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Diffstat (limited to 'bfd/elf32-v850.c')
-rw-r--r--bfd/elf32-v850.c392
1 files changed, 215 insertions, 177 deletions
diff --git a/bfd/elf32-v850.c b/bfd/elf32-v850.c
index 09eb1ab..d960235 100644
--- a/bfd/elf32-v850.c
+++ b/bfd/elf32-v850.c
@@ -533,6 +533,21 @@ static reloc_howto_type v850_elf_howto_table[] =
0xffffffff, /* src_mask */
0xffffffff, /* dst_mask */
FALSE), /* pcrel_offset */
+
+ /* An ld.bu version of R_V850_LO16. */
+ HOWTO (R_V850_LO16_SPLIT_OFFSET, /* type */
+ 0, /* rightshift */
+ 2, /* size (0 = byte, 1 = short, 2 = long) */
+ 16, /* bitsize */
+ FALSE, /* pc_relative */
+ 0, /* bitpos */
+ complain_overflow_dont, /* complain_on_overflow */
+ v850_elf_reloc, /* special_function */
+ "R_V850_LO16_SPLIT_OFFSET", /* name */
+ FALSE, /* partial_inplace */
+ 0xfffe0020, /* src_mask */
+ 0xfffe0020, /* dst_mask */
+ FALSE), /* pcrel_offset */
};
/* Map BFD reloc types to V850 ELF reloc types. */
@@ -567,6 +582,7 @@ static const struct v850_elf_reloc_map v850_elf_reloc_map[] =
{ BFD_RELOC_V850_TDA_16_16_OFFSET, R_V850_TDA_16_16_OFFSET },
{ BFD_RELOC_V850_TDA_4_5_OFFSET, R_V850_TDA_4_5_OFFSET },
{ BFD_RELOC_V850_TDA_4_4_OFFSET, R_V850_TDA_4_4_OFFSET },
+ { BFD_RELOC_V850_LO16_SPLIT_OFFSET, R_V850_LO16_SPLIT_OFFSET },
{ BFD_RELOC_V850_SDA_16_16_SPLIT_OFFSET, R_V850_SDA_16_16_SPLIT_OFFSET },
{ BFD_RELOC_V850_ZDA_16_16_SPLIT_OFFSET, R_V850_ZDA_16_16_SPLIT_OFFSET },
{ BFD_RELOC_V850_CALLT_6_7_OFFSET, R_V850_CALLT_6_7_OFFSET },
@@ -687,6 +703,7 @@ v850_elf_check_relocs (abfd, info, sec, relocs)
case R_V850_HI16_S:
case R_V850_HI16:
case R_V850_LO16:
+ case R_V850_LO16_SPLIT_OFFSET:
case R_V850_ABS32:
case R_V850_REL32:
case R_V850_16:
@@ -902,6 +919,187 @@ find_remembered_hi16s_reloc (addend, already_found)
return addr;
}
+/* Calculate the final operand value for a R_V850_LO16 or
+ R_V850_LO16_SPLIT_OFFSET. *INSN is the current operand value and
+ ADDEND is the sum of the relocation symbol and offset. Store the
+ operand value in *INSN and return true on success.
+
+ The assembler has already done some of this: If the value stored in
+ the instruction has its 15th bit set, (counting from zero) then the
+ assembler will have added 1 to the value stored in the associated
+ HI16S reloc. So for example, these relocations:
+
+ movhi hi( fred ), r0, r1
+ movea lo( fred ), r1, r1
+
+ will store 0 in the value fields for the MOVHI and MOVEA instructions
+ and addend will be the address of fred, but for these instructions:
+
+ movhi hi( fred + 0x123456), r0, r1
+ movea lo( fred + 0x123456), r1, r1
+
+ the value stored in the MOVHI instruction will be 0x12 and the value
+ stored in the MOVEA instruction will be 0x3456. If however the
+ instructions were:
+
+ movhi hi( fred + 0x10ffff), r0, r1
+ movea lo( fred + 0x10ffff), r1, r1
+
+ then the value stored in the MOVHI instruction would be 0x11 (not
+ 0x10) and the value stored in the MOVEA instruction would be 0xffff.
