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Date: Fri, 30 Jul 2004 18:11:00 -0000
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From: "steven at gcc dot gnu dot org" <gcc-bugzilla@gcc.gnu.org>
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Reply-To: gcc-bugzilla@gcc.gnu.org
Subject: [Bug tree-optimization/16797] Opportunity to remove unnecessary load instructions
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------- Additional Comments From steven at gcc dot gnu dot org  2004-07-30 18:11 -------
Interestingly, on AMD64 this test case doesn't even need a branch: 
 
foo: 
        movq    i(%rip), %rax		# %rax <-- i 
        sarq    $52, %rax		# %rax <-- (%rax >> 52) 
        movq    %rax, j(%rip)		# j <-- %rax 
        sarq    $11, %rax		# %rax <-- (%rax >> 11) 
        andq    $-10, %rax		# %rax <-- (%rax & -10) 
        addq    $20, %rax		# %rax <-- (%rax + 20) 
        movq    %rax, i(%rip)		# i <-- %rax 
        ret				# return %eax 
 

-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=16797