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path: root/src/arch/x86/isa/insts/x87
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2017-12-06x86: Split apart x87's FSW and TOP, and add a missing break.Gabe Black
The FSW and TOP values are technically part of the same register, but they have very different behaviors. One of them can be renamed and float along without affecting global state, while the other requires serialization. They just need to *look* like the same register when read by the user. Also, there was a missing break in setMiscRegNoEffect. Change-Id: If58de0f566f65068208240f4001209fb9e1826d6 Reviewed-on: https://gem5-review.googlesource.com/6441 Reviewed-by: Jason Lowe-Power <jason@lowepower.com> Maintainer: Gabe Black <gabeblack@google.com>
2015-10-06x86: implement fild, fucomi, and fucomip x87 instsSteve Reinhardt
fild loads an integer value into the x87 top of stack register. fucomi/fucomip compare two x87 register values (the latter also doing a stack pop). These instructions are used by some versions of GNU libstdc++.
2015-07-04x86: Adjust the size of the values written to the x87 misc registersNikos Nikoleris
All x87 misc registers are implemented in an array of 64 bit values but in real hardware the size of some of these registers is smaller. Previsouly all 64 bits where incorrectly set and then later read. To ensure correctness we mask the value in setMiscRegNoEffect to write only the valid bits. Committed by: Nilay Vaish <nilay@cs.wisc.edu>
2015-04-13x86: implements x87 mult/div instructionsNilay Vaish
2014-10-16arch: Use shared_ptr for all FaultsAndreas Hansson
This patch takes quite a large step in transitioning from the ad-hoc RefCountingPtr to the c++11 shared_ptr by adopting its use for all Faults. There are no changes in behaviour, and the code modifications are mostly just replacing "new" with "make_shared".
2014-01-27x86: use lfpimm instead of limm for fptanNilay Vaish
2014-01-27x86: implements x87 add/sub instructionsNilay Vaish
2014-01-27x86: implements fxch instruction.Nilay Vaish
2013-09-30x86: Add support for FLDENV & FNSTENVAndreas Sandberg
2013-09-30x86: Add support for loading 32-bit and 80-bit floats in the x87Andreas Sandberg
The x87 FPU supports three floating point formats: 32-bit, 64-bit, and 80-bit floats. The current gem5 implementation supports 32-bit and 64-bit floats, but only works correctly for 64-bit floats. This changeset fixes the 32-bit float handling by correctly loading and rounding (using truncation) 32-bit floats instead of simply truncating the bit pattern. 80-bit floats are loaded by first loading the 80-bits of the float to two temporary integer registers. A micro-op (cvtint_fp80) then converts the contents of the two integer registers to the internal FP representation (double). Similarly, when storing an 80-bit float, there are two conversion routines (ctvfp80h_int and cvtfp80l_int) that convert an internal FP register to 80-bit and stores the upper 64-bits or lower 32-bits to an integer register, which is the written to memory using normal integer stores.
2013-09-30x86: Fix re-entrancy problems in x87 store instructionsAndreas Sandberg
X87 store instructions typically loads and pops the top value of the stack and stores it in memory. The current implementation pops the stack at the same time as the floating point value is loaded to a temporary register. This will corrupt the state of the x87 stack if the store fails. This changeset introduces a pop87 micro-instruction that pops the stack and uses this instruction in the affected macro-instructions to pop the stack after storing the value to memory.
2013-06-18x86: Fix loading of floating point constantsAndreas Sandberg
This changeset actually fixes two issues: * The lfpimm instruction didn't work correctly when applied to a floating point constant (it did work for integers containing the bit string representation of a constant) since it used reinterpret_cast to convert a double to a uint64_t. This caused a compilation error, at least, in gcc 4.6.3. * The instructions loading floating point constants in the x87 processor didn't work correctly since they just stored a truncated integer instead of a double in the floating point register. This changeset fixes the old microcode by using lfpimm instruction instead of the limm instructions.
2013-06-18x86: Make fprem like the fprem on a real x87Andreas Sandberg
The current implementation of fprem simply does an fmod and doesn't simulate any of the iterative behavior in a real fprem. This isn't normally a problem, however, it can lead to problems when switching between CPU models. If switching from a real CPU in the middle of an fprem loop to a simulated CPU, the output of the fprem loop becomes correupted. This changeset changes the fprem implementation to work like the one on real hardware.
2013-06-18x86: Fix the flag handling code in FABS and FCHSAndreas Sandberg
This changeset fixes two problems in the FABS and FCHS implementation. First, the ISA parser expects the assignment in flag_code to be a pure assignment and not an and-assignment, which leads to the isa_parser omitting the misc reg update. Second, the FCHS and FABS macro-ops don't set the SetStatus flag, which means that the default micro-op version, which doesn't update FSW, is executed.
2013-03-11x86: implement some of the x87 instructionsNilay Vaish
This patch implements ftan, fprem, fyl2x, fld* floating-point instructions.
2013-01-15x86: implements fsin, fcos instructionsNilay Vaish
2013-01-15x86: implement fabs, fchs instructionsNilay Vaish
2012-12-30x86: implement x87 fp instruction fnstswNilay Vaish
This patch implements the fnstsw instruction. The code was originally written by Vince Weaver. Gabe had made some comments about the code, but those were never addressed. This patch addresses those comments.
2012-12-30x86: implement x87 fp instruction fsincosNilay Vaish
This patch implements the fsincos instruction. The code was originally written by Vince Weaver. Gabe had made some comments about the code, but those were never addressed. This patch addresses those comments.
2010-05-23copyright: Change HP copyright on x86 code to be more friendlyNathan Binkert
2009-08-20X86: Fix the decoding for and fill out FST and FSTP.Gabe Black
2007-10-02X86: Fix x87 floating point stack register indexing.Gabe Black
--HG-- extra : convert_revision : b515ec20cbfc50b38aa7da6cf4d465acf9054c08
2007-10-02X86: Fix up the microcode for the FST and FSTP instructions.Gabe Black
--HG-- extra : convert_revision : ad68633e9b7eab425593acb20cf242bf98c2b642
2007-09-19X86: Implement the fld, fst, and fstp instructions.Gabe Black
--HG-- extra : convert_revision : 7dd274bdc3c34839c17d9012a745d7c95dfcfdd8
2007-09-19X86: Put in stubs for x87, 64 bit and 128 bit SIMD instruction microcode.Gabe Black
--HG-- rename : src/arch/x86/isa/insts/sse/__init__.py => src/arch/x86/isa/insts/simd128/__init__.py extra : convert_revision : efb4405aebaa4a04f33572e7d078ceca45872d9c