+ Thus (assuming for the moment that the addend is 0), at run time the
+ MOVHI instruction loads 0x110000 into r1, then the MOVEA instruction
+ adds 0xffffffff (sign extension!) producing 0x10ffff. Similarly if
+ the instructions were:
+
+ movhi hi( fred - 1), r0, r1
+ movea lo( fred - 1), r1, r1
+
+ then 0 is stored in the MOVHI instruction and -1 is stored in the
+ MOVEA instruction.
+
+ Overflow can occur if the addition of the value stored in the
+ instruction plus the addend sets the 15th bit when before it was clear.
+ This is because the 15th bit will be sign extended into the high part,
+ thus reducing its value by one, but since the 15th bit was originally
+ clear, the assembler will not have added 1 to the previous HI16S reloc
+ to compensate for this effect. For example:
+
+ movhi hi( fred + 0x123456), r0, r1
+ movea lo( fred + 0x123456), r1, r1
+
+ The value stored in HI16S reloc is 0x12, the value stored in the LO16
+ reloc is 0x3456. If we assume that the address of fred is 0x00007000
+ then the relocations become:
+
+ HI16S: 0x0012 + (0x00007000 >> 16) = 0x12
+ LO16: 0x3456 + (0x00007000 & 0xffff) = 0xa456
+
+ but when the instructions are executed, the MOVEA instruction's value
+ is signed extended, so the sum becomes:
+
+ 0x00120000
+ + 0xffffa456
+ ------------
+ 0x0011a456 but 'fred + 0x123456' = 0x0012a456
+
+ Note that if the 15th bit was set in the value stored in the LO16
+ reloc, then we do not have to do anything:
+
+ movhi hi( fred + 0x10ffff), r0, r1
+ movea lo( fred + 0x10ffff), r1, r1
+
+ HI16S: 0x0011 + (0x00007000 >> 16) = 0x11
+ LO16: 0xffff + (0x00007000 & 0xffff) = 0x6fff
+
+ 0x00110000
+ + 0x00006fff
+ ------------
+ 0x00116fff = fred + 0x10ffff = 0x7000 + 0x10ffff
+
+ Overflow can also occur if the computation carries into the 16th bit
+ and it also results in the 15th bit having the same value as the 15th
+ bit of the original value. What happens is that the HI16S reloc
+ will have already examined the 15th bit of the original value and
+ added 1 to the high part if the bit is set. This compensates for the
+ sign extension of 15th bit of the result of the computation. But now
+ there is a carry into the 16th bit, and this has not been allowed for.
+
+ So, for example if fred is at address 0xf000:
+
+ movhi hi( fred + 0xffff), r0, r1 [bit 15 of the offset is set]
+ movea lo( fred + 0xffff), r1, r1
+
+ HI16S: 0x0001 + (0x0000f000 >> 16) = 0x0001
+ LO16: 0xffff + (0x0000f000 & 0xffff) = 0xefff (carry into bit 16 is lost)
+
+ 0x00010000
+ + 0xffffefff
+ ------------
+ 0x0000efff but 'fred + 0xffff' = 0x0001efff
+
+ Similarly, if the 15th bit remains clear, but overflow occurs into
+ the 16th bit then (assuming the address of fred is 0xf000):
+
+ movhi hi( fred + 0x7000), r0, r1 [bit 15 of the offset is clear]
+ movea lo( fred + 0x7000), r1, r1
+
+ HI16S: 0x0000 + (0x0000f000 >> 16) = 0x0000
+ LO16: 0x7000 + (0x0000f000 & 0xffff) = 0x6fff (carry into bit 16 is lost)
+
+ 0x00000000
+ + 0x00006fff
+ ------------
+ 0x00006fff but 'fred + 0x7000' = 0x00016fff
+
+ Note - there is no need to change anything if a carry occurs, and the
+ 15th bit changes its value from being set to being clear, as the HI16S
+ reloc will have already added in 1 to the high part for us:
+
+ movhi hi( fred + 0xffff), r0, r1 [bit 15 of the offset is set]
