Commit Graph

511 Commits

Author SHA1 Message Date
Peter Maydell 06085d6a10 target/arm: Move vfp_{load, store}_reg{32, 64} to translate-vfp.c.inc
The functions vfp_load_reg32(), vfp_load_reg64(), vfp_store_reg32()
and vfp_store_reg64() are used only in translate-vfp.c.inc. Move
them to that file.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 20210430132740.10391-7-peter.maydell@linaro.org
2021-05-10 13:24:09 +01:00
Peter Maydell 73d2f5d2bb target/arm: Move gen_aa32 functions to translate-a32.h
Move the various gen_aa32* functions and macros out of translate.c
and into translate-a32.h.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 20210430132740.10391-6-peter.maydell@linaro.org
2021-05-10 13:24:09 +01:00
Peter Maydell 9a5071abbc target/arm: Split m-nocp trans functions into their own file
Currently the trans functions for m-nocp.decode all live in
translate-vfp.inc.c; move them out into their own translation unit,
translate-m-nocp.c.

The trans_* functions here are pure code motion with no changes.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 20210430132740.10391-5-peter.maydell@linaro.org
2021-05-10 13:24:09 +01:00
Peter Maydell 5ce389f2e7 target/arm: Make functions used by m-nocp global
We want to split out the .c.inc files which are currently included
into translate.c so they are separate compilation units.  To do this
we need to make some functions which are currently file-local to
translate.c have global scope; create a translate-a32.h paralleling
the existing translate-a64.h as a place for these declarations to
live, so that code moved into the new compilation units can call
them.

The functions made global here are those required by the
m-nocp.decode functions, except that I have converted the whole
family of {read,write}_neon_element* and also both the load_cpu and
store_cpu functions for consistency, even though m-nocp only wants a
few functions from each.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 20210430132740.10391-4-peter.maydell@linaro.org
2021-05-10 13:24:09 +01:00
Peter Maydell d9318a5f9c target/arm: Share unallocated_encoding() and gen_exception_insn()
The unallocated_encoding() function is the same in both
translate-a64.c and translate.c; make the translate.c function global
and drop the translate-a64.c version.  To do this we need to also
share gen_exception_insn(), which currently exists in two slightly
different versions for A32 and A64: merge those into a single
function that can work for both.

This will be useful for splitting up translate.c, which will require
unallocated_encoding() to no longer be file-local.  It's also
hopefully less confusing to have only one version of the function
rather than two.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 20210430132740.10391-3-peter.maydell@linaro.org
2021-05-10 13:24:09 +01:00
Peter Maydell b5aa664679 target/arm: Move constant expanders to translate.h
Some of the constant expanders defined in translate.c are generically
useful and will be used by the separate C files for VFP and Neon once
they are created; move the expander definitions to translate.h.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 20210430132740.10391-2-peter.maydell@linaro.org
2021-05-10 13:24:09 +01:00
Richard Henderson a8502b37f6 target/arm: Enforce alignment for VLDn (all lanes)
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 20210419202257.161730-23-richard.henderson@linaro.org
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2021-04-30 11:16:51 +01:00
Richard Henderson 2fd0800c68 target/arm: Enforce alignment for SRS
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 20210419202257.161730-20-richard.henderson@linaro.org
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2021-04-30 11:16:51 +01:00
Richard Henderson c0c7f66087 target/arm: Enforce alignment for RFE
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 20210419202257.161730-19-richard.henderson@linaro.org
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2021-04-30 11:16:51 +01:00
Richard Henderson 2e1f39e29b target/arm: Enforce alignment for LDM/STM
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 20210419202257.161730-18-richard.henderson@linaro.org
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2021-04-30 11:16:51 +01:00
Richard Henderson 824efdf525 target/arm: Enforce alignment for LDA/LDAH/STL/STLH
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 20210419202257.161730-17-richard.henderson@linaro.org
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2021-04-30 11:16:50 +01:00
Richard Henderson 4d753eb5fb target/arm: Enforce word alignment for LDRD/STRD
Buglink: https://bugs.launchpad.net/qemu/+bug/1905356
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 20210419202257.161730-16-richard.henderson@linaro.org
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2021-04-30 11:16:50 +01:00
Richard Henderson abe66294e1 target/arm: Adjust gen_aa32_{ld, st}_i64 for align+endianness
Adjust the interface to match what has been done to the
TCGv_i32 load/store functions.

