Commit Graph

237 Commits

Author SHA1 Message Date
Leon Alrae
6489dd250a target-mips: ll and lld cause AdEL exception for unaligned address
Signed-off-by: Leon Alrae <leon.alrae@imgtec.com>
Reviewed-by: Maciej W. Rozycki <macro@linux-mips.org>
2015-02-13 14:11:29 +00:00
Peter Maydell
1535300119 target-mips: Don't use _raw load/store accessors
Use cpu_*_data instead of the direct *_raw load/store accessors.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <rth@twiddle.net>
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Message-id: 1421334118-3287-9-git-send-email-peter.maydell@linaro.org
2015-01-20 15:19:33 +00:00
Maciej W. Rozycki
bb962386b8 target-mips: Add missing calls to synchronise SoftFloat status
Add missing calls to synchronise the SoftFloat status with the CP1.FSCR:

+ for the rounding and flush-to-zero modes upon processor reset,

+ for the flush-to-zero mode on FSCR updates through the GDB stub.

Refactor code accordingly and remove the redundant RESTORE_ROUNDING_MODE
macro.

Signed-off-by: Thomas Schwinge <thomas@codesourcery.com>
Signed-off-by: Maciej W. Rozycki <macro@codesourcery.com>
Reviewed-by: Leon Alrae <leon.alrae@imgtec.com>
Signed-off-by: Leon Alrae <leon.alrae@imgtec.com>
2014-12-16 12:45:20 +00:00
Maciej W. Rozycki
1d725ae952 target-mips: Also apply the CP0.Status mask to MTTC0
Make CP0.Status writes made with the MTTC0 instruction respect this
register's mask just like all the other places.  Also preserve the
current values of masked out bits.

Signed-off-by: Maciej W. Rozycki <macro@codesourcery.com>
Reviewed-by: Leon Alrae <leon.alrae@imgtec.com>
Signed-off-by: Leon Alrae <leon.alrae@imgtec.com>
2014-12-16 12:45:20 +00:00
Maciej W. Rozycki
90f12d735d target-mips: Fix CP0.Config3.ISAOnExc write accesses
Fix CP0.Config3.ISAOnExc write accesses on microMIPS processors.  This
bit is mandatory for any processor that implements the microMIPS
instruction set.  This bit is r/w for processors that implement both the
standard MIPS and the microMIPS instruction set.  This bit is r/o and
hardwired to 1 if only the microMIPS instruction set is implemented.

There is no other bit ever writable in CP0.Config3 so defining a
corresponding `CP0_Config3_rw_bitmask' member in `CPUMIPSState' is I
think an overkill.  Therefore make the ability to write the bit rely on
the presence of ASE_MICROMIPS set in the instruction flags.

The read-only case of the microMIPS instruction set being implemented
only can be added when we add support for such a configuration.  We do
not currently have such support, we have no instruction flag that would
control the presence of the standard MIPS instruction set nor any
associated code in instruction decoding.

This change is needed to boot a microMIPS Linux kernel successfully,
otherwise it hangs early on as interrupts are enabled and then the
exception handler invoked loops as its first instruction is interpreted
in the wrong execution mode and triggers another exception right away.
And then over and over again.

We already check the current setting of the CP0.Config3.ISAOnExc in
`set_hflags_for_handler' to set the ISA bit correctly on the exception
handler entry so it is the ability to set it that is missing only.

Signed-off-by: Maciej W. Rozycki <macro@codesourcery.com>
Reviewed-by: Leon Alrae <leon.alrae@imgtec.com>
Signed-off-by: Leon Alrae <leon.alrae@imgtec.com>
2014-12-16 12:45:20 +00:00
Maciej W. Rozycki
81a423e6c6 target-mips: Correct the writes to Status and Cause registers via gdbstub
Make writes to CP0.Status and CP0.Cause have the same effect as
executing corresponding MTC0 instructions would in Kernel Mode.  Also
ignore writes in the user emulation mode.

Currently for requests from the GDB stub we write all the bits across
both registers, ignoring any read-only locations, and do not synchronise
the environment to evaluate side effects.  We also write these registers
in the user emulation mode even though a real kernel presents them as
read only.

