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llvm-project/llvm/test/Analysis/ScalarEvolution/xor-and.ll

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Teach ScalarEvolution how to recognize another xor(and(x, C), C) case. If C is a single bit and the and gets analyzed as a truncate and zero-extend, the xor can be represnted as an add. llvm-svn: 73664
2009-06-18 08:00:20 +08:00
; RUN: llvm-as < %s | opt -scalar-evolution -disable-output -analyze \
; RUN: | grep {\\--> (zext i4 (-8 + (trunc i64 (8 \\* %x) to i4)) to i64)}
Fix ScalarEvolution's Xor handling to not assume that an And that gets recognized with a SCEVZeroExtendExpr must be an And with a low-bits mask. With r73540, this is no longer the case. llvm-svn: 73594
2009-06-17 09:22:39 +08:00
Teach ScalarEvolution how to recognize another xor(and(x, C), C) case. If C is a single bit and the and gets analyzed as a truncate and zero-extend, the xor can be represnted as an add. llvm-svn: 73664
2009-06-18 08:00:20 +08:00
; ScalarEvolution shouldn't try to analyze %z into something like
Fix ScalarEvolution's Xor handling to not assume that an And that gets recognized with a SCEVZeroExtendExpr must be an And with a low-bits mask. With r73540, this is no longer the case. llvm-svn: 73594
2009-06-17 09:22:39 +08:00
; --> (zext i4 (-1 + (-1 * (trunc i64 (8 * %x) to i4))) to i64)
define i64 @foo(i64 %x) {
%a = shl i64 %x, 3
%t = and i64 %a, 8
%z = xor i64 %t, 8
ret i64 %z
}