+ movea lo( fred + 0xffff), r1, r1
+
+ HI16S: 0x0001 + (0x00007000 >> 16)
+ LO16: 0xffff + (0x00007000 & 0xffff) = 0x6fff (carry into bit 16 is lost)
+
+ 0x00010000
+ + 0x00006fff (bit 15 not set, so the top half is zero)
+ ------------
+ 0x00016fff which is right (assuming that fred is at 0x7000)
+
+ but if the 15th bit goes from being clear to being set, then we must
+ once again handle overflow:
+
+ movhi hi( fred + 0x7000), r0, r1 [bit 15 of the offset is clear]
+ movea lo( fred + 0x7000), r1, r1
+
+ HI16S: 0x0000 + (0x0000ffff >> 16)
+ LO16: 0x7000 + (0x0000ffff & 0xffff) = 0x6fff (carry into bit 16)
+
+ 0x00000000
+ + 0x00006fff (bit 15 not set, so the top half is zero)
+ ------------
+ 0x00006fff which is wrong (assuming that fred is at 0xffff). */
+
+static bfd_boolean
+v850_elf_perform_lo16_relocation (bfd *abfd, unsigned long *insn,
+ unsigned long addend)
+{
+#define BIT15_SET(x) ((x) & 0x8000)
+#define OVERFLOWS(a,i) ((((a) & 0xffff) + (i)) > 0xffff)
+ if ((BIT15_SET (*insn + addend) && ! BIT15_SET (addend))
+ || (OVERFLOWS (addend, *insn)
+ && ((! BIT15_SET (*insn)) || (BIT15_SET (addend)))))
+ {
+ bfd_boolean already_updated;
+ bfd_byte *hi16s_address = find_remembered_hi16s_reloc
+ (addend, & already_updated);
+
+ /* Amend the matching HI16_S relocation. */
+ if (hi16s_address != NULL)
+ {
+ if (! already_updated)
+ {
+ unsigned long hi_insn = bfd_get_16 (abfd, hi16s_address);
+ hi_insn += 1;
+ bfd_put_16 (abfd, hi_insn, hi16s_address);
+ }
+ }
+ else
+ {
+ fprintf (stderr, _("FAILED to find previous HI16 reloc\n"));
+ return FALSE;
+ }
+ }
+#undef OVERFLOWS
+#undef BIT15_SET
+
+ /* Do not complain if value has top bit set, as this has been
+ anticipated. */
+ *insn = (*insn + addend) & 0xffff;
+ return TRUE;
+}
+
/* FIXME: The code here probably ought to be removed and the code in reloc.c
allowed to do its stuff instead. At least for most of the relocs, anyway. */
@@ -913,6 +1111,7 @@ v850_elf_perform_relocation (abfd, r_type, addend, address)
bfd_byte *address;
{
unsigned long insn;
+ unsigned long result;
bfd_signed_vma saddend = (bfd_signed_vma) addend;
switch (r_type)
@@ -972,183 +1171,10 @@ v850_elf_perform_relocation (abfd, r_type, addend, address)
break;
case R_V850_LO16:
- /* Calculate the sum of the value stored in the instruction and the
- addend and check for overflow from the low 16 bits into the high
- 16 bits. The assembler has already done some of this: If the
- value stored in the instruction has its 15th bit set, (counting
- from zero) then the assembler will have added 1 to the value
- stored in the associated HI16S reloc. So for example, these
- relocations:
-
- movhi hi( fred ), r0, r1
- movea lo( fred ), r1, r1
-
- will store 0 in the value fields for the MOVHI and MOVEA instructions
- and addend will be the address of fred, but for these instructions:
-
- movhi hi( fred + 0x123456), r0, r1
- movea lo( fred + 0x123456), r1, r1
-
- the value stored in the MOVHI instruction will be 0x12 and the value
- stored in the MOVEA instruction will be 0x3456. If however the
- instructions were:
-
- movhi hi( fred + 0x10ffff), r0, r1
- movea lo( fred + 0x10ffff), r1, r1
-
- then the value stored in the MOVHI instruction would be 0x11 (not
- 0x10) and the value stored in the MOVEA instruction would be 0xffff.
