Certain branch instructions specify that the result of (simm16 * 4)
gets sign-extended before being added to the PC.
Previously, that result was being sign extended as if it was still a
16-bit number. This patch fixes that by having the result be sign
extended as an 18-bit number.
Change-Id: Id4d430f8daa71ca7910b570e7e39790626f1decf
Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/41053
Reviewed-by: Matt Sinclair <mattdsinclair@gmail.com>
Reviewed-by: Matthew Poremba <matthew.poremba@amd.com>
Maintainer: Matt Sinclair <mattdsinclair@gmail.com>
Tested-by: kokoro <noreply+kokoro@google.com>
The idea of this template was to distinguish types which should
grow/shrink based on the native size of the ABI in question. Or in other
words, if the ABI was 32 bit, the type should also be 32 bit, or 64 bit
and 64 bit.
Unfortunately, I had intended for Addr to be a conforming type (since
local pointers would be conforming), but uint64_t not to be. Since Addr
is defined as a typedef of uint64_t, the compiler would make *both*
types conforming, giving incorrect behavior on 32 bit systems.
Local pointers will need to be handled in a different way, likely with
the VPtr template, so that they will be treated correctly and not like
an explicitly 64 bit data type.
Change-Id: Idfdd5351260b48bb531a1926b93e0478a297826d
Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/40495
Reviewed-by: Gabe Black <gabe.black@gmail.com>
Maintainer: Gabe Black <gabe.black@gmail.com>
Tested-by: kokoro <noreply+kokoro@google.com>
This type is primarily used to determine the size of a pointer when
using that ABI, similar to the uintptr_t type, but also less directly
to determine the "native" size of the ABI. For instance, for 32 bit ARM
ABIs, it should be defined as uint32_t since that's both the size of a
uintptr_t, and, less directly, the size of a 32 bit ARM register and
"naturally" sized types in that ABI.
This type can be used by the VPtr template to retrieve its actual value
from a simcall's parameters. In general, when accepting or returning a
pointer or address in a simcall, the VPtr template should be used so
that it's managed correctly by GuestABI. Addr will be treated as a
uint64_t allways which will be incorrect for 32 bit ABIs.
Change-Id: I3af046917387541d6faff96a21a1f1dbf7317e06
Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/40496
Maintainer: Gabe Black <gabe.black@gmail.com>
Tested-by: kokoro <noreply+kokoro@google.com>
Reviewed-by: Bobby R. Bruce <bbruce@ucdavis.edu>
This DPRINTF accesses the ExtMachInst typed machInst member of the
StaticInst class, and so is ISA dependent. Move the DPRINTF to where the
instructions are actually decoded where that type doesn't have to be
disambiguated.
Also, this change makes this DPRINTF more accurate, since microops are
not really "decoded" when they are extracted from a macroop. The process
of unpacking them to feed into the rest of the CPU should be fairly
trivial, so really they're just being retrieved. With the DPRINTF in
this new position, it will only trigger when an instruction is actually
decoded from memory.
Change-Id: I14145165b93bb004057a729fa7909cd2d3d34d29
Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/40099
Reviewed-by: Jason Lowe-Power <power.jg@gmail.com>
Maintainer: Jason Lowe-Power <power.jg@gmail.com>
Tested-by: kokoro <noreply+kokoro@google.com>
Per the AMD64 Architecture Programming Manual:
The size of the count register (CX, ECX, or RCX) depends on the
address-size attribute of the JrCXZ instruction. Therefore, JRCXZ can
only be executed in 64-bit mode
and
In 64-bit mode, the operand size defaults to 64 bits. The processor
sign-extends the 8-bit displacement value to 64 bits before adding it
to the RIP.
This patch also renames the instruction from JRCX to JRCXZ to match the
language in the programming manual.
Change-Id: Id55147d0602ff41ad6aaef483bef722ff56cae62
Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/40195
Reviewed-by: Matt Sinclair <mattdsinclair@gmail.com>
Maintainer: Matt Sinclair <mattdsinclair@gmail.com>
Tested-by: kokoro <noreply+kokoro@google.com>
This takes the place of direct access to the machInst field as used in
the MinorCPU model which makes the incorrect assumption that it can
arbitrarily treat the ExtMachInst as an integer, and that masking in a
certain way can meaningfully classify what the instruction will do.
Because that assumption is not correct in general, that had been
ifdef-ed out in most ISAs except ARM, and for the other ISAs the value
was simply set to zero.
Change-Id: I8ac05e65475edc3ccc044afdff09490e2c05ba07
Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/40098
Reviewed-by: Giacomo Travaglini <giacomo.travaglini@arm.com>
Maintainer: Giacomo Travaglini <giacomo.travaglini@arm.com>
Maintainer: Bobby R. Bruce <bbruce@ucdavis.edu>
Tested-by: kokoro <noreply+kokoro@google.com>
This should help reduce warning spew when building with newer compilers.
The pybind11::module type has been renamed pybind11::module_ to avoid
conflicts with c++20 modules, according to the pybind11 changelog, so
this CL also updates gem5 source to use the new type. There is
supposedly an alias pybind11::module which is for compatibility, but we
still get linker errors without changing to pybind11::module_.
Change-Id: I0acb36215b33e3a713866baec43f5af630c356ee
Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/40255
Maintainer: Bobby R. Bruce <bbruce@ucdavis.edu>
Reviewed-by: Bobby R. Bruce <bbruce@ucdavis.edu>
Tested-by: kokoro <noreply+kokoro@google.com>
Previously we use attribute and event for communication between gem5
SimObject to systemC fastmodel sc_module. Creating a base class allows us
to perform casting once and get all the interface required. Also,
instead of warning on attribute not found, we should make simulator
panic if the sc_module does not provide the interface we need.
