diff options
Diffstat (limited to 'gas')
| -rw-r--r-- | gas/ChangeLog | 20 | ||||
| -rw-r--r-- | gas/config/tc-avr.c | 130 | ||||
| -rw-r--r-- | gas/config/tc-avr.h | 23 | ||||
| -rw-r--r-- | gas/testsuite/ChangeLog | 6 | ||||
| -rw-r--r-- | gas/testsuite/gas/avr/diffreloc_withrelax.d | 16 | ||||
| -rw-r--r-- | gas/testsuite/gas/avr/noreloc_withoutrelax.d | 11 | ||||
| -rw-r--r-- | gas/testsuite/gas/avr/relax.s | 12 |
7 files changed, 215 insertions, 3 deletions
diff --git a/gas/ChangeLog b/gas/ChangeLog index 326b47c..d7e5b4a 100644 --- a/gas/ChangeLog +++ b/gas/ChangeLog @@ -1,3 +1,23 @@ +2014-04-10 Senthil Kumar Selvaraj <senthil_kumar.selvaraj@atmel.com> + + * config/tc-avr.c: Add new flag mlink-relax. + (md_show_usage): Add flag and help text. + (md_parse_option): Record whether link relax is turned on. + (relaxable_section): New. + (avr_validate_fix_sub): New. + (avr_force_relocation): New. + (md_apply_fix): Generate DIFF reloc. + (avr_allow_local_subtract): New. + + * config/tc-avr.h (TC_LINKRELAX_FIXUP): Define to 0. + (TC_FORCE_RELOCATION): Define. + (TC_FORCE_RELOCATION_SUB_SAME): Define. + (TC_VALIDATE_FIX_SUB): Define. + (avr_force_relocation): Declare. + (avr_validate_fix_sub): Declare. + (md_allow_local_subtract): Define. + (avr_allow_local_subtract): Declare. + 2014-04-10 Andrew Bennett <andrew.bennett@imgtec.com> * config/tc-mips.c (mips_cpu_info_table): Add P5600 diff --git a/gas/config/tc-avr.c b/gas/config/tc-avr.c index ce9708e..e4bc59c 100644 --- a/gas/config/tc-avr.c +++ b/gas/config/tc-avr.c @@ -338,9 +338,11 @@ struct avr_opt_s int all_opcodes; /* -mall-opcodes: accept all known AVR opcodes. */ int no_skip_bug; /* -mno-skip-bug: no warnings for skipping 2-word insns. */ int no_wrap; /* -mno-wrap: reject rjmp/rcall with 8K wrap-around. */ + int link_relax; /* -mlink-relax: generate relocations for linker + relaxation. */ }; -static struct avr_opt_s avr_opt = { 0, 0, 0 }; +static struct avr_opt_s avr_opt = { 0, 0, 0, 0 }; const char EXP_CHARS[] = "eE"; const char FLT_CHARS[] = "dD"; @@ -401,7 +403,8 @@ enum options OPTION_ALL_OPCODES = OPTION_MD_BASE + 1, OPTION_NO_SKIP_BUG, OPTION_NO_WRAP, - OPTION_ISA_RMW + OPTION_ISA_RMW, + OPTION_LINK_RELAX }; struct option md_longopts[] = @@ -411,6 +414,7 @@ struct option md_longopts[] = { "mno-skip-bug", no_argument, NULL, OPTION_NO_SKIP_BUG }, { "mno-wrap", no_argument, NULL, OPTION_NO_WRAP }, { "mrmw", no_argument, NULL, OPTION_ISA_RMW }, + { "mlink-relax", no_argument, NULL, OPTION_LINK_RELAX }, { NULL, no_argument, NULL, 0 } }; @@ -517,6 +521,7 @@ md_show_usage (FILE *stream) " -mno-wrap reject rjmp/rcall instructions with 8K wrap-around\n" " (default for avr3, avr5)\n" " -mrmw accept Read-Modify-Write instructions\n" + " -mlink-relax generate relocations for linker relaxation\n" )); show_mcu_list (stream); } @@ -587,6 +592,9 @@ md_parse_option (int c, char *arg) case OPTION_ISA_RMW: specified_mcu.isa |= AVR_ISA_RMW; return 1; + case OPTION_LINK_RELAX: + avr_opt.link_relax = 1; + return 1; } return 0; @@ -637,6 +645,7 @@ md_begin (void) } bfd_set_arch_mach (stdoutput, TARGET_ARCH, avr_mcu->mach); + linkrelax = avr_opt.link_relax; } /* Resolve STR as a constant expression and return the result. @@ -1200,6 +1209,53 @@ md_pcrel_from_section (fixS *fixp, segT sec) return fixp->fx_frag->fr_address + fixp->fx_where; } +static bfd_boolean +relaxable_section (asection *sec) +{ + return (sec->flags & SEC_DEBUGGING) == 0; +} + +/* Does whatever the xtensa port does. */ +int +avr_validate_fix_sub (fixS *fix) +{ + segT add_symbol_segment, sub_symbol_segment; + + /* The difference of two symbols should be resolved by the assembler when + linkrelax is not set. If the linker may relax the section containing + the symbols, then an Xtensa DIFF relocation must be generated so that + the linker knows to adjust the difference