mirrors/cosmopolitan
1
0
Fork 0
mirror of https://github.com/jart/cosmopolitan.git synced 2025-07-03 01:38:30 +00:00
Code Issues Projects Releases Packages Wiki Activity Actions

Add x86_64-linux-gnu emulator

Browse source 
I wanted a tiny scriptable meltdown proof way to run userspace programs
and visualize how program execution impacts memory. It helps to explain
how things like Actually Portable Executable works. It can show you how
the GCC generated code is going about manipulating matrices and more. I
didn't feel fully comfortable with Qemu and Bochs because I'm not smart
enough to understand them. I wanted something like gVisor but with much
stronger levels of assurances. I wanted a single binary that'll run, on
all major operating systems with an embedded GPL barrier ZIP filesystem
that is tiny enough to transpile to JavaScript and run in browsers too.

https://justine.storage.googleapis.com/emulator625.mp4
This commit is contained in:
Justine Tunney 2020-08-25 04:23:25 -07:00
parent 467504308a
commit f4f4caab0e
1052 changed files with 65667 additions and 7825 deletions
Download patch file Download diff file Expand all files Collapse all files

9
libc/nexgen32e/tinydivsi.greg.S
View file

@ -21,17 +21,22 @@
/ Support code for fast integer division by Si units.
/
/ Division by magnums is described in Hacker's Delight and is
/ usually generated automatically by compilers, but sadly not
/ when we optimize for size and idiv goes at least 10x slower
/ so we do this which saves space while avoiding build tuning
/
/ @param rdi is number to divide
/ @param cl is magnum #1
/ @param rdx is magnum #2
/ @return truncated numerator
/ @return quotient
tinydivsi:
.leafprologue
mov %rdi,%rax
imul %rdx
mov %rdx,%rax
sar %cl,%rax
sar $0x3f,%rdi
sar $63,%rdi
sub %rdi,%rax
.leafepilogue
.endfn tinydivsi,globl