From 5bf68bc39976903929f730b6eed18686c3563c05 Mon Sep 17 00:00:00 2001 From: Nagaraju Mekala Date: Mon, 28 Aug 2017 19:53:56 -0700 Subject: [PATCH] Fixup MicroBlaze debug_loc sections after linker relaxation Fixup debug_loc sections after linker relaxation Adds a new reloctype R_MICROBLAZE_32_NONE, used for passing reloc info from the assembler to the linker when the linker manages to fully resolve a local symbol reference. This is a workaround for design flaws in the assembler to linker interface with regards to linker relaxation. 08/2018 Rebased for binutils 2.31 - Some RELOC_NUMBERs were added upstream, rebased to use 33 instead of 30 Signed-off-by: Edgar E. Iglesias Signed-off-by: Nagaraju Mekala Signed-off-by: Manjukumar Matha Signed-off-by: Alejandro Enedino Hernandez Samaniego Upstream-Status: Pending --- bfd/bfd-in2.h | 9 +++++++-- bfd/elf32-microblaze.c | 45 ++++++++++++++++++++++++++++++++++++++------- bfd/libbfd.h | 1 + bfd/reloc.c | 6 ++++++ binutils/readelf.c | 4 ++++ gas/config/tc-microblaze.c | 5 ++++- include/elf/microblaze.h | 1 + 7 files changed, 61 insertions(+), 10 deletions(-) Index: git/bfd/bfd-in2.h =================================================================== --- git.orig/bfd/bfd-in2.h +++ git/bfd/bfd-in2.h @@ -5791,10 +5791,15 @@ value relative to the read-write small d expressions of the form "Symbol Op Symbol" */ BFD_RELOC_MICROBLAZE_32_SYM_OP_SYM, -/* This is a 64 bit reloc that stores the 32 bit pc relative +/* This is a 32 bit reloc that stores the 32 bit pc relative value in two words (with an imm instruction). No relocation is done here - only used for relaxing */ - BFD_RELOC_MICROBLAZE_64_NONE, + BFD_RELOC_MICROBLAZE_32_NONE, + +/* This is a 64 bit reloc that stores the 32 bit pc relative + * +value in two words (with an imm instruction). No relocation is + * +done here - only used for relaxing */ + BFD_RELOC_MICROBLAZE_64_NONE, /* This is a 64 bit reloc that stores the 32 bit pc relative value in two words (with an imm instruction). The relocation is Index: git/bfd/elf32-microblaze.c =================================================================== --- git.orig/bfd/elf32-microblaze.c +++ git/bfd/elf32-microblaze.c @@ -176,6 +176,20 @@ static reloc_howto_type microblaze_elf_h 0x0000ffff, /* Dest Mask. */ FALSE), /* PC relative offset? */ + HOWTO (R_MICROBLAZE_32_NONE, /* Type. */ + 0, /* Rightshift. */ + 2, /* Size (0 = byte, 1 = short, 2 = long). */ + 32, /* Bitsize. */ + TRUE, /* PC_relative. */ + 0, /* Bitpos. */ + complain_overflow_bitfield, /* Complain on overflow. */ + NULL, /* Special Function. */ + "R_MICROBLAZE_32_NONE",/* Name. */ + FALSE, /* Partial Inplace. */ + 0, /* Source Mask. */ + 0, /* Dest Mask. */ + FALSE), /* PC relative offset? */ + /* This reloc does nothing. Used for relaxation. */ HOWTO (R_MICROBLAZE_64_NONE, /* Type. */ 0, /* Rightshift. */ @@ -562,6 +576,9 @@ microblaze_elf_reloc_type_lookup (bfd * case BFD_RELOC_NONE: microblaze_reloc = R_MICROBLAZE_NONE; break; + case BFD_RELOC_MICROBLAZE_32_NONE: + microblaze_reloc = R_MICROBLAZE_32_NONE; + break; case BFD_RELOC_MICROBLAZE_64_NONE: microblaze_reloc = R_MICROBLAZE_64_NONE; break; @@ -1918,14 +1935,23 @@ microblaze_elf_relax_section (bfd *abfd, } break; case R_MICROBLAZE_NONE: + case R_MICROBLAZE_32_NONE: { /* This was a PC-relative instruction that was completely resolved. */ int sfix, efix; + unsigned int val; bfd_vma target_address; target_address = irel->r_addend + irel->r_offset; sfix = calc_fixup (irel->r_offset, 0, sec); efix = calc_fixup (target_address, 0, sec); + + /* Validate the in-band val. */ + val = bfd_get_32 (abfd, contents + irel->r_offset); + if (val != irel->r_addend && ELF32_R_TYPE (irel->r_info) == R_MICROBLAZE_32_NONE) { + fprintf(stderr, "%d: CORRUPT relax reloc %x %lx\n", __LINE__, val, irel->r_addend); + } + irel->r_addend -= (efix - sfix); /* Should use HOWTO. */ microblaze_bfd_write_imm_value_32 (abfd, contents + irel->r_offset, @@ -1973,12 +1999,16 @@ microblaze_elf_relax_section (bfd *abfd, irelscanend = irelocs + o->reloc_count; for (irelscan = irelocs; irelscan < irelscanend; irelscan++) { - if (ELF32_R_TYPE (irelscan->r_info) == (int) R_MICROBLAZE_NONE) + if (1 && ELF32_R_TYPE (irelscan->r_info) == (int) R_MICROBLAZE_32_NONE) { unsigned int val; isym = isymbuf + ELF32_R_SYM (irelscan->r_info); + /* hax: We only do the following fixup for debug location lists. */ + if (strcmp(".debug_loc", o->name)) + continue; + /* This was a PC-relative instruction that was completely resolved. */ if (ocontents == NULL) { @@ -2003,15 +2033,16 @@ microblaze_elf_relax_section (bfd *abfd, } } - irelscan->r_addend -= calc_fixup (irelscan->r_addend - + isym->st_value, sec); val = bfd_get_32 (abfd, ocontents + irelscan->r_offset); + + if (val != irelscan->r_addend) { + fprintf(stderr, "%d: CORRUPT relax reloc! %x %lx\n", __LINE__, val, irelscan->r_addend); + } + irelscan->r_addend -= calc_fixup (irelscan->r_addend, 0, sec); + microblaze_bfd_write_imm_value_32 (abfd, ocontents + irelscan->r_offset, irelscan->r_addend); } - if (ELF32_R_TYPE (irelscan->r_info) == (int) R_MICROBLAZE_64_NONE) { - fprintf(stderr, "Unhandled NONE 64\n"); - } if (ELF32_R_TYPE (irelscan->r_info) == (int) R_MICROBLAZE_32) { isym = isymbuf + ELF32_R_SYM (irelscan->r_info); @@ -2071,7 +2102,7 @@ microblaze_elf_relax_section (bfd *abfd, elf_section_data (o)->this_hdr.contents = ocontents; } } - irelscan->r_addend -= calc_fixup (irel->r_addend + irelscan->r_addend -= calc_fixup (irelscan->r_addend + isym->st_value, 0, sec); Index: git/bfd/libbfd.h =================================================================== --- git.orig/bfd/libbfd.h +++ git/bfd/libbfd.h @@ -2862,6 +2862,7 @@ static const char *const bfd_reloc_code_ "BFD_RELOC_MICROBLAZE_32_ROSDA", "BFD_RELOC_MICROBLAZE_32_RWSDA", "BFD_RELOC_MICROBLAZE_32_SYM_OP_SYM", + "BFD_RELOC_MICROBLAZE_32_NONE", "BFD_RELOC_MICROBLAZE_64_NONE", "BFD_RELOC_MICROBLAZE_64_GOTPC", "BFD_RELOC_MICROBLAZE_64_GOT", Index: git/bfd/reloc.c =================================================================== --- git.orig/bfd/reloc.c +++ git/bfd/reloc.c @@ -6865,6 +6865,12 @@ ENUMDOC This is a 32 bit reloc for the microblaze to handle expressions of the form "Symbol Op Symbol" ENUM + BFD_RELOC_MICROBLAZE_32_NONE +ENUMDOC + This is a 32 bit reloc that stores the 32 bit pc relative + value in two words (with an imm instruction). No relocation is + done here - only used for relaxing +ENUM BFD_RELOC_MICROBLAZE_64_NONE ENUMDOC This is a 64 bit reloc that stores the 32 bit pc relative Index: git/binutils/readelf.c =================================================================== --- git.orig/binutils/readelf.c +++ git/binutils/readelf.c @@ -12908,6 +12908,10 @@ is_none_reloc (Filedata * filedata, unsi || reloc_type == 32 /* R_AVR_DIFF32. */); case EM_METAG: return reloc_type == 3; /* R_METAG_NONE. */ + case EM_MICROBLAZE: + return reloc_type == 33 /* R_MICROBLAZE_32_NONE. */ + || reloc_type == 0 /* R_MICROBLAZE_NONE. */ + || reloc_type == 9; /* R_MICROBLAZE_64_NONE. */ case EM_NDS32: return (reloc_type == 0 /* R_XTENSA_NONE. */ || reloc_type == 204 /* R_NDS32_DIFF8. */ Index: git/gas/config/tc-microblaze.c =================================================================== --- git.orig/gas/config/tc-microblaze.c +++ git/gas/config/tc-microblaze.c @@ -2201,7 +2201,9 @@ md_apply_fix (fixS * fixP, /* This fixup has been resolved. Create a reloc in case the linker moves code around due to relaxing. */ if (fixP->fx_r_type == BFD_RELOC_64_PCREL) - fixP->fx_r_type = BFD_RELOC_MICROBLAZE_64_NONE; + fixP->fx_r_type = BFD_RELOC_MICROBLAZE_64_NONE; + else if (fixP->fx_r_type == BFD_RELOC_32) + fixP->fx_r_type = BFD_RELOC_MICROBLAZE_32_NONE; else fixP->fx_r_type = BFD_RELOC_NONE; fixP->fx_addsy = section_symbol (absolute_section); @@ -2426,6 +2428,7 @@ tc_gen_reloc (asection * section ATTRIBU switch (fixp->fx_r_type) { case BFD_RELOC_NONE: + case BFD_RELOC_MICROBLAZE_32_NONE: case BFD_RELOC_MICROBLAZE_64_NONE: case BFD_RELOC_32: case BFD_RELOC_MICROBLAZE_32_LO: Index: git/include/elf/microblaze.h =================================================================== --- git.orig/include/elf/microblaze.h +++ git/include/elf/microblaze.h @@ -61,6 +61,7 @@ START_RELOC_NUMBERS (elf_microblaze_relo RELOC_NUMBER (R_MICROBLAZE_TEXTPCREL_64, 30) /* PC-relative TEXT offset. */ RELOC_NUMBER (R_MICROBLAZE_TEXTREL_64, 31) /* TEXT Entry offset 64-bit. */ RELOC_NUMBER (R_MICROBLAZE_TEXTREL_32_LO, 32) /* TEXT Entry offset 32-bit. */ + RELOC_NUMBER (R_MICROBLAZE_32_NONE, 33) END_RELOC_NUMBERS (R_MICROBLAZE_max) /* Global base address names. */