Apart from removing almost 1000 lines of very repetitive code, the idea here is
to change the assembler from a huge pile of arbitrary code into something that
can be used to generate tables of opcodes and their structure. Later, I'd like to
use this to make the disassembler more table driven and less arbitrary, and
perhaps build an x86 simulator in the same vein as the ARM simulator, which
would help me debug (I find the ARM simulator very useful when making low level
changes to the VM and miss its functionality on x86).
R=vegorov@google.com
Bug:
Change-Id: I1ae2c1696f88b67862843c9ac05c827a7c9b9a6e
Reviewed-on: https://dart-review.googlesource.com/25241
Commit-Queue: Erik Corry <erikcorry@google.com>
Reviewed-by: Vyacheslav Egorov <vegorov@google.com>
Several tricks here:
* When zeroing registers we can use xorl instead of xorq because the 'l'
variant will zero the top bits.
* test and 'and' instructions with immediate arguments can use 8-bit and 32 bit
variants more heavily.
* mov reg, immediate can use more compact encodings when sign-extension is not
needed.
Performance is better than +1% when measured on Dart2JS.
R=vegorov@google.com
Intel optimization manual says: "Assembly/Compiler Coding Rule 64. (H impact, M
generality) Use the 32-bit versions of instructions in 64-bit mode to reduce
code size unless the 64-bit version is necessary to access 64-bit data or
additional registers."
Bug:
Change-Id: I2a989315c45f8d8ebab719653fbfa2b18ebb77c9
Reviewed-on: https://dart-review.googlesource.com/23400
Commit-Queue: Erik Corry <erikcorry@google.com>
Reviewed-by: Vyacheslav Egorov <vegorov@google.com>
R=vegorov@google.com
This removes the IA32 disassembler and uses the X64 disassembler for
both variants. Instructions that were in the IA32 assembler, but not
supported by the X64 disassembler have been added. It also adds some
regression tests for a lot of the disassembler output.
Bug:
Change-Id: I243abbb04c3a77810ce96ca74f7f42a5a1aea0cf
Reviewed-on: https://dart-review.googlesource.com/22982
Reviewed-by: Vyacheslav Egorov <vegorov@google.com>
Commit-Queue: Erik Corry <erikcorry@google.com>