The FPSCR[FI] bit indicates if the last floating point instruction had a result that was rounded. Each consecutive floating point instruction is suppose to set this bit to the correct value. What currently happens is this bit is not set as often as it should be. I have verified that this is the behavior of a real PowerPC 950. This patch fixes that problem by deciding to set this bit after each floating point instruction.
https://www.pdfdrive.net/powerpc-microprocessor-family-the-programming-environments-for-32-e3087633.html
Page 63 in table 2-4 is where the description of this bit can be found.
Signed-off-by: John Arbuckle <programmingkidx@gmail.com>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Fix the helper_fpscr_clrbit() function so it correctly sets the FEX
and VX bits.
Determining the value for the Floating Point Status and Control
Register's (FPSCR) FEX bit is suppose to be done like this:
FEX = (VX & VE) | (OX & OE) | (UX & UE) | (ZX & ZE) | (XX & XE))
It is described as "the logical OR of all the floating-point exception
bits masked by their respective enable bits". It was not implemented
correctly. The value of FEX would stay on even when all other bits
were set to off.
The VX bit is described as "the logical OR of all of the invalid
operation exceptions". This bit was also not implemented correctly. It
too would stay on when all the other bits were set to off.
My main source of information is an IBM document called:
PowerPC Microprocessor Family:
The Programming Environments for 32-Bit Microprocessors
Page 62 is where the FPSCR information is located.
This is an older copy than the one I use but it is still very useful:
https://www.pdfdrive.net/powerpc-microprocessor-family-the-programming-environments-for-32-e3087633.html
I use a G3 and G5 iMac to compare bit values with QEMU. This patch
fixed all the problems I was having with these bits.
Signed-off-by: John Arbuckle <programmingkidx@gmail.com>
[dwg: Re-wrapped commit message]
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Only MIPS requires snan_bit_is_one to be variable. While we are
specializing softfloat behaviour, allow other targets to eliminate
this runtime check.
Cc: Aurelien Jarno <aurelien@aurel32.net>
Cc: Yongbok Kim <yongbok.kim@mips.com>
Cc: David Gibson <david@gibson.dropbear.id.au>
Cc: Alexander Graf <agraf@suse.de>
Cc: Guan Xuetao <gxt@mprc.pku.edu.cn>
Tested-by: Alex Bennée <alex.bennee@linaro.org>
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
As cpu.h is another typically widely included file which doesn't need
full access to the softfloat API we can remove the includes from here
as well. Where they do need types it's typically for float_status and
the rounding modes so we move that to softfloat-types.h as well.
As a result of not having softfloat in every cpu.h call we now need to
add it to various helpers that do need the full softfloat.h
definitions.
Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
[For PPC parts]
Acked-by: David Gibson <david@gibson.dropbear.id.au>
Use the helper routine float[32,64]_maddsub_update_excp() in VSX_MADD
macro.
Signed-off-by: Nikunj A Dadhania <nikunj@linux.vnet.ibm.com>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Adds FPU_MADDSUB_UPDATE macro, this will be used for other routines
having float32/16
Signed-off-by: Nikunj A Dadhania <nikunj@linux.vnet.ibm.com>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Current order of checking does not confirm with the spec
(ISA 3.0: MultiplyAddDP page-469). Change the order and make them
independent of each other.
For example: a = infinity, b = zero, c = SNaN, this should set both
VXIMZ and VXNAN
Signed-off-by: Nikunj A Dadhania <nikunj@linux.vnet.ibm.com>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Use the softfloat api for fused multiply-add.
Introduce routine to set the FPSCR flags VXNAN, VXIMZ nad VMISI.