Change-Id: I91e1036cb792d556dfc4010e7a0f138b1519b079
Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/40277
Reviewed-by: Gabe Black <gabe.black@gmail.com>
Maintainer: Gabe Black <gabe.black@gmail.com>
Tested-by: kokoro <noreply+kokoro@google.com>
The register cntfrq should be set to system counter frequency.
However, the current fastmodel implementation accidentally set it to
core frequency. This CL removes the wrong implementation, and real
cntfrq setting is performed in the initState.
Change-Id: I6c62822a4fbbcc0c499f79f6003dabb0c133f997
Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/40276
Reviewed-by: Gabe Black <gabe.black@gmail.com>
Maintainer: Gabe Black <gabe.black@gmail.com>
Tested-by: kokoro <noreply+kokoro@google.com>
Some CSR register is physically shared between different privilige
level. Current implementation of CSR setting only considers to verify
the bits visable in current privilige level, and directly writes the
masked bits back to register. This leads to other bits invisable
to current mode is overwritten and wrong behavior across the modes.
Thus, CSR updating should always keep the bits value for other modes.
e.g. disabling interrupt in S mode with setting
SSTATUS SIE bit will lead to clear MIE bit as well (the interrupt
is disabled unintentionally).
All CSR register sharing same physical register in different mode
may have similar issue. I only fixed some important ones.
The fix is verified in FS.
Jira Issue: https://gem5.atlassian.net/browse/GEM5-860
Change-Id: I34d4766a4b483b5add2c3bbefd28b21b9abf37f6
Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/39036
Tested-by: kokoro <noreply+kokoro@google.com>
Reviewed-by: Ayaz Akram <yazakram@ucdavis.edu>
Maintainer: Jason Lowe-Power <power.jg@gmail.com>
The base/refcnt.hh header was not used in base/types.hh at all, and
enum/ByteOrder.hh was there just so other files could find it. Instead,
this change moves enum/Byteorder.hh to sim/byteswap.hh where it's fits
with the purpose of the header.
This change also fixes some style problems with the code in
base/types.hh itself.
Change-Id: I471ae5cb2cca9169ba8616fb8411b40108a3ffb2
Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/39855
Reviewed-by: Daniel Carvalho <odanrc@yahoo.com.br>
Maintainer: Gabe Black <gabe.black@gmail.com>
Tested-by: kokoro <noreply+kokoro@google.com>
This ABI is effectively used by both the gem5 ops and system calls, in
system calls because it only relies on registers, and in gem5 ops by
inheritance.
Even though these ABIs happen to be the same and were initially defined
to be the same, this change creates a root "reg" ABI which will act as a
root for both so that there isn't an implication that changes to one
should be changes to both.
Change-Id: I8726d8628503be2ad7616a71cc48b66f13e7d955
Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/39318
Reviewed-by: Jason Lowe-Power <power.jg@gmail.com>
Reviewed-by: Ayaz Akram <yazakram@ucdavis.edu>
Maintainer: Gabe Black <gabe.black@gmail.com>
Tested-by: kokoro <noreply+kokoro@google.com>
We currently use the traditional SI-like prefixes to represent
binary multipliers in some contexts. This is ambiguous in many cases
since they overload the meaning of the SI prefix.
Here are some examples of commonly used in the industry:
* Storage vendors define 1 MB as 10**6 bytes
* Memory vendors define 1 MB as 2**20 bytes
* Network equipment treats 1Mbit/s as 10**6 bits/s
* Memory vendors define 1Mbit as 2**20 bits
In practice, this means that a FLASH chip on a storage bus uses
decimal prefixes, but that same flash chip on a memory bus uses binary
prefixes. It would also be reasonable to assume that the contents of a
1Mbit FLASH chip would take 0.1s to transfer over a 10Mbit Ethernet
link. That's however not the case due to different meanings of the
prefix.
The quantity 2MX is treated differently by gem5 depending on the unit
X:
* Physical quantities (s, Hz, V, A, J, K, C, F) use decimal prefixes.
* Interconnect and NoC bandwidths (B/s) use binary prefixes.
* Network bandwidths (bps) use decimal prefixes.
* Memory sizes and storage sizes (B) use binary prefixes.
Mitigate this ambiguity by consistently using the ISO/IEC/SI prefixes
for binary multipliers for parameters and comments where appropriate.
Change-Id: I9b47194d26d71c8ebedda6c31a5bac54b600d3bf
Signed-off-by: Andreas Sandberg <andreas.sandberg@arm.com>
Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/39575
Reviewed-by: Richard Cooper <richard.cooper@arm.com>
Tested-by: kokoro <noreply+kokoro@google.com>
Those instructions were broken after:
https://gem5-review.googlesource.com/c/public/gem5/+/38381/4
Which is effectively replacing the generic StaticInst src and dest
reg array with an instruction specific one.
The size of the array is evaluated by the ISA parser, which is
counting the operands when parsing the isa code.
Alas, Compare and Swap Pair instructions were augmenting the number
of destination and source registers in the C++ world, which is
invisible to the parser. This lead to an out of bounds access
of the arrays.
This patch is fixing this behaviour by defining XResult2, which
is the second compare/result register for a paired CAS
Change-Id: Ie35c26256f42459805e007847896ac58b178fd42
Signed-off-by: Giacomo Travaglini <giacomo.travaglini@arm.com>
Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/39456
Reviewed-by: Richard Cooper <richard.cooper@arm.com>
Reviewed-by: Gabe Black <gabe.black@gmail.com>
Tested-by: kokoro <noreply+kokoro@google.com>
