[PATCH] D69979: clang: Guess at some platform FTZ/DAZ default settings

Fri Nov 8 05:19:29 PST 2019

spatel added a comment.

In D69979#1738099 <https://reviews.llvm.org/D69979#1738099>, @craig.topper wrote:

> I checked Redhat 7.4 that's on the server I'm using for work. And I had a coworker check his Ubuntu 18.04 system with this program. And both systems printed 1f80 as the value of MXCSR which shows FTZ and DAZ are both 0. Are you seeing something different?

AFAIK, x86(-64) Linux is IEEE-compliant by default. It's only when compiling with -ffast-math that clang/gcc link in the startup routine to set FTZ/DAZ. So this patch should use that same mechanism to set the denorm mode. See: 
https://reviews.llvm.org/rL165240

@RKSimon - is it the same on PS4?

CHANGES SINCE LAST ACTION
  https://reviews.llvm.org/D69979/new/

https://reviews.llvm.org/D69979