/* True for mips16 instructions that jump to an absolute address. */
unsigned int mips16_absolute_jump_p : 1;
+
+ /* True if this instruction is complete. */
+ unsigned int complete_p : 1;
};
/* The ABI to use. */
insn->fixed_p = (mips_opts.noreorder > 0);
insn->noreorder_p = (mips_opts.noreorder > 0);
insn->mips16_absolute_jump_p = 0;
+ insn->complete_p = 0;
}
/* Record the current MIPS16 mode in now_seg. */
return 0;
}
+#define BASE_REG_EQ(INSN1, INSN2) \
+ ((((INSN1) >> OP_SH_RS) & OP_MASK_RS) \
+ == (((INSN2) >> OP_SH_RS) & OP_MASK_RS))
+
+/* Return the minimum alignment for this store instruction. */
+
+static int
+fix_24k_align_to (const struct mips_opcode *mo)
+{
+ if (strcmp (mo->name, "sh") == 0)
+ return 2;
+
+ if (strcmp (mo->name, "swc1") == 0
+ || strcmp (mo->name, "swc2") == 0
+ || strcmp (mo->name, "sw") == 0
+ || strcmp (mo->name, "sc") == 0
+ || strcmp (mo->name, "s.s") == 0)
+ return 4;
+
+ if (strcmp (mo->name, "sdc1") == 0
+ || strcmp (mo->name, "sdc2") == 0
+ || strcmp (mo->name, "s.d") == 0)
+ return 8;
+
+ /* sb, swl, swr */
+ return 1;
+}
+
+struct fix_24k_store_info
+ {
+ /* Immediate offset, if any, for this store instruction. */
+ short off;
+ /* Alignment required by this store instruction. */
+ int align_to;
+ /* True for register offsets. */
+ int register_offset;
+ };
+
+/* Comparison function used by qsort. */
+
+static int
+fix_24k_sort (const void *a, const void *b)
+{
+ const struct fix_24k_store_info *pos1 = a;
+ const struct fix_24k_store_info *pos2 = b;
+
+ return (pos1->off - pos2->off);
+}
+
+/* INSN is a store instruction. Try to record the store information
+ in STINFO. Return false if the information isn't known. */
+
+static bfd_boolean
+fix_24k_record_store_info (struct fix_24k_store_info *stinfo,
+ const struct mips_cl_insn *insn)
+{
+ /* The instruction must have a known offset. */
+ if (!insn->complete_p || !strstr (insn->insn_mo->args, "o("))
+ return FALSE;
+
+ stinfo->off = (insn->insn_opcode >> OP_SH_IMMEDIATE) & OP_MASK_IMMEDIATE;
+ stinfo->align_to = fix_24k_align_to (insn->insn_mo);
+ return TRUE;
+}
+
+/* 24K Errata: Lost Data on Stores During Refill.
+
+ Problem: The FSB (fetch store buffer) acts as an intermediate buffer
+ for the data cache refills and store data. The following describes
+ the scenario where the store data could be lost.
+
+ * A data cache miss, due to either a load or a store, causing fill
+ data to be supplied by the memory subsystem
+ * The first three doublewords of fill data are returned and written
+ into the cache
+ * A sequence of four stores occurs in consecutive cycles around the
+ final doubleword of the fill:
+ * Store A
+ * Store B
+ * Store C
+ * Zero, One or more instructions
+ * Store D
+
+ The four stores A-D must be to different doublewords of the line that
+ is being filled. The fourth instruction in the sequence above permits
+ the fill of the final doubleword to be transferred from the FSB into
+ the cache. In the sequence above, the stores may be either integer
+ (sb, sh, sw, swr, swl, sc) or coprocessor (swc1/swc2, sdc1/sdc2,
+ swxc1, sdxc1, suxc1) stores, as long as the four stores are to
+ different doublewords on the line. If the floating point unit is
+ running in 1:2 mode, it is not possible to create the sequence above
+ using only floating point store instructions.
+
+ In this case, the cache line being filled is incorrectly marked
+ invalid, thereby losing the data from any store to the line that
+ occurs between the original miss and the completion of the five
+ cycle sequence shown above.
+
+ The workarounds are:
+
+ * Run the data cache in write-through mode.
