85 lines
		
	
	
		
			2.0 KiB
		
	
	
	
		
			LLVM
		
	
	
	
			
		
		
	
	
			85 lines
		
	
	
		
			2.0 KiB
		
	
	
	
		
			LLVM
		
	
	
	
; This test makes sure that these instructions are properly eliminated.
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;
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; RUN: opt < %s -instcombine -S | FileCheck %s
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; PR1253
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define i1 @test0(i32 %A) {
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; CHECK-LABEL: @test0(
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; CHECK: %C = icmp slt i32 %A, 0
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	%B = xor i32 %A, -2147483648
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	%C = icmp sgt i32 %B, -1
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	ret i1 %C
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}
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define i1 @test1(i32 %A) {
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; CHECK-LABEL: @test1(
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; CHECK: %C = icmp slt i32 %A, 0
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	%B = xor i32 %A, 12345
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	%C = icmp slt i32 %B, 0
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	ret i1 %C
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}
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; PR1014
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define i32 @test2(i32 %tmp1) {
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; CHECK-LABEL:      @test2(
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; CHECK-NEXT:   and i32 %tmp1, 32
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; CHECK-NEXT:   or i32 %ovm, 8 
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; CHECK-NEXT:   ret i32
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        %ovm = and i32 %tmp1, 32
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        %ov3 = add i32 %ovm, 145
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        %ov110 = xor i32 %ov3, 153
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        ret i32 %ov110
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}
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define i32 @test3(i32 %tmp1) {
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; CHECK-LABEL:      @test3(
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; CHECK-NEXT:   and i32 %tmp1, 32
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; CHECK-NEXT:   or i32 %ovm, 8
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; CHECK-NEXT:   ret i32
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  %ovm = or i32 %tmp1, 145 
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  %ov31 = and i32 %ovm, 177
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  %ov110 = xor i32 %ov31, 153
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  ret i32 %ov110
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}
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define i32 @test4(i32 %A, i32 %B) {
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	%1 = xor i32 %A, -1
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	%2 = ashr i32 %1, %B
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	%3 = xor i32 %2, -1
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	ret i32 %3
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; CHECK-LABEL: @test4(
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; CHECK: %1 = ashr i32 %A, %B
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; CHECK: ret i32 %1
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}
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; defect-2 in rdar://12329730
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; (X^C1) >> C2) ^ C3 -> (X>>C2) ^ ((C1>>C2)^C3)
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;   where the "X" has more than one use
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define i32 @test5(i32 %val1) {
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test5:
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  %xor = xor i32 %val1, 1234
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  %shr = lshr i32 %xor, 8
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  %xor1 = xor i32 %shr, 1
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  %add = add i32 %xor1, %xor
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  ret i32 %add
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; CHECK-LABEL: @test5(
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; CHECK: lshr i32 %val1, 8
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; CHECK: ret
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}
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; defect-1 in rdar://12329730
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; Simplify (X^Y) -> X or Y in the user's context if we know that 
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; only bits from X or Y are demanded.
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; e.g. the "x ^ 1234" can be optimized into x in the context of "t >> 16".
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;  Put in other word, t >> 16 -> x >> 16.
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; unsigned foo(unsigned x) { unsigned t = x ^ 1234; ;  return (t >> 16) + t;}
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define i32 @test6(i32 %x) {
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  %xor = xor i32 %x, 1234
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  %shr = lshr i32 %xor, 16
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  %add = add i32 %shr, %xor
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  ret i32 %add
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; CHECK-LABEL: @test6(
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; CHECK: lshr i32 %x, 16
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; CHECK: ret
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}
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