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From: "avi at scylladb dot com" <gcc-bugzilla@gcc.gnu.org>
To: gcc-bugs@gcc.gnu.org
Subject: [Bug tree-optimization/85516] [missed-optimization] gcc does not
 convert multiple compares against constants to a shift+bitmask test
Date: Mon, 29 Nov 2021 15:28:19 +0000
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https://gcc.gnu.org/bugzilla/show_bug.cgi?id=3D85516

--- Comment #6 from Avi Kivity <avi at scylladb dot com> ---
gcc 11.2 produces optimized code with the original example:

check_mask(E):
  cmpl $9, %edi
  ja .L3
  movl %edi, %ecx
  movl $562, %eax
  shrq %cl, %rax
  andl $1, %eax
  ret
.L3:
  xorl %eax, %eax
  ret=