Re: [x86 PATCH] Improve reg pressure of double-word right-shift then truncate.

2023-11-12 Thread Uros Bizjak
On Sun, Nov 12, 2023 at 10:03 PM Roger Sayle wrote: > > > This patch improves register pressure during reload, inspired by PR 97756. > Normally, a double-word right-shift by a constant produces a double-word > result, the highpart of which is dead when followed by a truncation. > The dead code

[x86 PATCH] Improve reg pressure of double-word right-shift then truncate.

2023-11-12 Thread Roger Sayle
This patch improves register pressure during reload, inspired by PR 97756. Normally, a double-word right-shift by a constant produces a double-word result, the highpart of which is dead when followed by a truncation. The dead code calculating the high part gets cleaned up post-reload, so the