value. */ + if (!linkrelax || fix->fx_addsy == NULL) + return 0; + + /* Make sure both symbols are in the same segment, and that segment is + "normal" and relaxable. If the segment is not "normal", then the + fix is not valid. If the segment is not "relaxable", then the fix + should have been handled earlier. */ + add_symbol_segment = S_GET_SEGMENT (fix->fx_addsy); + if (! SEG_NORMAL (add_symbol_segment) || + ! relaxable_section (add_symbol_segment)) + return 0; + + sub_symbol_segment = S_GET_SEGMENT (fix->fx_subsy); + return (sub_symbol_segment == add_symbol_segment); +} + +/* TC_FORCE_RELOCATION hook */ + +/* If linkrelax is turned on, and the symbol to relocate + against is in a relaxable segment, don't compute the value - + generate a relocation instead. */ +int +avr_force_relocation (fixS *fix) +{ + if (linkrelax && fix->fx_addsy + && relaxable_section (S_GET_SEGMENT (fix->fx_addsy))) + return 1; + + return generic_force_reloc (fix); +} + /* GAS will call this for each fixup. It should store the correct value in the object file. */ @@ -1223,11 +1279,47 @@ md_apply_fix (fixS *fixP, valueT * valP, segT seg) fixP->fx_done = 1; } } - + else if (linkrelax && fixP->fx_subsy) + { + /* For a subtraction relocation expression, generate one + of the DIFF relocs, with the value being the difference. + Note that a sym1 - sym2 expression is adjusted into a + section_start_sym + sym4_offset_from_section_start - sym1 + expression. fixP->fx_addsy holds the section start symbol, + fixP->fx_offset holds sym2's offset, and fixP->fx_subsy + holds sym1. Calculate the current difference and write value, + but leave fx_offset as is - during relaxation, + fx_offset - value gives sym1's value */ + + switch (fixP->fx_r_type) + { + case BFD_RELOC_8: + fixP->fx_r_type = BFD_RELOC_AVR_DIFF8; + break; + case BFD_RELOC_16: + fixP->fx_r_type = BFD_RELOC_AVR_DIFF16; + break; + case BFD_RELOC_32: + fixP->fx_r_type = BFD_RELOC_AVR_DIFF32; + break; + default: + as_bad_where (fixP->fx_file, fixP->fx_line, _("expression too complex")); + break; + } + + value = S_GET_VALUE (fixP->fx_addsy) + + fixP->fx_offset - S_GET_VALUE (fixP->fx_subsy); + + fixP->fx_subsy = NULL; + } /* We don't actually support subtracting a symbol. */ if (fixP->fx_subsy != (symbolS *) NULL) as_bad_where (fixP->fx_file, fixP->fx_line, _("expression too complex")); + /* For the DIFF relocs, write the value into the object file while still + keeping fx_done FALSE, as both the difference (recorded in the object file) + and the sym offset (part of fixP) are needed at link relax time */ + where = (unsigned char *) fixP->fx_frag->fr_literal + fixP->fx_where; switch (fixP->fx_r_type) { default: @@ -1237,6 +1329,16 @@ md_apply_fix (fixS *fixP, valueT * valP, segT seg) case BFD_RELOC_AVR_13_PCREL: case BFD_RELOC_32: case BFD_RELOC_16: + break; + case BFD_RELOC_AVR_DIFF8: + *where = value; + break; + case BFD_RELOC_AVR_DIFF16: + bfd_putl16 ((bfd_vma) value, where); + break; + case BFD_RELOC_AVR_DIFF32: + bfd_putl32 ((bfd_vma) value, where); + break; case BFD_RELOC_AVR_CALL: break; } @@ -1654,3 +1756,25 @@ tc_cfi_frame_initial_instructions (void) do not line up the same way as for targers that use pre-decrement. */ cfi_add_CFA_offset (DWARF2_DEFAULT_RETURN_COLUMN, 1-return_size); } + +bfd_boolean +avr_allow_local_subtract (expressionS * left, + expressionS * right, + segT section) +{ + /* If we are not in relaxation mode, subtraction is OK. */ + if (!linkrelax) + return TRUE; + + /* If the symbols are not in a code section then they are OK. */ + if ((section->flags & SEC_CODE) == 0) + return TRUE; + + if (left->X_add_symbol == right->X_add_symbol) + return TRUE; + + /* We have to assume that there may be instructions between the + two symbols and that relaxation may increase the distance between + them. */ + return FALSE; +} diff --git a/gas/config/tc-avr.h b/gas/config/tc-avr.h index df75ac7..fb596ad 100644 --- a/gas/config/tc-avr.h +++ b/gas/config/tc-avr.h @@ -112,6 +112,18 @@ extern void avr_cons_fix_new (fragS *,int, int, expressionS *, visible symbols can be overridden. */ #define EXTERN_FORCE_RELOC 0 +/* If defined, this macro allows control over whether fixups for a + given section will be processed when the linkrelax variable is + set. Define it to zero and handle things in md_apply_fix instead.