Signed-off-by: Maciej W. Rozycki <macro@codesourcery.com>
Signed-off-by: Leon Alrae <leon.alrae@imgtec.com>
2014-12-16 12:45:19 +00:00
Maciej W. Rozycki
f88f79ec9d target-mips: Correct the handling of writes to CP0.Status for MIPSr6
Correct these issues with the handling of CP0.Status for MIPSr6:

* only ignore the bit pattern of 0b11 on writes to CP0.Status.KSU, that
  is for processors that do implement Supervisor Mode, let the bit
  pattern be written to CP0.Status.UM:R0 freely (of course the value
  written to read-only CP0.Status.R0 will be discarded anyway); this is
  in accordance to the relevant architecture specification[1],

* check the newly written pattern rather than the current contents of
  CP0.Status for the KSU bits being 0b11,

* use meaningful macro names to refer to CP0.Status bits rather than
  magic numbers.

References:

[1] "MIPS Architecture For Programmers, Volume III: MIPS64 / microMIPS64
    Privileged Resource Architecture", MIPS Technologies, Inc., Document
    Number: MD00091, Revision 6.00, March 31, 2014, Table 9.45 "Status
    Register Field Descriptions", pp. 210-211.

Signed-off-by: Maciej W. Rozycki <macro@codesourcery.com>
Reviewed-by: Leon Alrae <leon.alrae@imgtec.com>
Signed-off-by: Leon Alrae <leon.alrae@imgtec.com>
2014-12-16 12:45:19 +00:00
Maciej W. Rozycki
8fc605b8aa target-mips: Restore the order of helpers
Restore the order of helpers that used to be: unary operations (generic,
then MIPS-specific), binary operations (generic, then MIPS-specific),
compare operations.  At one point FMA operations were inserted at a
random place in the file, disregarding the preexisting order, and later
on even more operations sprinkled across the file.  Revert the mess by
moving FMA operations to a new ternary class inserted after the binary
class and move the misplaced unary and binary operations to where they
belong.

Signed-off-by: Maciej W. Rozycki <macro@codesourcery.com>
Signed-off-by: Leon Alrae <leon.alrae@imgtec.com>
2014-12-16 12:45:19 +00:00
Maciej W. Rozycki
51fdea945a target-mips: Remove unused `FLOAT_OP' macro
Remove the `FLOAT_OP' macro, unused since commit
b6d96beda3 [Use temporary registers for
the MIPS FPU emulation.].

Signed-off-by: Maciej W. Rozycki <macro@codesourcery.com>
Signed-off-by: Leon Alrae <leon.alrae@imgtec.com>
2014-12-16 12:45:19 +00:00
Maciej W. Rozycki
2b09f94cdb target-mips: Make `helper_float_cvtw_s' consistent with the remaining helpers
Move the call to `update_fcr31' in `helper_float_cvtw_s' after the
exception flag check, for consistency with the remaining helpers that do
it last too.

Signed-off-by: Maciej W. Rozycki <macro@codesourcery.com>
Signed-off-by: Leon Alrae <leon.alrae@imgtec.com>
2014-12-16 12:45:19 +00:00
Yongbok Kim
f7685877f5 target-mips: add MSA MI10 format instructions
add MSA MI10 format instructions
update LSA and DLSA for MSA

add 16, 64 bit load and store

Signed-off-by: Yongbok Kim <yongbok.kim@imgtec.com>
Signed-off-by: Leon Alrae <leon.alrae@imgtec.com>
2014-11-03 11:48:35 +00:00
Yongbok Kim
b7651e9521 target-mips: remove duplicated mips/ieee mapping function
Remove the duplicated ieee_rm in gdbstub.c.
Make the other ieee_rm and ieee_ex_to_mips available to other files.