- Thus (assuming for the moment that the addend is 0), at run time the
- MOVHI instruction loads 0x110000 into r1, then the MOVEA instruction
- adds 0xffffffff (sign extension!) producing 0x10ffff. Similarly if
- the instructions were:
-
- movhi hi( fred - 1), r0, r1
- movea lo( fred - 1), r1, r1
-
- then 0 is stored in the MOVHI instruction and -1 is stored in the
- MOVEA instruction.
-
- Overflow can occur if the addition of the value stored in the
- instruction plus the addend sets the 15th bit when before it was clear.
- This is because the 15th bit will be sign extended into the high part,
- thus reducing its value by one, but since the 15th bit was originally
- clear, the assembler will not have added 1 to the previous HI16S reloc
- to compensate for this effect. For example:
-
- movhi hi( fred + 0x123456), r0, r1
- movea lo( fred + 0x123456), r1, r1
-
- The value stored in HI16S reloc is 0x12, the value stored in the LO16
- reloc is 0x3456. If we assume that the address of fred is 0x00007000
- then the relocations become:
-
- HI16S: 0x0012 + (0x00007000 >> 16) = 0x12
- LO16: 0x3456 + (0x00007000 & 0xffff) = 0xa456
-
- but when the instructions are executed, the MOVEA instruction's value
- is signed extended, so the sum becomes:
-
- 0x00120000
- + 0xffffa456
- ------------
- 0x0011a456 but 'fred + 0x123456' = 0x0012a456
-
- Note that if the 15th bit was set in the value stored in the LO16
- reloc, then we do not have to do anything:
-
- movhi hi( fred + 0x10ffff), r0, r1
- movea lo( fred + 0x10ffff), r1, r1
-
- HI16S: 0x0011 + (0x00007000 >> 16) = 0x11
- LO16: 0xffff + (0x00007000 & 0xffff) = 0x6fff
-
- 0x00110000
- + 0x00006fff
- ------------
- 0x00116fff = fred + 0x10ffff = 0x7000 + 0x10ffff
-
- Overflow can also occur if the computation carries into the 16th bit
- and it also results in the 15th bit having the same value as the 15th
- bit of the original value. What happens is that the HI16S reloc
- will have already examined the 15th bit of the original value and
- added 1 to the high part if the bit is set. This compensates for the
- sign extension of 15th bit of the result of the computation. But now
- there is a carry into the 16th bit, and this has not been allowed for.
-
- So, for example if fred is at address 0xf000:
-
- movhi hi( fred + 0xffff), r0, r1 [bit 15 of the offset is set]
- movea lo( fred + 0xffff), r1, r1
-
- HI16S: 0x0001 + (0x0000f000 >> 16) = 0x0001
- LO16: 0xffff + (0x0000f000 & 0xffff) = 0xefff (carry into bit 16 is lost)
-
- 0x00010000
- + 0xffffefff
- ------------
- 0x0000efff but 'fred + 0xffff' = 0x0001efff
-
- Similarly, if the 15th bit remains clear, but overflow occurs into
- the 16th bit then (assuming the address of fred is 0xf000):
-
- movhi hi( fred + 0x7000), r0, r1 [bit 15 of the offset is clear]
- movea lo( fred + 0x7000), r1, r1
-
- HI16S: 0x0000 + (0x0000f000 >> 16) = 0x0000
- LO16: 0x7000 + (0x0000f000 & 0xffff) = 0x6fff (carry into bit 16 is lost)
-
- 0x00000000
- + 0x00006fff
- ------------
