On 8/2/21 2:18 PM, Maciej W. Rozycki wrote: > On Mon, 2 Aug 2021, Philippe Mathieu-Daudé wrote: > >>> Per the "Godson-2E User Manual v0.6", the Loongson 2E processor >>> does not implement the MOVZ/MOVN instructions >> >> I'm confused because I can't find MOVZ/MOVN in the 2E manual and >> the 2F explicits the difference. However looking at binutils, >> these opcodes are also emited on the 2E: >> https://sourceware.org/git/?p=binutils-gdb.git;a=commitdiff;h=350cc38db21f1cd651a6d46687542a0fce5e0303;hp=569502941afa825c5278b320ccedeefc82e8ed0e > > I find the manual a bit messy. It does say however: > > "3.2.3 Instruction set mode > > "Godson-2E processor implements a full feature MIPS III Instruction Set > Architecture (ISA) plus some MIPS IV ISA instructions, like paired single, > move condition and multiply add." > >> Cc'ing Mark & Maciej in case they can enlighten me, and few >> Loongson develeper in case they could check, because I don't >> have 2E hardware to test. > > At least this trivial program: > > int main(void) > { > asm volatile(".set push; .set mips4; movn $0,$0,$0; .set pop"); > return 0; > } > > does not trap on actual hardware.
Thank you very much for your time and testing! > I may not be able to find time right > now for a more exhaustive test. This is fine for me now, I'll add documentation to justify while the the documentation doesn't describe MOVZ/MOVN, it mentions "implements MIPS IV ISA instructions like move condition" so we assume they are, also with your test not trapping. Regards, Phil.
