The fscale implementation uses floatx80_scalbn for the final scaling
operation. floatx80_scalbn ends up rounding the result using the
dynamic rounding precision configured for the FPU. But only a limited
set of x87 floating-point instructions are supposed to respect the
dynamic rounding precision, and fscale is not in that set. Fix the
implementation to save and restore the rounding precision around the
call to floatx80_scalbn.
Backports commit c535d68755576bfa33be7aef7bd294a601f776e0 from qemu
The fscale implementation passes infinite exponents through to generic
code that rounds the exponent to a 32-bit integer before using
floatx80_scalbn. In round-to-nearest mode, and ignoring exceptions,
this works in many cases. But it fails to handle the special cases of
scaling 0 by a +Inf exponent or an infinity by a -Inf exponent, which
should produce a NaN, and because it produces an inexact result for
finite nonzero numbers being scaled, the result is sometimes incorrect
in other rounding modes. Add appropriate handling of infinite
exponents to produce a NaN or an appropriately signed exact zero or
infinity as a result
Backports commit c1c5fb8f9067c830e36830c2b82c0ec146c03d7b from qemu
The fscale implementation does not check for invalid encodings in the
exponent operand, thus treating them like INT_MIN (the value returned
for invalid encodings by floatx80_to_int32_round_to_zero). Fix it to
treat them similarly to signaling NaN exponents, thus generating a
quiet NaN result.
Backports commit b40eec96b26028b68c3594fbf34b6d6f029df26a from qemu
The implementation of the fscale instruction returns a NaN exponent
unchanged. Fix it to return a quiet NaN when the provided exponent is
a signaling NaN.
Backports commit 0d48b436327955c69e2eb53f88aba9aa1e0dbaa0 from qemu
The implementation of the fxtract instruction treats all nonzero
operands as normal numbers, so yielding incorrect results for invalid
formats, infinities, NaNs and subnormal and pseudo-denormal operands.
Implement appropriate handling of all those cases.
Backports commit c415f2c58296d86e9abb7e4a133111acf7031da3 from qemu
Detected by asm test suite failures in dav1d
(https://code.videolan.org/videolan/dav1d). Can be reproduced by
`qemu-x86_64 -cpu core2duo ./tests/checkasm --test=mc_8bpc 1659890620`.
Backports commit 2dfbea1a872727fb747ca6adf2390e09956cdc6e from qemu
The miscellaneous control instructions are mutually exclusive
within the t32 decode sub-group.
Backports commit d6084fba47bb9aef79775c1102d4b647eb58c365 from qemu
Includes multiple changes by Richard Henderson as follows:
- Use proper varargs to print the arguments. (2fd51b19c9)
- Rename MultiPattern to IncMultiPattern (040145c4f8)
- Split out MultiPattern from IncMultiPattern (df63044d02)
- Allow group covering the entire insn space (b44b3449a0)
- Move semantic propagation into classes (08561fc128)
- Implement non-overlapping groups (067e8b0f45)
- Drop check for less than 2 patterns in a group (fe079aa13d)
Convert the insns in the one-register-and-immediate group to decodetree.
In the new decode, our asimd_imm_const() function returns a 64-bit value
rather than a 32-bit one, which means we don't need to treat cmode=14 op=1
as a special case in the decoder (it is the only encoding where the two
halves of the 64-bit value are different).
Backports commit 2c35a39eda0b16c2ed85c94cec204bf5efb97812 from qemu
Convert the VCVT fixed-point conversion operations in the
Neon 2-regs-and-shift group to decodetree.
Backports commit 3da26f11711caeaa18318b6afa14dfb81d7650ab from qemu
Convert the VSHLL and VMOVL insns from the 2-reg-shift group
to decodetree. Since the loop always has two passes, we unroll
it to avoid the awkward reassignment of one TCGv to another.
Backports commit 968bf842742a5ffbb0041cb31089e61a9f7a833d from qemu
Convert the VQSHLU and QVSHL 2-reg-shift insns to decodetree.
These are the last of the simple shift-by-immediate insns.
Backports commit 37bfce81b10450071193c8495a07f182ec652e2a from qemu
Convert the VSHR 2-reg-shift insns to decodetree.
Note that unlike the legacy decoder, we present the right shift
amount to the trans_ function as a positive integer.
