diff options
Diffstat (limited to 'gas/config/tc-sparc.c')
| -rw-r--r-- | gas/config/tc-sparc.c | 103 |
1 files changed, 102 insertions, 1 deletions
diff --git a/gas/config/tc-sparc.c b/gas/config/tc-sparc.c index 149610e..bd086d2 100644 --- a/gas/config/tc-sparc.c +++ b/gas/config/tc-sparc.c @@ -91,6 +91,9 @@ static enum sparc_opcode_arch_val warn_after_architecture; has been used in -64. */ static int no_undeclared_regs; +/* Non-zero if we should try to relax jumps and calls. */ +static int sparc_relax; + /* Non-zero if we are generating PIC code. */ int sparc_pic_code; @@ -415,6 +418,10 @@ struct option md_longopts[] = { #define OPTION_UNDECLARED_REGS (OPTION_MD_BASE + 13) {"undeclared-regs", no_argument, NULL, OPTION_UNDECLARED_REGS}, #endif +#define OPTION_RELAX (OPTION_MD_BASE + 14) + {"relax", no_argument, NULL, OPTION_RELAX}, +#define OPTION_NO_RELAX (OPTION_MD_BASE + 15) + {"no-relax", no_argument, NULL, OPTION_NO_RELAX}, {NULL, no_argument, NULL, 0} }; size_t md_longopts_size = sizeof(md_longopts); @@ -574,6 +581,14 @@ md_parse_option (c, arg) break; #endif + case OPTION_RELAX: + sparc_relax = 1; + break; + + case OPTION_NO_RELAX: + sparc_relax = 0; + break; + default: return 0; } @@ -605,7 +620,9 @@ md_show_usage (stream) specify variant of SPARC architecture\n\ -bump warn when assembler switches architectures\n\ -sparc ignored\n\ ---enforce-aligned-data force .long, etc., to be aligned correctly\n")); +--enforce-aligned-data force .long, etc., to be aligned correctly\n\ +-relax relax jumps and branches (default)\n\ +-no-relax avoid changing any jumps and branches\n")); #ifdef OBJ_AOUT fprintf (stream, _("\ -k generate PIC\n")); @@ -2915,7 +2932,91 @@ md_apply_fix3 (fixP, value, segment) || fixP->fx_addsy == NULL || symbol_section_p (fixP->fx_addsy)) ++val; + insn |= val & 0x3fffffff; + + /* See if we have a delay slot */ + if (sparc_relax && fixP->fx_where + 8 <= fixP->fx_frag->fr_fix) + { +#define G0 0 +#define O7 15 +#define XCC (2 << 20) +#define COND(x) (((x)&0xf)<<25) +#define CONDA COND(0x8) +#define INSN_BPA (F2(0,1) | CONDA | BPRED | XCC) +#define INSN_BA (F2(0,2) | CONDA) +#define INSN_OR F3(2, 0x2, 0) +#define INSN_NOP F2(0,4) + + long delay; + + /* If the instruction is a call with either: + restore + arithmetic instruction with rd == %o7 + where rs1 != %o7 and rs2 if it is register != %o7 + then we can optimize if the call destination is near + by changing the call into a branch always. */ + if (INSN_BIG_ENDIAN) + delay = bfd_getb32 ((unsigned char *) buf + 4); + else + delay = bfd_getl32 ((unsigned char *) buf + 4); + if ((insn & OP(~0)) != OP(1) || (delay & OP(~0)) != OP(2)) + break; + if ((delay & OP3(~0)) != OP3(0x3d) /* restore */ + && ((delay & OP3(0x28)) != 0 /* arithmetic */ + || ((delay & RD(~0)) != RD(O7)))) + break; + if ((delay & RS1(~0)) == RS1(O7) + || ((delay & F3I(~0)) == 0 + && (delay & RS2(~0)) == RS2(O7))) + break; + /* Ensure the branch will fit into simm22. */ + if ((val & 0x3fe00000) + && (val & 0x3fe00000) != 0x3fe00000) + break; + /* Check if the arch is v9 and branch will fit + into simm19. */ + if (((val & 0x3c0000) == 0 + || (val & 0x3c0000) == 0x3c0000) + && (sparc_arch_size == 64 + || current_architecture >= SPARC_OPCODE_ARCH_V9)) + /* ba,pt %xcc */ + insn = INSN_BPA | (val & 0x7ffff); + else + /* ba */ + insn = INSN_BA | (val & 0x3fffff); + if (fixP->fx_where >= 4 + && ((delay & (0xffffffff ^ RS1(~0))) + == (INSN_OR | RD(O7) | RS2(G0)))) + { + long setter; + int reg; + + if (INSN_BIG_ENDIAN) + setter = bfd_getb32 ((unsigned char *) buf - 4); + else + setter = bfd_getl32 ((unsigned char *) buf - 4); + if ((setter & (0xffffffff ^ RD(~0))) + != (INSN_OR | RS1(O7) | RS2(G0))) + break; + /* The sequence was + or %o7, %g0, %rN + call foo + or %rN, %g0, %o7 + + If call foo was replaced with ba, replace + or %rN, %g0, %o7 with nop. */ + reg = (delay & RS1(~0)) >> 14; + if (reg != ((setter & RD(~0)) >> 25) + || reg == G0 || reg == O7) + break; + + if (INSN_BIG_ENDIAN) + bfd_putb32 (INSN_NOP, (unsigned char *) buf + 4); + else + bfd_putl32 (INSN_NOP, (unsigned char *) buf + 4); + } + } break; case BFD_RELOC_SPARC_11: |