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--HG--
extra : convert_revision : d64fe734fcdcc414ba9af9fc5f0f795429d5dad3
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doesn't compile.
src/arch/x86/isa/decoder/one_byte_opcodes.isa:
src/arch/x86/isa/macroop.isa:
src/arch/x86/isa/main.isa:
src/arch/x86/isa/microasm.isa:
src/arch/x86/isa/microops/base.isa:
src/arch/x86/isa/microops/microops.isa:
src/arch/x86/isa/operands.isa:
src/arch/x86/isa/microops/regop.isa:
src/arch/x86/isa/microops/specop.isa:
Reworking x86's microcode system
--HG--
extra : convert_revision : cab66be59ed758b192226af17eddd5a86aa190f3
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src/arch/x86/isa/decoder/one_byte_opcodes.isa:
Give the "MOV" instruction the format of it's arguments. This will likely need to be completely overhauled in the near future.
src/arch/x86/predecoder.cc:
src/arch/x86/predecoder.hh:
Make the predecoder explicitly reset itself rather than counting on it happening naturally.
src/arch/x86/predecoder_tables.cc:
Fix the immediate size table
src/arch/x86/regfile.cc:
nextnpc is bogus
--HG--
extra : convert_revision : 0926701fedaab41817e64bb05410a25174484a5a
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test the stub code for instructions.
--HG--
extra : convert_revision : a377daf20545dfcbb0f97d8cafbe3d68416dc4b2
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returned by the decoder has been fleshed out more. The following steps describe how an instruction implementation becomes a StaticInst.
1. Microops are created. These are StaticInsts use templates to provide a basic form of polymorphism without having to make the microassembler smarter.
2. An instruction class is created which has a "templated" microcode program as it's docstring. The template parameters are refernced with ^ following by a number.
3. An instruction in the decoder references an instruction template using it's mnemonic. The parameters to it's format end up replacing the placeholders. These parameters describe a source for an operand which could be memory, a register, or an immediate. It it's a register, the register index is used. If it's memory, eventually a load/store will be pre/postpended to the instruction template and it's destination register will be used in place of the ^. If it's an immediate, the immediate is used. Some operand types, specifically those that come from the ModRM byte, need to be decoded further into memory vs. register versions. This is accomplished by making the decode_block text for these instructions another case statement based off ModRM.
4. Once all of the template parameters have been handled, the instruction goes throw the microcode assembler which resolves labels and creates a list of python op objects. If an operand is a register, it uses a % prefix, an immediate uses $, and a label uses @. If the operand is just letters, numbers, and underscores, it can appear immediately after the prefix. If it's not, it can be encolsed in non nested {}s.
5. If there is a single "op" object (which corresponds to a single microop) the decoder is set up to return it directly. If not, a macroop wrapper is created around it.
In the future, I'm considering seperating the operand type specialization from the template substitution step. A problem this introduces is that either the template arguments need to be kept around for the specialization step, or they need to be re-extracted. Re-extraction might be the way to go so that the operand formats can be coded directly into the micro assembler template without having to pass them in as parameters. I don't know if that's actually useful, though.
src/arch/x86/isa/decoder/one_byte_opcodes.isa:
src/arch/x86/isa/microasm.isa:
src/arch/x86/isa/microops/microops.isa:
src/arch/x86/isa/operands.isa:
src/arch/x86/isa/microops/base.isa:
Implemented polymorphic microops and changed around the microcode assembler syntax.
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extra : convert_revision : e341f7b8ea9350a31e586a3d33250137e5954f43
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definitions to make figuring out what's what a little easier:
MicroOp: A single operation actually implemented in hardware.
MacroOp: A collection of microops which are executed as a unit.
Instruction: An architected instruction which can be implemented with a macroop or a microop.
--HG--
extra : convert_revision : 1cfc8409cc686c75220767839f55a30551aa6f13
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multiops do alot more of what they're supposed to (excluding memory operands), and microops are slightly more implemented.
--HG--
extra : convert_revision : 518059f47e11df50aa450d4a322ef2ac069c99c9
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instructions to return an instance of the right class. The code to decode register numbers and generate loads and stores still needs to be added. Also, a syntax for specifying operands as sources, destinations, or both needs to be established. Multipl microop instructions are also not handled, pending real macroop generation support.
--HG--
extra : convert_revision : 1a0a4b36afce8255e23e3cdd7a85c1392dda5f72
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actually work.
--HG--
extra : convert_revision : f62a1f035cc11677df8eb5a839ca1247d819fab3
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different sets of inputs.
--HG--
extra : convert_revision : 6a5be61831588f801965dd4e80cb52f28911c320
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what bits decode is done on to reflect where clumps of instructions are.
--HG--
extra : convert_revision : 8768676eac25e6a4f0dc50ce2dc576bdcdd6e025
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--HG--
rename : src/arch/x86/isa/decoder.isa => src/arch/x86/isa/decoder/decoder.isa
extra : convert_revision : a60e7495da6fe99fa2375a3f801f2962c3e41adb
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