Reviewed-by: James Hogan <james.hogan@imgtec.com>
Reviewed-by: Leon Alrae <leon.alrae@imgtec.com>
Signed-off-by: Yongbok Kim <yongbok.kim@imgtec.com>
Signed-off-by: Leon Alrae <leon.alrae@imgtec.com>
2014-11-03 11:48:35 +00:00
Yongbok Kim
e97a391d20 target-mips: add MSA defines and data structure
add defines and data structure for MIPS SIMD Architecture

Reviewed-by: James Hogan <james.hogan@imgtec.com>
Signed-off-by: Yongbok Kim <yongbok.kim@imgtec.com>
Signed-off-by: Leon Alrae <leon.alrae@imgtec.com>
2014-11-03 11:48:35 +00:00
Leon Alrae
ba801af429 target-mips: add restrictions for possible values in registers
In Release 6 not all the values are allowed to be written to a register.
If the value is not valid or unsupported then it should stay unchanged.

For pre-R6 the existing behaviour has been changed only for CP0_Index register
as the current implementation does not seem to be correct - it looks like it
tries to limit the input value but the limit is higher than the actual
number of tlb entries.

Signed-off-by: Leon Alrae <leon.alrae@imgtec.com>
Reviewed-by: Yongbok Kim <yongbok.kim@imgtec.com>
2014-11-03 11:48:34 +00:00
Leon Alrae
aea14095ea target-mips: add BadInstr and BadInstrP support
BadInstr Register (CP0 Register 8, Select 1)
The BadInstr register is a read-only register that capture the most recent
instruction which caused an exception.

BadInstrP Register (CP0 Register 8, Select 2)
The BadInstrP register contains the prior branch instruction, when the
faulting instruction is in a branch delay slot.

Using error_code to indicate whether AdEL or TLBL was triggered during
instruction fetch, in this case BadInstr is not updated as valid instruction
word is not available.

Signed-off-by: Leon Alrae <leon.alrae@imgtec.com>
Reviewed-by: Yongbok Kim <yongbok.kim@imgtec.com>
2014-11-03 11:48:34 +00:00
Leon Alrae
9456c2fbcd target-mips: add TLBINV support
For Standard TLB configuration (Config.MT=1):

TLBINV invalidates a set of TLB entries based on ASID. The virtual address is
ignored in the entry match. TLB entries which have their G bit set to 1 are not
modified.

TLBINVF causes all entries to be invalidated.

Single TLB entry can be marked as invalid on TLB entry write by having
EntryHi.EHINV set to 1.

Signed-off-by: Leon Alrae <leon.alrae@imgtec.com>
Reviewed-by: Yongbok Kim <yongbok.kim@imgtec.com>
2014-11-03 11:48:34 +00:00
Leon Alrae
7207c7f9d7 target-mips: update PageGrain and m{t,f}c0 EntryLo{0,1}
PageGrain needs rw bitmask which differs between MIPS architectures.
In pre-R6 if RIXI is supported, PageGrain.XIE and PageGrain.RIE are writeable,
whereas in R6 they are read-only 1.

On MIPS64 mtc0 instruction left shifts bits 31:30 for MIPS32 backward
compatiblity, therefore there are separate mtc0 and dmtc0 helpers.

Signed-off-by: Leon Alrae <leon.alrae@imgtec.com>
Reviewed-by: Yongbok Kim <yongbok.kim@imgtec.com>
2014-11-03 11:48:34 +00:00
Leon Alrae
2fb58b7374 target-mips: add RI and XI fields to TLB entry
In Revision 3 of the architecture, the RI and XI bits were added to the TLB
to enable more secure access of memory pages. These bits (along with the Dirty
bit) allow the implementation of read-only, write-only, no-execute access
policies for mapped pages.

Signed-off-by: Leon Alrae <leon.alrae@imgtec.com>
Reviewed-by: Yongbok Kim <yongbok.kim@imgtec.com>
2014-11-03 11:48:34 +00:00
Leon Alrae
74dda9876b target-mips: add ULL suffix in bitswap to avoid compiler warning
Signed-off-by: Leon Alrae <leon.alrae@imgtec.com>
Message-id: 1413982829-27225-1-git-send-email-leon.alrae@imgtec.com
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2014-10-24 14:07:51 +01:00
Peter Maydell
b808a1a812 target-mips/op_helper.c: Remove unused do_lbu() function
The do_lbu() function defined by the expansion of HELPER_LD() is
never used, so don't define it.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <rth@twiddle.net>
Signed-off-by: Leon Alrae <leon.alrae@imgtec.com>
2014-10-14 13:29:14 +01:00
Yongbok Kim
3f4938833c target-mips: add new Floating Point Comparison instructions
Signed-off-by: Yongbok Kim <yongbok.kim@imgtec.com>
Signed-off-by: Leon Alrae <leon.alrae@imgtec.com>
Reviewed-by: Aurelien Jarno <aurelien@aurel32.net>
2014-10-14 13:28:52 +01:00
Leon Alrae
e7f16abbc5 target-mips: add new Floating Point instructions
In terms of encoding MIPS32R6 MIN.fmt, MAX.fmt, MINA.fmt, MAXA.fmt replaced
MIPS-3D RECIP1, RECIP2, RSQRT1, RSQRT2 instructions.

In R6 all Floating Point instructions are supposed to be IEEE-2008 compliant
i.e. FIR.HAS2008 always 1. However, QEMU softfloat for MIPS has not been
updated yet.

Signed-off-by: Leon Alrae <leon.alrae@imgtec.com>
Reviewed-by: Yongbok Kim <yongbok.kim@imgtec.com>
2014-10-14 13:28:51 +01:00
Yongbok Kim
15eacb9b52 target-mips: add ALIGN, DALIGN, BITSWAP and DBITSWAP instructions
Signed-off-by: Yongbok Kim <yongbok.kim@imgtec.com>
Signed-off-by: Leon Alrae <leon.alrae@imgtec.com>
Reviewed-by: Aurelien Jarno <aurelien@aurel32.net>
2014-10-13 12:38:25 +01:00
James Hogan
eddedd546a target-mips: Ignore unassigned accesses with KVM
MIPS registers an unassigned access handler which raises a guest bus
error exception. However this causes QEMU to crash when KVM is enabled
as it isn't called from the main execution loop so longjmp() gets called
without a corresponding setjmp().

Until the KVM API can be updated to trigger a guest exception in
response to an MMIO exit, prevent the bus error exception being raised
from mips_cpu_unassigned_access() if KVM is enabled.

The check is at run time since the do_unassigned_access callback is
initialised before it is known whether KVM will be enabled.

The problem can be triggered with Malta emulation by making the guest
write to the reset region at physical address 0x1bf00000, since it is
marked read-only which is treated as unassigned for writes.

Signed-off-by: James Hogan <james.hogan@imgtec.com>
Reviewed-by: Aurelien Jarno <aurelien@aurel32.net>
Cc: Peter Maydell <peter.maydell@linaro.org>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Gleb Natapov <gleb@redhat.com>
Cc: Christoffer Dall <christoffer.dall@linaro.org>
Cc: Sanjay Lal <sanjayl@kymasys.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2014-08-07 15:09:48 +02:00
Petar Jovanovic
d279279e2b target-mips: implement UserLocal Register
From MIPS documentation (Volume III):

UserLocal Register (CP0 Register 4, Select 2)
Compliance Level: Recommended.

The UserLocal register is a read-write register that is not interpreted by
the hardware and conditionally readable via the RDHWR instruction.

This register only exists if the Config3-ULRI register field is set.

Privileged software may write this register with arbitrary information and
make it accessible to unprivileged software via register 29 (ULR) of the
RDHWR instruction. To do so, bit 29 of the HWREna register must be set to a
1 to enable unprivileged access to the register.

Signed-off-by: Petar Jovanovic <petar.jovanovic@imgtec.com>
Reviewed-by: Andreas Färber <afaerber@suse.de>
Reviewed-by: Aurelien Jarno <aurelien@aurel32.net>
Signed-off-by: Aurelien Jarno <aurelien@aurel32.net>
2014-06-18 18:10:47 +02:00
Paolo Bonzini
f08b617018 softmmu: introduce cpu_ldst.h
This will collect all load and store helpers soon.  For now
it is just a replacement for softmmu_exec.h, which this patch
stops including directly, but we also include it where this will
be necessary in order to simplify the next patch.

Reviewed-by: Richard Henderson <rth@twiddle.net>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2014-06-05 16:10:33 +02:00
Paolo Bonzini
0f590e749f softmmu: commonize helper definitions
They do not need to be in op_helper.c.  Because cputlb.c now includes
softmmu_template.h twice for each size, io_readX must be elided the
second time through.

Reviewed-by: Richard Henderson <rth@twiddle.net>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2014-06-05 16:10:33 +02:00
Paolo Bonzini
d94f0a8ecb softmmu: move ALIGNED_ONLY to cpu.h
Prepare for moving softmmu_header.h inclusion out of .c files

Reviewed-by: Richard Henderson <rth@twiddle.net>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2014-06-05 16:10:33 +02:00
Paolo Bonzini
93e22326d6 softmmu: make do_unaligned_access a method of CPU
We will reference it from more files in the next patch.  To avoid
ruining the small steps we're making towards multi-target, make
it a method of CPU rather than just a global.

Reviewed-by: Andreas Färber <afaerber@suse.de>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2014-06-05 16:10:31 +02:00
Richard Henderson
2ef6175aa7 tcg: Invert the inclusion of helper.h
Rather than include helper.h with N values of GEN_HELPER, include a
secondary file that sets up the macros to include helper.h.  This
minimizes the files that must be rebuilt when changing the macros
for file N.

Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Signed-off-by: Richard Henderson <rth@twiddle.net>
2014-05-28 09:33:54 -07:00
Peter Maydell
f45cb2f43f target-mips: Avoid shifting left into sign bit
Add U suffix to various places where we shift a 1 left by 31,
to avoid undefined behaviour.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Michael Tokarev <mjt@tls.msk.ru>
2014-03-27 19:22:49 +04:00
Andreas Färber
00c8cb0a36 cputlb: Change tlb_flush() argument to CPUState
Signed-off-by: Andreas Färber <afaerber@suse.de>
2014-03-13 19:52:47 +01:00
Andreas Färber
a47dddd734 exec: Change cpu_abort() argument to CPUState
Signed-off-by: Andreas Färber <afaerber@suse.de>
2014-03-13 19:52:28 +01:00
Andreas Färber
3f38f309b2 translate-all: Change cpu_restore_state() argument to CPUState
This lets us drop some local variables in tlb_fill() functions.

Signed-off-by: Andreas Färber <afaerber@suse.de>
2014-03-13 19:20:47 +01:00
Andreas Färber
5638d180d6 cpu-exec: Change cpu_loop_exit() argument to CPUState
Signed-off-by: Andreas Färber <afaerber@suse.de>
2014-03-13 19:20:47 +01:00
Andreas Färber
d5a11fefef exec: Change tlb_fill() argument to CPUState
Signed-off-by: Andreas Färber <afaerber@suse.de>
2014-03-13 19:20:47 +01:00
Andreas Färber
27103424c4 cpu: Move exception_index field from CPU_COMMON to CPUState
Signed-off-by: Andreas Färber <afaerber@suse.de>
2014-03-13 19:20:46 +01:00
Andreas Färber
7510454e3e cpu: Turn cpu_handle_mmu_fault() into a CPUClass hook
Note that while such functions may exist both for *-user and softmmu,
only *-user uses the CPUState hook, while softmmu reuses the prototype
for calling it directly.

Signed-off-by: Andreas Färber <afaerber@suse.de>
2014-03-13 19:20:46 +01:00
Petar Jovanovic
736d120af4 target-mips: add user-mode FR switch support for MIPS32r5
Description of UFR feature:

Required in MIPS32r5 if floating point is implemented and user-mode FR
switching is supported. The UFR register allows user-mode to clear StatusFR
by executing a CTC1 to UFR with GPR[0] as input, and read StatusFR by
executing a CFC1 to UFR.

helper_ctc1 has been extended with an additional parameter rt to check
requirements for UFR feature.
Definition of mips32r5-generic has been modified to include support for UFR.

Signed-off-by: Petar Jovanovic <petar.jovanovic@imgtec.com>
Reviewed-by: Eric Johnson <eric.johnson@imgtec.com>
2014-02-10 16:46:38 +01:00
Petar Jovanovic
b4dd99a363 target-mips: add support for CP0_Config5
Add CP0_Config5, define rw_bitmask and enable modifications.

Signed-off-by: Petar Jovanovic <petar.jovanovic@imgtec.com>
Reviewed-by: Eric Johnson <eric.johnson@imgtec.com>
2014-02-10 16:46:28 +01:00
Petar Jovanovic
b4160af160 target-mips: add support for CP0_Config4
Add CP0_Config4, define rw_bitmask.

Signed-off-by: Petar Jovanovic <petar.jovanovic@imgtec.com>
Reviewed-by: Eric Johnson <eric.johnson@imgtec.com>
2014-02-10 16:46:12 +01:00
Andreas Färber
bdc44640cb cpu: Use QTAILQ for CPU list
Introduce CPU_FOREACH(), CPU_FOREACH_SAFE() and CPU_NEXT() shorthand
macros.

Signed-off-by: Andreas Färber <afaerber@suse.de>
2013-09-03 12:25:55 +02:00
Stefan Weil
d2e46d59ca target-mips: Remove assignment to a variable which is never used
This assignment causes a compiler warning for compilations with the compiler
option -Wunused-but-set-variable (which is included with -Wextra).

Removing it allows using -Wextra for QEMU code without suppressing too many
extra warnings.

Signed-off-by: Stefan Weil <sw@weilnetz.de>
Signed-off-by: Aurelien Jarno <aurelien@aurel32.net>
2013-07-29 00:31:43 +02:00
Andreas Färber
182735efaf cpu: Make first_cpu and next_cpu CPUState
Move next_cpu from CPU_COMMON to CPUState.
Move first_cpu variable to qom/cpu.h.

gdbstub needs to use CPUState::env_ptr for now.
cpu_copy() no longer needs to save and restore cpu_next.

Acked-by: Paolo Bonzini <pbonzini@redhat.com>
[AF: Rebased, simplified cpu_copy()]
Signed-off-by: Andreas Färber <afaerber@suse.de>
2013-07-09 21:32:54 +02:00
Andreas Färber
c658b94f6e cpu: Turn cpu_unassigned_access() into a CPUState hook
Use it for all targets, but be careful not to pass invalid CPUState.
cpu_single_env can be NULL, e.g. on Xen.

Signed-off-by: Andreas Färber <afaerber@suse.de>
2013-06-28 13:25:13 +02:00
Andreas Färber
c3affe5670 cpu: Pass CPUState to cpu_interrupt()
Move it to qom/cpu.h to avoid issues with include order.

Change pc_acpi_smi_interrupt() opaque to X86CPU.

Signed-off-by: Andreas Färber <afaerber@suse.de>
2013-03-12 10:35:55 +01:00
Andreas Färber
d8ed887bdc exec: Pass CPUState to cpu_reset_interrupt()
Move it to qom/cpu.c to avoid build failures depending on include order
of cpu-qom.h and exec/cpu-all.h.

Change opaques of various ..._irq_handler() functions to the
appropriate CPU type to facilitate using cpu_reset_interrupt().

Fix Coding Style issues while at it (missing braces, indentation).

Signed-off-by: Andreas Färber <afaerber@suse.de>
2013-03-12 10:35:55 +01:00
Andreas Färber
259186a7d2 cpu: Move halted and interrupt_request fields to CPUState
Both fields are used in VMState, thus need to be moved together.
Explicitly zero them on reset since they were located before
breakpoints.

Pass PowerPCCPU to kvmppc_handle_halt().

Signed-off-by: Andreas Färber <afaerber@suse.de>
2013-03-12 10:35:55 +01:00
Richard Henderson
ce1dd5d1bb target-mips: Use mul[us]2 in [D]MULT[U] insns
Cc: Aurelien Jarno <aurelien@aurel32.net>
Signed-off-by: Richard Henderson <rth@twiddle.net>
Signed-off-by: Blue Swirl <blauwirbel@gmail.com>
2013-02-23 17:25:29 +00:00
Richard Sandiford
f54c35d1ea target-mips: Unfuse {,N}M{ADD,SUB}.fmt
Turn MADD.fmt, MSUB.fmt, NMADD.fmt and NMSUB.fmt from fused to unfused
operations, so that they behave in the same way as a separate multiplication
and addition.  The instructions were only fused in early MIPS IV processors.

Signed-off-by: Richard Sandiford <rdsandiford@googlemail.com>
Signed-off-by: Aurelien Jarno <aurelien@aurel32.net>
2013-01-31 23:42:02 +01:00