*/ +#define TC_LINKRELAX_FIXUP(SEG) 0 + +/* If this macro returns non-zero, it guarantees that a relocation will be emitted + even when the value can be resolved locally. Do that if linkrelax is turned on */ +#define TC_FORCE_RELOCATION(fix) avr_force_relocation (fix) +#define TC_FORCE_RELOCATION_SUB_SAME(fix, seg) \ + (! SEG_NORMAL (seg) || avr_force_relocation (fix)) +extern int avr_force_relocation (struct fix *); + /* Values passed to md_apply_fix don't include the symbol value. */ #define MD_APPLY_SYM_VALUE(FIX) 0 @@ -169,6 +181,12 @@ extern long md_pcrel_from_section (struct fix *, segT); goto SKIP; \ } +/* This macro is evaluated for any fixup with a fx_subsy that + fixup_segment cannot reduce to a number. If the macro returns + false an error will be reported. */ +#define TC_VALIDATE_FIX_SUB(fix, seg) avr_validate_fix_sub (fix) +extern int avr_validate_fix_sub (struct fix *); + /* This target is buggy, and sets fix size too large. */ #define TC_FX_SIZE_SLACK(FIX) 2 @@ -190,3 +208,8 @@ extern long md_pcrel_from_section (struct fix *, segT); /* Define a hook to setup initial CFI state. */ extern void tc_cfi_frame_initial_instructions (void); #define tc_cfi_frame_initial_instructions tc_cfi_frame_initial_instructions + +/* The difference between same-section symbols may be affected by linker + relaxation, so do not resolve such expressions in the assembler. */ +#define md_allow_local_subtract(l,r,s) avr_allow_local_subtract (l, r, s) +extern bfd_boolean avr_allow_local_subtract (expressionS *, expressionS *, segT); diff --git a/gas/testsuite/ChangeLog b/gas/testsuite/ChangeLog index 61b42dd..30d957d 100644 --- a/gas/testsuite/ChangeLog +++ b/gas/testsuite/ChangeLog @@ -1,3 +1,9 @@ +2014-04-10 Senthil Kumar Selvaraj <senthil_kumar.selvaraj@atmel.com> + + * gas/avr/diffreloc_withrelax.d: New testcase. + * gas/avr/noreloc_withoutrelax.d: Likewise. + * gas/avr/relax.s: Likewise. + 2014-04-04 Ilya Tocar <ilya.tocar@intel.com> * gas/i386/i386.exp: Run SE1 tests. diff --git a/gas/testsuite/gas/avr/diffreloc_withrelax.d b/gas/testsuite/gas/avr/diffreloc_withrelax.d new file mode 100644 index 0000000..6d5bd2e --- /dev/null +++ b/gas/testsuite/gas/avr/diffreloc_withrelax.d @@ -0,0 +1,16 @@ +#name: AVR DIFF relocs with link relax +#as: -mmcu=avrxmega2 -mlink-relax +#source: relax.s +#objdump: -r +#target: avr-*-* + +.*: file format elf32-avr + +RELOCATION RECORDS FOR \[.text\]: +OFFSET TYPE VALUE +00000000 R_AVR_CALL .text + + +RELOCATION RECORDS FOR \[.data\]: +OFFSET TYPE VALUE +00000000 R_AVR_DIFF16 .text\+0x00000004 diff --git a/gas/testsuite/gas/avr/noreloc_withoutrelax.d b/gas/testsuite/gas/avr/noreloc_withoutrelax.d new file mode 100644 index 0000000..daaaeb2 --- /dev/null +++ b/gas/testsuite/gas/avr/noreloc_withoutrelax.d @@ -0,0 +1,11 @@ +#name: AVR no DIFF relocs without link relax +#as: -mmcu=avrxmega2 +#objdump: -r +#source: relax.s +#target: avr-*-* + +.*: file format elf32-avr + +RELOCATION RECORDS FOR \[.text\]: +OFFSET TYPE VALUE +00000000 R_AVR_CALL .text diff --git a/gas/testsuite/gas/avr/relax.s b/gas/testsuite/gas/avr/relax.s new file mode 100644 index 0000000..dc6b262 --- /dev/null +++ b/gas/testsuite/gas/avr/relax.s @@ -0,0 +1,12 @@ + .file "diffreloc.s" +.section .text,"ax",@progbits +main: +L1: + jmp L1 +L2: +.global x + .section .data + .type x, @object + .size x, 2 +x: + .word L2 - L1 |