MIPS extension support - Toshiba TX19A/TX39

[notxvilka]

Feature

• [ ] New architecture module
• [x] Support for processor extension
• [ ] Add more instruction details (elaborated below)
• [ ] Binding support for: language
• [ ] Other (elaborated below)

Describe the feature you'd like

Toshiba TX19a (little and big endian) - The 16-bit ISA mode instructions are compatible with the MIPS16e-TX instructions. The 32-bit ISA mode instructions are compatible with the TX39 instructions. TX39 instructions are derived from MIPS R3000A.

Additional context

• http://www.bitsavers.org/components/toshiba/_dataSheet/TMPR39xx-um_199507.pdf
• https://wiki.qemu.org/images/d/d2/DSAE0022432.pdf
• https://ecos.sourceware.org/ecos/docs-latest/user-guide/setup-tx39-sim.html
• https://toshiba.semicon-storage.com/info/TMP19A64C1DXBG_datasheet_en_20070316.pdf?did=9949&prodName=TMP19A64C1DXBG

[jelly8173]

Afaik those MIPS16 R3000A instructions is an issue for at least 8 years, here its implementation for IDA: https://github.com/simeonpilgrim/nikon-firmware-tools/blob/1d45dbf63ced61da612aef03334ec5314b7c6af6/Tx19a%20IDA%20Plugin/TX19Av2.cpp

[Rot127]

@jelly8173 Do you have some bytes to asm-text mapping we can try out?