diff options
Diffstat (limited to 'backends/platform/ds/arm9')
| -rw-r--r-- | backends/platform/ds/arm9/source/dsloader.cpp | 55 |
1 files changed, 52 insertions, 3 deletions
diff --git a/backends/platform/ds/arm9/source/dsloader.cpp b/backends/platform/ds/arm9/source/dsloader.cpp index 2f953cc33b..c0e8b63dbc 100644 --- a/backends/platform/ds/arm9/source/dsloader.cpp +++ b/backends/platform/ds/arm9/source/dsloader.cpp @@ -97,16 +97,18 @@ bool DLObject::relocate(Common::SeekableReadStream* DLFile, unsigned long offset int a = 0; unsigned int relocation = 0; + // Loop over relocation entries for (int i = 0; i < cnt; i++) { + // Get the symbol this relocation entry is referring to Elf32_Sym *sym = (Elf32_Sym *)(_symtab) + (REL_INDEX(rel[i].r_info)); + // Get the target instruction in the code unsigned int *target = (unsigned int *)((char *)relSegment + rel[i].r_offset); unsigned int origTarget = *target; // Save for debugging - //DBG("%d, ", REL_TYPE(rel[i].r_info)); - + // Act differently based on the type of relocation switch (REL_TYPE(rel[i].r_info)) { case R_ARM_ABS32: @@ -151,6 +153,48 @@ bool DLObject::relocate(Common::SeekableReadStream* DLFile, unsigned long offset } break; + case R_ARM_CALL: + if (sym->st_shndx < SHN_LOPROC) { // Only shift for plugin section. + a = *target & 0x00ffffff; + a = (a << 8) >> 6; // Calculate addend by sign-extending (insn[23:0] << 2) + relocation = a + (Elf32_Addr)_segment; // Shift by main offset + + /*TODO: + * if (SYM_TYPE(sym->st_info) == STT_FUNC && symbol addresses a thumb instruction) { + * relocation |= 1; + * } + */ + + relocation = relocation - rel[i].r_offset; + relocation = relocation >> 2; + *target &= 0xff000000; // Clean lower 26 target bits + *target |= (relocation & 0x00ffffff); + + DBG("R_ARM_CALL: i=%d, a=%x, origTarget=%x, target=%x\n", i, a, origTarget, *target); + } + break; + + case R_ARM_JUMP24: + if (sym->st_shndx < SHN_LOPROC) { // Only shift for plugin section. + a = *target & 0x00ffffff; + a = (a << 8) >> 6; // Calculate addend by sign-extending (insn[23:0] << 2) + relocation = a + (Elf32_Addr)_segment; // Shift by main offset + + /*TODO: + * if (SYM_TYPE(sym->st_info) == STT_FUNC && symbol addresses a thumb instruction) { + * relocation |= 1; + * } + */ + + relocation = relocation - rel[i].r_offset; + relocation = relocation >> 2; + *target &= 0xff000000; // Clean lower 26 target bits + *target |= (relocation & 0x00ffffff); + + DBG("R_ARM_CALL: i=%d, a=%x, origTarget=%x, target=%x\n", i, a, origTarget, *target); + } + break; + case R_ARM_V4BX: DBG("R_ARM_V4BX: No relocation calculation necessary\n"); break; @@ -365,12 +409,17 @@ bool DLObject::relocateRels(Common::SeekableReadStream* DLFile, Elf32_Ehdr *ehdr Elf32_Shdr *curShdr = &(shdr[i]); //Elf32_Shdr *linkShdr = &(shdr[curShdr->sh_info]); - if (curShdr->sh_type == SHT_REL && // Check for a relocation section + if ((curShdr->sh_type == SHT_REL || curShdr->sh_type == SHT_RELA) && // Check for a relocation section curShdr->sh_entsize == sizeof(Elf32_Rel) && // Check for proper relocation size (int)curShdr->sh_link == _symtab_sect && // Check that the sh_link connects to our symbol table curShdr->sh_info < ehdr->e_shnum && // Check that the relocated section exists (shdr[curShdr->sh_info].sh_flags & SHF_ALLOC)) { // Check if relocated section resides in memory + if (curShdr->sh_type == SHT_RELA) { + seterror("RELA entries not supported for ARM yet!\n"); + return false; + } + if (!relocate(DLFile, curShdr->sh_offset, curShdr->sh_size, _segment)) { return false; } |