Backports commit 66432d6b8294e3508218b360acfdf7c244eea993 from qemu
Convert the VSHL and VSLI insns from the Neon 2-registers-and-a-shift
group to decodetree.
Backports commit d3c8c736f8b4bdd02831076286b1788232f46ced from qemu
Rather than passing an opcode to a helper, fully decode the
operation at translate time. Use clear_tail_16 to zap the
balance of the SVE register with the AdvSIMD write.
Backports commit 43fa36c96c24349145497adc1b451f9caf74e344 from qemu
Rather than passing an opcode to a helper, fully decode the
operation at translate time. Use clear_tail_16 to zap the
balance of the SVE register with the AdvSIMD write.
Backports commit afc8b7d32668547308bdd654a63cf5228936e0ba from qemu
Do not yet convert the helpers to loop over opr_sz, but the
descriptor allows the vector tail to be cleared. Which fixes
an existing bug vs SVE.
Backports commit effa992f153f5e7ab97ab843b565690748c5b402 from qemu
Do not yet convert the helpers to loop over opr_sz, but the
descriptor allows the vector tail to be cleared. Which fixes
an existing bug vs SVE.
Backports commit aaffebd6d3135b8aed7e61932af53b004d261579 from qemu
With this conversion, we will be able to use the same helpers
with sve. This also fixes a bug in which we failed to clear
the high bits of the SVE register after an AdvSIMD operation.
Backports commit 1738860d7e60dec5dbeba17f8b44d31aae3accac from qemu
With this conversion, we will be able to use the same helpers
with sve. In particular, pass 3 vector parameters for the
3-operand operations; for advsimd the destination register
is also an input.
This also fixes a bug in which we failed to clear the high bits
of the SVE register after an AdvSIMD operation.
Backports commit a04b68e1d4c4f0cd5cd7542697b1b230b84532f5 from qemu
The RISC-V ISA spec version 1.09.1 has been deprecated in QEMU since
4.1. It's not commonly used so let's remove support for it.
Backports commit 1a9540d1f1a9c5022d9273d0244e5809679dd33b from qemu
If the output of the move is dead, then the last use is in
the store. If we propagate the input to the store, then we
can remove the move opcode entirely.
Backports commit 61f15c487fc2aea14f6b0e52c459ae8b7d252a65 from qemu
For immediates, we must continue the special casing of 8-bit
elements. The other element sizes and shift types are trivially
implemented with shifts.
Backports commit 885b1706df6f0211a22e120fac910fb3abf3e733 from qemu
No host backend support yet, but the interfaces for rotls
are in place. Only implement left-rotate for now, as the
only known use of vector rotate by scalar is s390x, so any
right-rotate would be unused and untestable.
Backports commit 23850a74afb641102325b4b7f74071d929fc4594 from qemu
We do not reflect this expansion in tcg_can_emit_vecop_list,
so it is unused and unusable. However, we actually perform
the same expansion in do_gvec_shifts, so it is also unneeded.
Backports commit 3d5bb2ea5cc9ed54f65a6929a6e6baa01cabd98b from qemu
No host backend support yet, but the interfaces for rotlv
and rotrv are in place.
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
---
v3: Drop the generic expansion from rot to shift; we can do better
for each backend, and then this code becomes unused.
Backports commit 5d0ceda902915e3f0e21c39d142c92c4e97c3ebb from qemu
No host backend support yet, but the interfaces for rotli
are in place. Canonicalize immediate rotate to the left,
based on a survey of architectures, but provide both left
and right shift interfaces to the translators.
Backports commit b0f7e7444c03da17e41bf327c8aea590104a28ab from qemu
Example provided in the launchpad bug fails with:
qemu: uncaught target signal 4 (Illegal instruction) - core dumped
Illegal instruction (core dumped)
It appears fetoxm1 is not implemented:
IN: expm1f
0x800005cc: fetoxm1x %fp2,%fp0
Disassembler disagrees with translator over instruction decoding
Please report this to qemu-devel@nongnu.org
(gdb) x/2hx 0x800005cc
0x800005cc: 0xf200 0x0808
This patch adds the instruction.
Backports commit 250b1da35d579f42319af234f36207902ca4baa4 from qemu
Traditionally, MIPS use 4KB page size, but Loongson prefer 16KB page
size in system emulator. So, let's define TARGET_PAGE_BITS_VARY and
TARGET_PAGE_BITS_MIN to support variable page size.
Backports commit ee3863b9d414f0b4a59a88f2a79b496a99d4f6dd from qemu
Using the MSR instruction to write to CPSR.E is deprecated, but it is
required to work from any mode including unprivileged code. We were
incorrectly forbidding usermode code from writing it because
CPSR_USER did not include the CPSR_E bit.
We use CPSR_USER in only three places:
* as the mask of what to allow userspace MSR to write to CPSR
* when deciding what bits a linux-user signal-return should be
able to write from the sigcontext structure
* in target_user_copy_regs() when we set up the initial
registers for the linux-user process
In the first two cases not being able to update CPSR.E is a bug, and
in the third case it doesn't matter because CPSR.E is always 0 there.
So we can fix both bugs by adding CPSR_E to CPSR_USER.
Because the cpsr_write() in restore_sigcontext() is now changing
a CPSR bit which is cached in hflags, we need to add an
arm_rebuild_hflags() call there; the callsite in
target_user_copy_regs() was already rebuilding hflags for other
reasons.
(The recommended way to change CPSR.E is to use the 'SETEND'
instruction, which we do correctly allow from usermode code.)
Backports commit 268b1b3dfbb92a9348406f728a33f39e3d8dcd8a from qemu
Do not explicitly store zero to the NEON high part
when we can pass !is_q to clear_vec_high.
Backports commit e1f778596ebfa8782276f4dd4651f2b285d734ff from qemu
The 8-byte store for the end a !is_q operation can be
merged with the other stores. Use a no-op vector move
to trigger the expand_clr portion of tcg_gen_gvec_mov.
Backports commit 5c27392dd08bd8534893abf25ef501f1bd8680fe from qemu
Replace the floatx80 compare specializations with inline functions
that call the standard floatx80_compare{,_quiet} functions.
Use bool as the return type.
Backports commit c6baf65000f826a713e8d9b5b35e617b0ca9ab5d from qemu
Replace the float128 compare specializations with inline functions
that call the standard float128_compare{,_quiet} functions.
Use bool as the return type.
Backports commit b7b1ac684fea49c6bfe1ad8b706aed7b09116d15 from qemu
Replace the float64 compare specializations with inline functions
that call the standard float64_compare{,_quiet} functions.
Use bool as the return type.
Backports commit 0673ecdf6cb2b1445a85283db8cbacb251c46516 from qemu
Replace the float32 compare specializations with inline functions
that call the standard float32_compare{,_quiet} functions.
Use bool as the return type.
Backports commit 5da2d2d8e53d80e92a61720ea995c86b33cbf25d from qemu
Give the previously unnamed enum a typedef name. Use it in the
prototypes of compare functions. Use it to hold the results
of the compare functions.
Backports commit 71bfd65c5fcd72f8af2735905415c7ce4220f6dc from qemu
Give the previously unnamed enum a typedef name. Use the packed
attribute so that we do not affect the layout of the float_status
struct. Use it in the prototypes of relevant functions.
Adjust switch statements as necessary to avoid compiler warnings.
Backports commit 3dede407cc61b64997f0c30f6dbf4df09949abc9 from qemu
Slightly tidies the usage within softfloat.c and the
representation in float_status.
Backports commit a828b373bdabc7e53d1e218e3fc76f85b6674688 from qemu
The existing f{32,64}_addsub_post test, which checks for zero
inputs, is identical to f{32,64}_mul_fast_test. Which means
we can eliminate the fast_test/fast_op hooks in favor of
reusing the same post hook.
This means we have one fewer test along the fast path for multiply.
Backports commit b240c9c497b9880ac0ba29465907d5ebecd48083 from qemu
The softfloat function floatx80_round_to_int incorrectly handles the
case of a pseudo-denormal where only the high bit of the significand
is set, ignoring that bit (treating the number as an exact zero)
rather than treating the number as an alternative representation of
+/- 2^-16382 (which may round to +/- 1 depending on the rounding mode)
as hardware does. Fix this check (simplifying the code in the
process).
Backports commit 9ecaf5ccec13ff2e8fe1e72f6e0f3367d2169c1c from qemu