This is less obvious, because at present the only user of
these functions, trans_VLDST_multiple, also wants to manipulate
the endianness to speed up loading multiple bytes.  Thus we
retain an "internal" interface which is identical to the
current gen_aa32_{ld,st}_i64 interface.

The "new" interface will gain users as we remove the legacy
interfaces, gen_aa32_ld64 and gen_aa32_st64.

Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 20210419202257.161730-15-richard.henderson@linaro.org
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2021-04-30 11:16:50 +01:00
Richard Henderson 9565ac4cc7 target/arm: Fix SCTLR_B test for TCGv_i64 load/store
Just because operating on a TCGv_i64 temporary does not
mean that we're performing a 64-bit operation.  Restrict
the frobbing to actual 64-bit operations.

This bug is not currently visible because all current
users of these two functions always pass MO_64.

Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 20210419202257.161730-14-richard.henderson@linaro.org
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2021-04-30 11:16:50 +01:00
Richard Henderson 37bf7a055f target/arm: Merge gen_aa32_frob64 into gen_aa32_ld_i64
This is the only caller.  Adjust some commentary to talk
about SCTLR_B instead of the vanishing function.

Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 20210419202257.161730-13-richard.henderson@linaro.org
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2021-04-30 11:16:50 +01:00
Richard Henderson 9d486b40e8 target/arm: Adjust gen_aa32_{ld, st}_i32 for align+endianness
Create a finalize_memop function that computes alignment and
endianness and returns the final MemOp for the operation.

Split out gen_aa32_{ld,st}_internal_i32 which bypasses any special
handling of endianness or alignment.  Adjust gen_aa32_{ld,st}_i32
so that s->be_data is not added by the callers.

Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 20210419202257.161730-12-richard.henderson@linaro.org
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2021-04-30 11:16:50 +01:00
Richard Henderson 4479ec30c9 target/arm: Add ALIGN_MEM to TBFLAG_ANY
Use this to signal when memory access alignment is required.
This value comes from the CCR register for M-profile, and
from the SCTLR register for A-profile.

Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 20210419202257.161730-11-richard.henderson@linaro.org
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2021-04-30 11:16:50 +01:00
Richard Henderson 3902bfc6f0 target/arm: Introduce CPUARMTBFlags
In preparation for splitting tb->flags across multiple
fields, introduce a structure to hold the value(s).
So far this only migrates the one uint32_t and fixes
all of the places that require adjustment to match.

Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 20210419202257.161730-6-richard.henderson@linaro.org
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2021-04-30 11:16:50 +01:00
Richard Henderson a729a46b05 target/arm: Add wrapper macros for accessing tbflags
We're about to split tbflags into two parts.  These macros
will ensure that the correct part is used with the correct
set of bits.

Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 20210419202257.161730-5-richard.henderson@linaro.org
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2021-04-30 11:16:50 +01:00
Richard Henderson ae6eb1e9b3 target/arm: Rename TBFLAG_ANY, PSTATE_SS
We're about to rearrange the macro expansion surrounding tbflags,
and this field name will be expanded using the bit definition of
the same name, resulting in a token pasting error.

So PSTATE_SS -> PSTATE__SS in the uses, and document it.

Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 20210419202257.161730-4-richard.henderson@linaro.org
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2021-04-30 11:16:50 +01:00
Richard Henderson 6a01eab7d8 target/arm: Rename TBFLAG_A32, SCTLR_B
We're about to rearrange the macro expansion surrounding tbflags,
and this field name will be expanded using the bit definition of
the same name, resulting in a token pasting error.

So SCTLR_B -> SCTLR__B in the 3 uses, and document it.

Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 20210419202257.161730-3-richard.henderson@linaro.org
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2021-04-30 11:16:49 +01:00
Peter Maydell 8196fe9d83 target/arm: Make Thumb store insns UNDEF for Rn==1111
The Arm ARM specifies that for Thumb encodings of the various plain
store insns, if the Rn field is 1111 then we must UNDEF.  This is
different from the Arm encodings, where this case is either
UNPREDICTABLE or has well-defined behaviour.  The exclusive stores,
store-release and STRD do not have this UNDEF case for any encoding.

Enforce the UNDEF for this case in the Thumb plain store insns.

Fixes: https://bugs.launchpad.net/qemu/+bug/1922887
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 20210408162402.5822-1-peter.maydell@linaro.org
2021-04-30 11:16:49 +01:00
Alex Bennée c57b27ea89 target/arm: drop CF_LAST_IO/dc->condjump check
This is a left over erroneous check from the days front-ends handled
io start/end themselves. Regardless just because IO could be performed
on the last instruction doesn't obligate the front end to do so.

This fixes an abort faced by the aspeed execute-in-place support which
will necessarily trigger this state (even before the one-shot
CF_LAST_IO fix). The test still seems to hang once it attempts to boot
the Linux kernel but I suspect this is an unrelated issue with icount
and the timer handling code.

The original intention of the cpu_abort (added in commit 2e70f6efa8
when the icount stuff was first added) seems to have been to act as
an assert() to catch an unhandled corner case where the generated code
would be something like:
    conditional branch to condlabel if its cc failed
    implementation of the insn (a conditional branch or trap)
    code emitted by gen_io_end()
 condlabel:
    gen_goto_tb or equivalent thing to go to next insn

At runtime the cc-failed case would skip over the code emitted by
gen_io_end(), leaving the can_do_io flag incorrectly set.

In commit ba3e792669 we switched to an implementation which
always clears can_do_io at the start of the following TB instead
of trying to clear it at the end of a TB that did IO. So the corner
case that this cpu_abort() was trying to flag is no longer possible,
because the gen_io_end() call has been deleted. We can therefore
safely remove the no-longer-valid assertion.

Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Message-id: 20210416170207.12504-1-alex.bennee@linaro.org
Cc: Cédric Le Goater <clg@kaod.org>
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2021-04-17 18:48:05 +01:00
Philippe Mathieu-Daudé 6b5fe13786 semihosting: Move include/hw/semihosting/ -> include/semihosting/
We want to move the semihosting code out of hw/ in the next patch.

This patch contains the mechanical steps, created using:

  $ git mv include/hw/semihosting/ include/
  $ sed -i s,hw/semihosting,semihosting, $(git grep -l hw/semihosting)

Signed-off-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Message-Id: <20210226131356.3964782-2-f4bug@amsat.org>
Message-Id: <20210305135451.15427-2-alex.bennee@linaro.org>
2021-03-10 15:34:12 +00:00
Rémi Denis-Courmont 926c1b9789 target/arm: Implement SCR_EL2.EEL2
This adds handling for the SCR_EL3.EEL2 bit.

Signed-off-by: Rémi Denis-Courmont <remi.denis.courmont@huawei.com>
Message-id: 20210112104511.36576-17-remi.denis.courmont@huawei.com
[PMM: Applied fixes for review issues noted by RTH:
 - check for FEATURE_AARCH64 before checking sel2 isar feature
 - correct the commit message subject line]
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2021-01-19 14:38:52 +00:00
Rémi Denis-Courmont 6b340aeb48 target/arm: revector to run-time pick target EL
On ARMv8-A, accesses by 32-bit secure EL1 to monitor registers trap to
the upper (64-bit) EL. With Secure EL2 support, we can no longer assume
that that is always EL3, so make room for the value to be computed at
run-time.

Signed-off-by: Rémi Denis-Courmont <remi.denis.courmont@huawei.com>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 20210112104511.36576-16-remi.denis.courmont@huawei.com
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2021-01-19 14:38:52 +00:00
Peter Maydell e4d51ac692 target/arm: Don't decode insns in the XScale/iWMMXt space as cp insns
In commit cd8be50e58 we converted the A32 coprocessor
insns to decodetree. This accidentally broke XScale/iWMMXt insns,
because it moved the handling of "cp insns which are handled
by looking up the cp register in the hashtable" from after the
call to the legacy disas_xscale_insn() decode to before it,
with the result that all XScale/iWMMXt insns now UNDEF.