- 0x00006fff but 'fred + 0x7000' = 0x00016fff
-
- Note - there is no need to change anything if a carry occurs, and the
- 15th bit changes its value from being set to being clear, as the HI16S
- reloc will have already added in 1 to the high part for us:
-
- movhi hi( fred + 0xffff), r0, r1 [bit 15 of the offset is set]
- movea lo( fred + 0xffff), r1, r1
-
- HI16S: 0x0001 + (0x00007000 >> 16)
- LO16: 0xffff + (0x00007000 & 0xffff) = 0x6fff (carry into bit 16 is lost)
-
- 0x00010000
- + 0x00006fff (bit 15 not set, so the top half is zero)
- ------------
- 0x00016fff which is right (assuming that fred is at 0x7000)
-
- but if the 15th bit goes from being clear to being set, then we must
- once again handle overflow:
-
- movhi hi( fred + 0x7000), r0, r1 [bit 15 of the offset is clear]
- movea lo( fred + 0x7000), r1, r1
-
- HI16S: 0x0000 + (0x0000ffff >> 16)
- LO16: 0x7000 + (0x0000ffff & 0xffff) = 0x6fff (carry into bit 16)
-
- 0x00000000
- + 0x00006fff (bit 15 not set, so the top half is zero)
- ------------
- 0x00006fff which is wrong (assuming that fred is at 0xffff). */
- {
- long result;
-
- insn = bfd_get_16 (abfd, address);
- result = insn + addend;
-
-#define BIT15_SET(x) ((x) & 0x8000)
-#define OVERFLOWS(a,i) ((((a) & 0xffff) + (i)) > 0xffff)
-
- if ((BIT15_SET (result) && ! BIT15_SET (addend))
- || (OVERFLOWS (addend, insn)
- && ((! BIT15_SET (insn)) || (BIT15_SET (addend)))))
- {
- bfd_boolean already_updated;
- bfd_byte *hi16s_address = find_remembered_hi16s_reloc
- (addend, & already_updated);
-
- /* Amend the matching HI16_S relocation. */
- if (hi16s_address != NULL)
- {
- if (! already_updated)
- {
- insn = bfd_get_16 (abfd, hi16s_address);
- insn += 1;
- bfd_put_16 (abfd, (bfd_vma) insn, hi16s_address);
- }
- }
- else
- {
- fprintf (stderr, _("FAILED to find previous HI16 reloc\n"));
- return bfd_reloc_overflow;
- }
- }
-
- /* Do not complain if value has top bit set, as this has been anticipated. */
- insn = result & 0xffff;
- break;
- }
+ insn = bfd_get_16 (abfd, address);
+ if (! v850_elf_perform_lo16_relocation (abfd, &insn, addend))
+ return bfd_reloc_overflow;
+ break;
case R_V850_8:
addend += (char) bfd_get_8 (abfd, address);
@@ -1278,6 +1304,17 @@ v850_elf_perform_relocation (abfd, r_type, addend, address)
insn |= addend;
break;
+ case R_V850_LO16_SPLIT_OFFSET:
+ insn = bfd_get_32 (abfd, address);
+ result = ((insn & 0xfffe0000) >> 16) | ((insn & 0x20) >> 5);
+ if (! v850_elf_perform_lo16_relocation (abfd, &result, addend))
+ return bfd_reloc_overflow;
+ insn = (((result << 16) & 0xfffe0000)
+ | ((result << 5) & 0x20)
+ | (insn & ~0xfffe0020));
+ bfd_put_32 (abfd, insn, address);
+ return bfd_reloc_ok;
+
case R_V850_ZDA_16_16_SPLIT_OFFSET:
case R_V850_SDA_16_16_SPLIT_OFFSET:
insn = bfd_get_32 (abfd, address);
@@ -1492,6 +1529,7 @@ v850_elf_final_link_relocate (howto, input_bfd, output_bfd,
case R_V850_HI16_S:
case R_V850_HI16:
case R_V850_LO16:
+ case R_V850_LO16_SPLIT_OFFSET:
case R_V850_16:
case R_V850_ABS32:
case R_V850_8: