Stream: git-cranelift

Topic: cranelift / Issue #1309 Determine cause of crash with inf...

view this post on Zulip GitHub (Dec 22 2019 at 06:14):

sstangl opened Issue #1309:

Reported in https://github.com/bytecodealliance/cranelift/issues/1305 and fixed (by partially reverting a patch in https://github.com/bytecodealliance/cranelift/pull/1308), it appears that when brz and brnz are emitted with runtime-inferred REX prefixes (and therefore don't have constant instruction size), the code can jump into the middle of nowhere.

https://github.com/bytecodealliance/cranelift/pull/1308 changed brz and brnz back to using separate encodings for REX and non-REX to prevent crashes in the meantime. This issue is to find the cause and fix it.

STR are in https://github.com/bytecodealliance/cranelift/issues/1305 but I was not able to reproduce it locally.

view this post on Zulip GitHub (Dec 22 2019 at 06:14):

sstangl labeled Issue #1309:

Reported in https://github.com/bytecodealliance/cranelift/issues/1305 and fixed (by partially reverting a patch in https://github.com/bytecodealliance/cranelift/pull/1308), it appears that when brz and brnz are emitted with runtime-inferred REX prefixes (and therefore don't have constant instruction size), the code can jump into the middle of nowhere.

https://github.com/bytecodealliance/cranelift/pull/1308 changed brz and brnz back to using separate encodings for REX and non-REX to prevent crashes in the meantime. This issue is to find the cause and fix it.

STR are in https://github.com/bytecodealliance/cranelift/issues/1305 but I was not able to reproduce it locally.

view this post on Zulip GitHub (Feb 28 2020 at 23:28):

alexcrichton transferred Issue #1309:

Reported in https://github.com/bytecodealliance/cranelift/issues/1305 and fixed (by partially reverting a patch in https://github.com/bytecodealliance/cranelift/pull/1308), it appears that when brz and brnz are emitted with runtime-inferred REX prefixes (and therefore don't have constant instruction size), the code can jump into the middle of nowhere.

https://github.com/bytecodealliance/cranelift/pull/1308 changed brz and brnz back to using separate encodings for REX and non-REX to prevent crashes in the meantime. This issue is to find the cause and fix it.

STR are in https://github.com/bytecodealliance/cranelift/issues/1305 but I was not able to reproduce it locally.

Last updated: Dec 06 2025 at 06:05 UTC