Update valid_cp() so that it knows that on XScale cp 0 and 1
are not standard coprocessor instructions; this will cause
the decodetree trans_ functions to ignore them, so that
execution will correctly get through to the legacy decode again.

Cc: qemu-stable@nongnu.org
Reported-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Tested-by: Guenter Roeck <linux@roeck-us.net>
Message-id: 20210108195157.32067-1-peter.maydell@linaro.org
2021-01-12 21:19:02 +00:00
Peter Maydell f7ed0c9433 target/arm: Move general-use constant expanders up in translate.c
The constant-expander functions like negate, plus_2, etc, are
generally useful; move them up in translate.c so we can use them in
the VFP/Neon decoders as well as in the A32/T32/T16 decoders.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 20201119215617.29887-9-peter.maydell@linaro.org
2020-12-10 11:44:55 +00:00
Peter Maydell 6e21a013fb target/arm: Implement CLRM instruction
In v8.1M the new CLRM instruction allows zeroing an arbitrary set of
the general-purpose registers and APSR.  Implement this.

The encoding is a subset of the LDMIA T2 encoding, using what would
be Rn=0b1111 (which UNDEFs for LDMIA).

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 20201119215617.29887-6-peter.maydell@linaro.org
2020-12-10 11:44:55 +00:00
Peter Maydell 83ff3d6add target/arm: Implement VSCCLRM insn
Implement the v8.1M VSCCLRM insn, which zeros floating point
registers if there is an active floating point context.
This requires support in write_neon_element32() for the MO_32
element size, so add it.

Because we want to use arm_gen_condlabel(), we need to move
the definition of that function up in translate.c so it is
before the #include of translate-vfp.c.inc.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 20201119215617.29887-5-peter.maydell@linaro.org
2020-12-10 11:44:55 +00:00
Chetan Pant 50f57e09fd arm tcg cpus: Fix Lesser GPL version number
There is no "version 2" of the "Lesser" General Public License.
It is either "GPL version 2.0" or "Lesser GPL version 2.1".
This patch replaces all occurrences of "Lesser GPL version 2" with
"Lesser GPL version 2.1" in comment section.

Signed-off-by: Chetan Pant <chetan4windows@gmail.com>
Message-Id: <20201023122913.19561-1-chetan4windows@gmail.com>
Reviewed-by: Thomas Huth <thuth@redhat.com>
Signed-off-by: Thomas Huth <thuth@redhat.com>
2020-11-15 16:42:14 +01:00
Xinhao Zhang 7f350a87e3 target/arm: add space before the open parenthesis '('
Fix code style. Space required before the open parenthesis '('.

Signed-off-by: Xinhao Zhang <zhangxinhao1@huawei.com>
Signed-off-by: Kai Deng <dengkai1@huawei.com>
Message-id: 20201103114529.638233-3-zhangxinhao1@huawei.com
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2020-11-10 11:03:48 +00:00
Richard Henderson 8aab18a2c5 target/arm: Improve do_prewiden_3d
We can use proper widening loads to extend 32-bit inputs,
and skip the "widenfn" step.

Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 20201030022618.785675-12-richard.henderson@linaro.org
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2020-11-02 16:52:15 +00:00
Richard Henderson b38b96ca90 target/arm: Rename neon_load_reg64 to vfp_load_reg64
The only uses of this function are for loading VFP
double-precision values, and nothing to do with NEON.

Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 20201030022618.785675-10-richard.henderson@linaro.org
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2020-11-02 16:52:14 +00:00
Richard Henderson 0aa8e700a5 target/arm: Add read/write_neon_element64
Replace all uses of neon_load/store_reg64 within translate-neon.c.inc.

Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 20201030022618.785675-9-richard.henderson@linaro.org
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2020-11-02 16:52:14 +00:00
Richard Henderson 21c1c0e50b target/arm: Rename neon_load_reg32 to vfp_load_reg32
The only uses of this function are for loading VFP
single-precision values, and nothing to do with NEON.

Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 20201030022618.785675-8-richard.henderson@linaro.org
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2020-11-02 16:52:14 +00:00
Richard Henderson 4d5fa5a80a target/arm: Expand read/write_neon_element32 to all MemOp
We can then use this to improve VMOV (scalar to gp) and
VMOV (gp to scalar) so that we simply perform the memory
operation that we wanted, rather than inserting or
extracting from a 32-bit quantity.

These were the last uses of neon_load/store_reg, so remove them.

Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 20201030022618.785675-7-richard.henderson@linaro.org
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2020-11-02 16:52:14 +00:00
Richard Henderson a712266f5d target/arm: Add read/write_neon_element32
Model these off the aa64 read/write_vec_element functions.
Use it within translate-neon.c.inc.  The new functions do
not allocate or free temps, so this rearranges the calling
code a bit.

Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 20201030022618.785675-6-richard.henderson@linaro.org
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2020-11-02 16:52:13 +00:00
Richard Henderson d8719785fd target/arm: Use neon_element_offset in vfp_reg_offset
This seems a bit more readable than using offsetof CPU_DoubleU.

Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 20201030022618.785675-5-richard.henderson@linaro.org
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2020-11-02 16:52:13 +00:00
Richard Henderson 0f2cdc8227 target/arm: Use neon_element_offset in neon_load/store_reg
These are the only users of neon_reg_offset, so remove that.

Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 20201030022618.785675-4-richard.henderson@linaro.org
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2020-11-02 16:52:13 +00:00
Richard Henderson 7ec85c0283 target/arm: Move neon_element_offset to translate.c
This will shortly have users outside of translate-neon.c.inc.

Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 20201030022618.785675-3-richard.henderson@linaro.org
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2020-11-02 16:52:13 +00:00
Richard Henderson 015ee81a4c target/arm: Introduce neon_full_reg_offset
This function makes it clear that we're talking about the whole
register, and not the 32-bit piece at index 0.  This fixes a bug
when running on a big-endian host.

Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 20201030022618.785675-2-richard.henderson@linaro.org
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2020-11-02 16:52:12 +00:00
Peter Maydell b722636972 target/arm: Implement v8.1M low-overhead-loop instructions
v8.1M's "low-overhead-loop" extension has three instructions
for looping:
 * DLS (start of a do-loop)
 * WLS (start of a while-loop)
 * LE (end of a loop)

The loop-start instructions are both simple operations to start a
loop whose iteration count (if any) is in LR.  The loop-end
instruction handles "decrement iteration count and jump back to loop
start"; it also caches the information about the branch back to the
start of the loop to improve performance of the branch on subsequent
iterations.

As with the branch-future instructions, the architecture permits an
implementation to discard the LO_BRANCH_INFO cache at any time, and
QEMU takes the IMPDEF option to never set it in the first place
(equivalent to discarding it immediately), because for us a "real"
implementation would be unnecessary complexity.

(This implementation only provides the simple looping constructs; the
vector extension MVE (Helium) adds some extra variants to handle
looping across vectors.  We'll add those later when we implement
MVE.)

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 20201019151301.2046-8-peter.maydell@linaro.org
2020-10-20 16:12:01 +01:00
Peter Maydell 05903f036e target/arm: Implement v8.1M branch-future insns (as NOPs)
v8.1M implements a new 'branch future' feature, which is a
set of instructions that request the CPU to perform a branch
"in the future", when it reaches a particular execution address.
In hardware, the expected implementation is that the information
about the branch location and destination is cached and then
acted upon when execution reaches the specified address.
However the architecture permits an implementation to discard
this cached information at any point, and so guest code must
always include a normal branch insn at the branch point as
a fallback. In particular, an implementation is specifically
permitted to treat all BF insns as NOPs (which is equivalent
to discarding the cached information immediately).

For QEMU, implementing this caching of branch information
would be complicated and would not improve the speed of
execution at all, so we make the IMPDEF choice to implement
all BF insns as NOPs.

Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Message-id: 20201019151301.2046-7-peter.maydell@linaro.org
2020-10-20 16:12:01 +01:00
Peter Maydell 920f04fa3e target/arm: Don't allow BLX imm for M-profile
The BLX immediate insn in the Thumb encoding always performs
a switch from Thumb to Arm state. This would be totally useless
in M-profile which has no Arm decoder, and so the instruction
does not exist at all there. Make the encoding UNDEF for M-profile.

(This part of the encoding space is used for the branch-future
and low-overhead-loop insns in v8.1M.)

Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Message-id: 20201019151301.2046-6-peter.maydell@linaro.org
2020-10-20 16:12:01 +01:00
Peter Maydell cc73bbded0 target/arm: Implement v8.1M conditional-select insns
v8.1M brings four new insns to M-profile:
 * CSEL  : Rd = cond ? Rn : Rm
 * CSINC : Rd = cond ? Rn : Rm+1
 * CSINV : Rd = cond ? Rn : ~Rm
 * CSNEG : Rd = cond ? Rn : -Rm

Implement these.

Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Message-id: 20201019151301.2046-4-peter.maydell@linaro.org
2020-10-20 16:12:01 +01:00
Peter Maydell 5288145d71 target/arm: Fix SMLAD incorrect setting of Q bit
The SMLAD instruction is supposed to:
 * signed multiply Rn[15:0] * Rm[15:0]
 * signed multiply Rn[31:16] * Rm[31:16]
 * perform a signed addition of the products and Ra
 * set Rd to the low 32 bits of the theoretical
   infinite-precision result
 * set the Q flag if the sign-extension of Rd
   would differ from the infinite-precision result
   (ie on overflow)

Our current implementation doesn't quite do this, though: it performs
an addition of the products setting Q on overflow, and then it adds
Ra, again possibly setting Q.  This sometimes incorrectly sets Q when
the architecturally mandated only-check-for-overflow-once algorithm
does not. For instance:
 r1 = 0x80008000; r2 = 0x80008000; r3 = 0xffffffff
 smlad r0, r1, r2, r3
This is (-32768 * -32768) + (-32768 * -32768) - 1

The products are both 0x4000_0000, so when added together as 32-bit
signed numbers they overflow (and QEMU sets Q), but because the
addition of Ra == -1 brings the total back down to 0x7fff_ffff
there is no overflow for the complete operation and setting Q is
incorrect.

Fix this edge case by resorting to 64-bit arithmetic for the
case where we need to add three values together.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 20201009144712.11187-1-peter.maydell@linaro.org
2020-10-20 16:12:00 +01:00
Peter Maydell a84d1d1316 target/arm: Make A32/T32 use new fpstatus_ptr() API
Make A32/T32 code use the new fpstatus_ptr() API:
 get_fpstatus_ptr(0) -> fpstatus_ptr(FPST_FPCR)
 get_fpstatus_ptr(1) -> fpstatus_ptr(FPST_STD)

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Message-id: 20200806104453.30393-3-peter.maydell@linaro.org
2020-08-24 10:15:11 +01:00
Peter Maydell 8b4c9a50dc target/arm/translate.c: Delete/amend incorrect comments
In arm_tr_init_disas_context() we have a FIXME comment that suggests
"cpu_M0 can probably be the same as cpu_V0".  This isn't in fact
possible: cpu_V0 is used as a temporary inside gen_iwmmxt_shift(),
and that function is called in various places where cpu_M0 contains a
live value (i.e.  between gen_op_iwmmxt_movq_M0_wRn() and
gen_op_iwmmxt_movq_wRn_M0() calls).  Remove the comment.

We also have a comment on the declarations of cpu_V0/V1/M0 which
claims they're "for efficiency".  This isn't true with modern TCG, so
replace this comment with one which notes that they're only used with
the iwmmxt decode.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 20200803132815.3861-1-peter.maydell@linaro.org
2020-08-24 10:15:11 +01:00
Peter Maydell e60527c5d5 target/arm: Delete unused VFP_DREG macros
As part of the Neon decodetree conversion we removed all
the uses of the VFP_DREG macros, but forgot to remove the
macro definitions. Do so now.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Message-id: 20200803124848.18295-1-peter.maydell@linaro.org
2020-08-24 10:15:11 +01:00