Signed-off-by: Nikunj A Dadhania <nikunj@linux.vnet.ibm.com>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
xscvqpudz: VSX Scalar truncate & Convert Quad-Precision format to
Unsigned Doubleword format
xscvqpuwz: VSX Scalar truncate & Convert Quad-Precision format to
Unsigned Word format
Signed-off-by: Bharata B Rao <bharata@linux.vnet.ibm.com>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
xsaddqpo: VSX Scalar Add Quad-Precision using round to Odd
xsmulqo: VSX Scalar Multiply Quad-Precision using round to Odd
xsdivqpo: VSX Scalar Divide Quad-Precision using round to Odd
xscvqpdpo: VSX Scalar round & Convert Quad-Precision format to
Double-Precision format using round to Odd
xssqrtqpo: VSX Scalar Square Root Quad-Precision using round to Odd
xssubqpo: VSX Scalar Subtract Quad-Precision using round to Odd
In addition, fix the invalid bitmask in the instruction encoding
of xssqrtqp[o].
Signed-off-by: Bharata B Rao <bharata@linux.vnet.ibm.com>
CC: Jose Ricardo Ziviani <joserz@linux.vnet.ibm.com>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
xststdcsp: VSX Scalar Test Data Class Single-Precision
xststdcdp: VSX Scalar Test Data Class Double-Precision
xststdcqp: VSX Scalar Test Data Class Quad-Precision
Signed-off-by: Nikunj A Dadhania <nikunj@linux.vnet.ibm.com>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
xvtstdcsp: VSX Vector Test Data Class Single-Precision
xvtstdcdp: VSX Vector Test Data Class Double-Precision
Signed-off-by: Nikunj A Dadhania <nikunj@linux.vnet.ibm.com>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
xvcvhpsp: VSX Vector Convert Half Precision to Single Precision
xvcvsphp: VSX Vector Convert Single Precision to Half Precision
Signed-off-by: Nikunj A Dadhania <nikunj@linux.vnet.ibm.com>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
xscvsdqp: VSX Scalar Convert Signed Doubleword format to
Quad-Precision format
xscvudqp: VSX Scalar Convert Unsigned Doubleword format to
Quad-Precision format
Signed-off-by: Bharata B Rao <bharata@linux.vnet.ibm.com>
Signed-off-by: Nikunj A Dadhania <nikunj@linux.vnet.ibm.com>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
xscmpoqp, xscmpuqp & xscmpexpqp were added before f128 field was
introduced in ppc_vsr_t. Now that we have it, use it instead of
generating the 128 bit float using two 64bit fields.
Signed-off-by: Bharata B Rao <bharata@linux.vnet.ibm.com>
Signed-off-by: Nikunj A Dadhania <nikunj@linux.vnet.ibm.com>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
xscvqpsdz: VSX Scalar truncate & Convert Quad-Precision format to
Signed Doubleword format
xscvqpswz: VSX Scalar truncate & Convert Quad-Precision format to
Signed Word format
Signed-off-by: Bharata B Rao <bharata@linux.vnet.ibm.com>
Signed-off-by: Nikunj A Dadhania <nikunj@linux.vnet.ibm.com>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
xscvqpdp: VSX Scalar round & Convert Quad-Precision format to
Double-Precision format
Signed-off-by: Bharata B Rao <bharata@linux.vnet.ibm.com>
Signed-off-by: Nikunj A Dadhania <nikunj@linux.vnet.ibm.com>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
xscvdpqp: VSX Scalar Convert Double-Precision format to
Quad-Precision format
Signed-off-by: Bharata B Rao <bharata@linux.vnet.ibm.com>
Signed-off-by: Nikunj A Dadhania <nikunj@linux.vnet.ibm.com>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Use correct FP precision when setting FPRF in FP conversion helpers
instead of always assuming float64 precision.
Signed-off-by: Bharata B Rao <bharata@linux.vnet.ibm.com>
Signed-off-by: Nikunj A Dadhania <nikunj@linux.vnet.ibm.com>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
xscvdphp: VSX Scalar round & Convert Double-Precision format to
Half-Precision format
xscvhpdp: VSX Scalar Convert Half-Precision format to
Double-Precision format
Signed-off-by: Bharata B Rao <bharata@linux.vnet.ibm.com>
Signed-off-by: Nikunj A Dadhania <nikunj@linux.vnet.ibm.com>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Since helper_compute_fprf() works on float64 argument, rename it
to helper_compute_fprf_float64(). Also use a macro to generate
helper_compute_fprf_float64() so that float128 version of the same
helper can be introduced easily later.
