c (_bfd_write_unsigned_leb128): New. * libbfd.h (_bfd_write_unsigned_leb128): New prototype. Add BFD_RELOC_MSP430_{SET,SUB}_ULEB128. * reloc.c: Document BFD_RELOC_MSP430_{SET,SUB}_ULEB128. binutils/ChangeLog: * readelf.c (target_specific_reloc_handling): Handle R_MSP430{,X}_GNU_{SET,SUB}_ULEB128. gas/ChangeLog: * config/tc-msp430.c (msp430_insert_uleb128_fixes): New. (msp430_md_end): Call msp430_insert_uleb128_fixes. include/ChangeLog: * elf/msp430.h (elf_msp430_reloc_type): Add R_MSP430_GNU_{SET,SUB}_ULEB128. (elf_msp430x_reloc_type): Add R_MSP430X_GNU_{SET,SUB}_ULEB128. ld/ChangeLog: * testsuite/ld-msp430-elf/msp430-elf.exp: Run new tests. * testsuite/ld-msp430-elf/uleb128.s: New test. * testsuite/ld-msp430-elf/uleb128_430.d: New test. * testsuite/ld-msp430-elf/uleb128_430x.d: New test. --- ld/ChangeLog | 7 +++++++ 1 file changed, 7 insertions(+) (limited to 'ld/ChangeLog') diff --git a/ld/ChangeLog b/ld/ChangeLog index 4b42f05..1f80479 100644 --- a/ld/ChangeLog +++ b/ld/ChangeLog @@ -1,3 +1,10 @@ +2020-09-08 Jozef Lawrynowicz + + * testsuite/ld-msp430-elf/msp430-elf.exp: Run new tests. + * testsuite/ld-msp430-elf/uleb128.s: New test. + * testsuite/ld-msp430-elf/uleb128_430.d: New test. + * testsuite/ld-msp430-elf/uleb128_430x.d: New test. + 2020-09-08 Alan Modra * testsuite/ld-elf/pr26580-a.s, -- cgit v1.1