+ * Insert a non-store instruction between
+ Store A and Store B or Store B and Store C. */
+
+static int
+nops_for_24k (const struct mips_cl_insn *hist,
+ const struct mips_cl_insn *insn)
+{
+ struct fix_24k_store_info pos[3];
+ int align, i, base_offset;
+
+ /* If INSN is definitely not a store, there's nothing to worry about. */
+ if (insn && (insn->insn_mo->pinfo & INSN_STORE_MEMORY) == 0)
+ return 0;
+
+ /* Likewise, the previous instruction wasn't a store. */
+ if ((hist[0].insn_mo->pinfo & INSN_STORE_MEMORY) == 0)
+ return 0;
+
+ /* If we don't know what came before, assume the worst. */
+ if (hist[1].frag == NULL)
+ return 1;
+
+ /* If the instruction was not a store, there's nothing to worry about. */
+ if ((hist[1].insn_mo->pinfo & INSN_STORE_MEMORY) == 0)
+ return 0;
+
+ /* If we don't know the relationship between the store addresses,
+ assume the worst. */
+ if (insn == NULL
+ || !BASE_REG_EQ (insn->insn_opcode, hist[0].insn_opcode)
+ || !BASE_REG_EQ (insn->insn_opcode, hist[1].insn_opcode))
+ return 1;
+
+ if (!fix_24k_record_store_info (&pos[0], insn)
+ || !fix_24k_record_store_info (&pos[1], &hist[0])
+ || !fix_24k_record_store_info (&pos[2], &hist[1]))
+ return 1;
+
+ qsort (&pos, 3, sizeof (struct fix_24k_store_info), fix_24k_sort);
+
+ /* Pick a value of ALIGN and X such that all offsets are adjusted by
+ X bytes and such that the base register + X is known to be aligned
+ to align bytes. */
+
+ if (((insn->insn_opcode >> OP_SH_RS) & OP_MASK_RS) == SP)
+ align = 8;
+ else
+ {
+ align = pos[0].align_to;
+ base_offset = pos[0].off;
+ for (i = 1; i < 3; i++)
+ if (align < pos[i].align_to)
+ {
+ align = pos[i].align_to;
+ base_offset = pos[i].off;
+ }
+ for (i = 0; i < 3; i++)
+ pos[i].off -= base_offset;
+ }
+
+ pos[0].off &= ~align + 1;
+ pos[1].off &= ~align + 1;
+ pos[2].off &= ~align + 1;
+
+ /* If any two stores write to the same chunk, they also write to the
+ same doubleword. The offsets are still sorted at this point. */
+ if (pos[0].off == pos[1].off || pos[1].off == pos[2].off)
+ return 0;
+
+ /* A range of at least 9 bytes is needed for the stores to be in
+ non-overlapping doublewords. */
+ if (pos[2].off - pos[0].off <= 8)
+ return 0;
+
+ if (pos[2].off - pos[1].off >= 24
+ || pos[1].off - pos[0].off >= 24
+ || pos[2].off - pos[0].off >= 32)
+ return 0;
+
+ return 1;
+}
+
/* Return the number of nops that would be needed if instruction INSN
immediately followed the MAX_NOPS instructions given by HIST,
where HIST[0] is the most recent instruction. If INSN is null,
nops = tmp_nops;
}
+ if (mips_fix_24k)
+ {
+ tmp_nops = nops_for_24k (hist, insn);
+ if (tmp_nops > nops)
+ nops = tmp_nops;
+ }
+
return nops;
}
pinfo = ip->insn_mo->pinfo;
pinfo2 = ip->insn_mo->pinfo2;
+ if (address_expr == NULL)
+ ip->complete_p = 1;
+ else if (*reloc_type <= BFD_RELOC_UNUSED
+ && address_expr->X_op == O_constant)
+ {
+ unsigned int tmp;
+
+ ip->complete_p = 1;
+ switch (*reloc_type)
+ {
+ case BFD_RELOC_32:
+ ip->insn_opcode |= address_expr->X_add_number;
+ break;
+
+ case BFD_RELOC_MIPS_HIGHEST:
+ tmp = (address_expr->X_add_number + 0x800080008000ull) >> 48;
+ ip->insn_opcode |= tmp & 0xffff;
+ break;
+
+ case BFD_RELOC_MIPS_HIGHER:
+ tmp = (address_expr->X_add_number + 0x80008000ull) >> 32;
+ ip->insn_opcode |= tmp & 0xffff;
+ break;
+
+ case BFD_RELOC_HI16_S:
+ tmp = (address_expr->X_add_number + 0x8000) >> 16;
+ ip->insn_opcode |= tmp & 0xffff;
+ break;
+
+ case BFD_RELOC_HI16:
+ ip->insn_opcode |= (address_expr->X_add_number >> 16) & 0xffff;
+ break;
+
+ case BFD_RELOC_UNUSED:
+ case BFD_RELOC_LO16:
+ case BFD_RELOC_MIPS_GOT_DISP:
+ ip->insn_opcode |= address_expr->X_add_number & 0xffff;
+ break;
+
+ case BFD_RELOC_MIPS_JMP:
+ if ((address_expr->X_add_number & 3) != 0)
+ as_bad (_("jump to misaligned address (0x%lx)"),
+ (unsigned long) address_expr->X_add_number);
+ ip->insn_opcode |= (address_expr->X_add_number >> 2) & 0x3ffffff;
+ ip->complete_p = 0;
+ break;
+
+ case BFD_RELOC_MIPS16_JMP:
+ if ((address_expr->X_add_number & 3) != 0)
+ as_bad (_("jump to misaligned address (0x%lx)"),
+ (unsigned long) address_expr->X_add_number);
+ ip->insn_opcode |=
+ (((address_expr->X_add_number & 0x7c0000) << 3)
+ | ((address_expr->X_add_number & 0xf800000) >> 7)
+ | ((address_expr->X_add_number & 0x3fffc) >> 2));
+ ip->complete_p = 0;
+ break;
+
+ case BFD_RELOC_16_PCREL_S2:
+ if ((address_expr->X_add_number & 3) != 0)
+ as_bad (_("branch to misaligned address (0x%lx)"),
+ (unsigned long) address_expr->X_add_number);
+ if (mips_relax_branch)
+ goto need_reloc;
+ if ((address_expr->X_add_number + 0x20000) & ~0x3ffff)
+ as_bad (_("branch address range overflow (0x%lx)"),
+ (unsigned long) address_expr->X_add_number);
+ ip->insn_opcode |= (address_expr->X_add_number >> 2) & 0xffff;
+ ip->complete_p = 0;
+ break;
+
+ default:
+ internalError ();
+ }
+ }
+
if (mips_relax.sequence != 2 && !mips_opts.noreorder)
{
/* There are a lot of optimizations we could do that we don't.
if (address_expr != NULL && *reloc_type <= BFD_RELOC_UNUSED)
{
- if (address_expr->X_op == O_constant)
- {
- unsigned int tmp;
-
- switch (*reloc_type)
- {
- case BFD_RELOC_32:
- ip->insn_opcode |= address_expr->X_add_number;
- break;
-
- case BFD_RELOC_MIPS_HIGHEST:
- tmp = (address_expr->X_add_number + 0x800080008000ull) >> 48;
- ip->insn_opcode |= tmp & 0xffff;
- break;
-
- case BFD_RELOC_MIPS_HIGHER:
- tmp = (address_expr->X_add_number + 0x80008000ull) >> 32;
- ip->insn_opcode |= tmp & 0xffff;
- break;
-
- case BFD_RELOC_HI16_S:
- tmp = (address_expr->X_add_number + 0x8000) >> 16;
- ip->insn_opcode |= tmp & 0xffff;
- break;
-
- case BFD_RELOC_HI16:
- ip->insn_opcode |= (address_expr->X_add_number >> 16) & 0xffff;
- break;
-
- case BFD_RELOC_UNUSED:
- case BFD_RELOC_LO16:
- case BFD_RELOC_MIPS_GOT_DISP:
- ip->insn_opcode |= address_expr->X_add_number & 0xffff;
- break;
-
- case BFD_RELOC_MIPS_JMP:
- if ((address_expr->X_add_number & 3) != 0)
- as_bad (_("jump to misaligned address (0x%lx)"),
- (unsigned long) address_expr->X_add_number);
- ip->insn_opcode |= (address_expr->X_add_number >> 2) & 0x3ffffff;
- break;
-
- case BFD_RELOC_MIPS16_JMP:
- if ((address_expr->X_add_number & 3) != 0)
- as_bad (_("jump to misaligned address (0x%lx)"),
- (unsigned long) address_expr->X_add_number);
- ip->insn_opcode |=
- (((address_expr->X_add_number & 0x7c0000) << 3)
- | ((address_expr->X_add_number & 0xf800000) >> 7)
- | ((address_expr->X_add_number & 0x3fffc) >> 2));
- break;
-
- case BFD_RELOC_16_PCREL_S2:
- if ((address_expr->X_add_number & 3) != 0)
- as_bad (_("branch to misaligned address (0x%lx)"),
- (unsigned long) address_expr->X_add_number);
- if (mips_relax_branch)
- goto need_reloc;
- if ((address_expr->X_add_number + 0x20000) & ~0x3ffff)
- as_bad (_("branch address range overflow (0x%lx)"),
- (unsigned long) address_expr->X_add_number);
- ip->insn_opcode |= (address_expr->X_add_number >> 2) & 0xffff;
- break;
-
- default:
- internalError ();
- }
- }
- else if (*reloc_type < BFD_RELOC_UNUSED)
+ if (!ip->complete_p
+ && *reloc_type < BFD_RELOC_UNUSED)
need_reloc:
{
reloc_howto_type *howto;