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34 lines
715 B
Plaintext
34 lines
715 B
Plaintext
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%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
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Fix Ordered/Unordered FP stuff
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%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
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improve bytezap opertunities
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ulong %foo(ulong %y) {
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entry:
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%tmp = and ulong %y, 65535
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%tmp2 = shr ulong %tmp, ubyte 3
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ret ulong %tmp2
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}
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compiles to a 3 instruction sequence without instcombine
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zapnot $16,3,$0
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srl $0,3,$0
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ret $31,($26),1
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After instcombine you get
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ulong %foo(ulong %y) {
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entry:
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%tmp = shr ulong %y, ubyte 3 ; <ulong> [#uses=1]
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%tmp2 = and ulong %tmp, 8191 ; <ulong> [#uses=1]
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ret ulong %tmp2
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}
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which compiles to
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lda $0,8191($31)
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srl $16,3,$1
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and $1,$0,$0
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ret $31,($26),1
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