Signed-off-by: Bharata B Rao <bharata@linux.vnet.ibm.com>
Signed-off-by: Nikunj A Dadhania <nikunj@linux.vnet.ibm.com>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Replace isden() by float64_is_zero_or_denormal() so that code in
helper_compute_fprf() can be reused to work with float128 argument.
Signed-off-by: Bharata B Rao <bharata@linux.vnet.ibm.com>
Signed-off-by: Nikunj A Dadhania <nikunj@linux.vnet.ibm.com>
Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Use float64 argument instead of unit64_t in helper_compute_fprf()
This allows code in helper_compute_fprf() to be reused later to
work with float128 argument too.
Signed-off-by: Bharata B Rao <bharata@linux.vnet.ibm.com>
Signed-off-by: Nikunj A Dadhania <nikunj@linux.vnet.ibm.com>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
The structure and corresponding defines and functions need to be used
outside of fpu_helper.c as well.
Add u8, u16, u32 and Int128 to the structure.
Signed-off-by: Nikunj A Dadhania <nikunj@linux.vnet.ibm.com>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
- xscmpodp & xscmpudp are missing flags reset.
- In xscmpodp, VXCC should be set only if VE is 0 for signalling NaN case
and VXCC should be set by explicitly checking for quiet NaN case.
- Comparison is being done only if the operands are not NaNs. However as
per ISA, it should be done even when operands are NaNs.
Signed-off-by: Bharata B Rao <bharata@linux.vnet.ibm.com>
Signed-off-by: Nikunj A Dadhania <nikunj@linux.vnet.ibm.com>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Move instruction decode helpers to target-ppc/internal.h so that some
of these can be used from outside of translate.c. This movement also
helps to get rid of some duplicate helpers from target-ppc/fpu_helper.c.
Suggested-by: Nikunj A Dadhania <nikunj@linux.vnet.ibm.com>
Signed-off-by: Bharata B Rao <bharata@linux.vnet.ibm.com>
Signed-off-by: Nikunj A Dadhania <nikunj@linux.vnet.ibm.com>
Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
We've currently got 18 architectures in QEMU, and thus 18 target-xxx
folders in the root folder of the QEMU source tree. More architectures
(e.g. RISC-V, AVR) are likely to be included soon, too, so the main
folder of the QEMU sources slowly gets quite overcrowded with the
target-xxx folders.
To disburden the main folder a little bit, let's move the target-xxx
folders into a dedicated target/ folder, so that target-xxx/ simply
becomes target/xxx/ instead.
Acked-by: Laurent Vivier <laurent@vivier.eu> [m68k part]
Acked-by: Bastian Koppelmann <kbastian@mail.uni-paderborn.de> [tricore part]
Acked-by: Michael Walle <michael@walle.cc> [lm32 part]
Acked-by: Cornelia Huck <cornelia.huck@de.ibm.com> [s390x part]
Reviewed-by: Christian Borntraeger <borntraeger@de.ibm.com> [s390x part]
Acked-by: Eduardo Habkost <ehabkost@redhat.com> [i386 part]
Acked-by: Artyom Tarasenko <atar4qemu@gmail.com> [sparc part]
Acked-by: Richard Henderson <rth@twiddle.net> [alpha part]
Acked-by: Max Filippov <jcmvbkbc@gmail.com> [xtensa part]
Reviewed-by: David Gibson <david@gibson.dropbear.id.au> [ppc part]
Acked-by: Edgar E. Iglesias <edgar.iglesias@xilinx.com> [crisµblaze part]
Acked-by: Guan Xuetao <gxt@mprc.pku.edu.cn> [unicore32 part]
Signed-off-by: Thomas Huth <thuth@redhat.com>
