; NOTE: Assertions have been autogenerated by utils/update_test_checks.py ; RUN: opt < %s -instcombine -S | FileCheck %s ; If we have a masked merge, in the form of: (M is constant) ; ((x ^ y) & M) ^ y ; Unfold it to ; (x & M) | (y & ~M) define i4 @scalar0 (i4 %x, i4 %y) { ; CHECK-LABEL: @scalar0( ; CHECK-NEXT: [[TMP1:%.*]] = and i4 [[X:%.*]], 1 ; CHECK-NEXT: [[TMP2:%.*]] = and i4 [[Y:%.*]], -2 ; CHECK-NEXT: [[R:%.*]] = or i4 [[TMP1]], [[TMP2]] ; CHECK-NEXT: ret i4 [[R]] ; %n0 = xor i4 %x, %y %n1 = and i4 %n0, 1 %r = xor i4 %n1, %y ret i4 %r } define i4 @scalar1 (i4 %x, i4 %y) { ; CHECK-LABEL: @scalar1( ; CHECK-NEXT: [[TMP1:%.*]] = and i4 [[X:%.*]], -2 ; CHECK-NEXT: [[TMP2:%.*]] = and i4 [[Y:%.*]], 1 ; CHECK-NEXT: [[R:%.*]] = or i4 [[TMP1]], [[TMP2]] ; CHECK-NEXT: ret i4 [[R]] ; %n0 = xor i4 %x, %y %n1 = and i4 %n0, -2 %r = xor i4 %n1, %y ret i4 %r } ; ============================================================================ ; ; Various cases with %x and/or %y being a constant ; ============================================================================ ; define i4 @in_constant_varx_mone(i4 %x, i4 %mask) { ; CHECK-LABEL: @in_constant_varx_mone( ; CHECK-NEXT: [[R1:%.*]] = or i4 [[X:%.*]], -2 ; CHECK-NEXT: ret i4 [[R1]] ; %n0 = xor i4 %x, -1 ; %x %n1 = and i4 %n0, 1 %r = xor i4 %n1, -1 ret i4 %r } define i4 @in_constant_varx_14(i4 %x, i4 %mask) { ; CHECK-LABEL: @in_constant_varx_14( ; CHECK-NEXT: [[R1:%.*]] = or i4 [[X:%.*]], -2 ; CHECK-NEXT: ret i4 [[R1]] ; %n0 = xor i4 %x, 14 ; %x %n1 = and i4 %n0, 1 %r = xor i4 %n1, 14 ret i4 %r } define i4 @in_constant_mone_vary(i4 %y, i4 %mask) { ; CHECK-LABEL: @in_constant_mone_vary( ; CHECK-NEXT: [[R1:%.*]] = or i4 [[Y:%.*]], 1 ; CHECK-NEXT: ret i4 [[R1]] ; %n0 = xor i4 %y, -1 ; %x %n1 = and i4 %n0, 1 %r = xor i4 %n1, %y ret i4 %r } define i4 @in_constant_14_vary(i4 %y, i4 %mask) { ; CHECK-LABEL: @in_constant_14_vary( ; CHECK-NEXT: [[R:%.*]] = and i4 [[Y:%.*]], -2 ; CHECK-NEXT: ret i4 [[R]] ; %n0 = xor i4 %y, 14 ; %x %n1 = and i4 %n0, 1 %r = xor i4 %n1, %y ret i4 %r } ; ============================================================================ ; ; Commutativity ; ============================================================================ ; ; Used to make sure that the IR complexity sorting does not interfere. declare i4 @gen4() define i4 @c_1_0_0 (i4 %x, i4 %y) { ; CHECK-LABEL: @c_1_0_0( ; CHECK-NEXT: [[TMP1:%.*]] = and i4 [[X:%.*]], -2 ; CHECK-NEXT: [[TMP2:%.*]] = and i4 [[Y:%.*]], 1 ; CHECK-NEXT: [[R:%.*]] = or i4 [[TMP1]], [[TMP2]] ; CHECK-NEXT: ret i4 [[R]] ; %n0 = xor i4 %y, %x ; swapped order %n1 = and i4 %n0, -2 %r = xor i4 %n1, %y ret i4 %r } define i4 @c_0_1_0 (i4 %x, i4 %y) { ; CHECK-LABEL: @c_0_1_0( ; CHECK-NEXT: [[TMP1:%.*]] = and i4 [[Y:%.*]], -2 ; CHECK-NEXT: [[TMP2:%.*]] = and i4 [[X:%.*]], 1 ; CHECK-NEXT: [[R:%.*]] = or i4 [[TMP1]], [[TMP2]] ; CHECK-NEXT: ret i4 [[R]] ; %n0 = xor i4 %x, %y %n1 = and i4 %n0, -2 %r = xor i4 %n1, %x ; %x instead of %y ret i4 %r } define i4 @c_0_0_1 () { ; CHECK-LABEL: @c_0_0_1( ; CHECK-NEXT: [[X:%.*]] = call i4 @gen4() ; CHECK-NEXT: [[Y:%.*]] = call i4 @gen4() ; CHECK-NEXT: [[TMP1:%.*]] = and i4 [[X]], -2 ; CHECK-NEXT: [[TMP2:%.*]] = and i4 [[Y]], 1 ; CHECK-NEXT: [[R:%.*]] = or i4 [[TMP1]], [[TMP2]] ; CHECK-NEXT: ret i4 [[R]] ; %x = call i4 @gen4() %y = call i4 @gen4() %n0 = xor i4 %x, %y %n1 = and i4 %n0, -2 %r = xor i4 %y, %n1 ; swapped order ret i4 %r } define i4 @c_1_1_0 (i4 %x, i4 %y) { ; CHECK-LABEL: @c_1_1_0( ; CHECK-NEXT: [[TMP1:%.*]] = and i4 [[Y:%.*]], -2 ; CHECK-NEXT: [[TMP2:%.*]] = and i4 [[X:%.*]], 1 ; CHECK-NEXT: [[R:%.*]] = or i4 [[TMP1]], [[TMP2]] ; CHECK-NEXT: ret i4 [[R]] ; %n0 = xor i4 %y, %x ; swapped order %n1 = and i4 %n0, -2 %r = xor i4 %n1, %x ; %x instead of %y ret i4 %r } define i4 @c_1_0_1 (i4 %x) { ; CHECK-LABEL: @c_1_0_1( ; CHECK-NEXT: [[Y:%.*]] = call i4 @gen4() ; CHECK-NEXT: [[TMP1:%.*]] = and i4 [[X:%.*]], -2 ; CHECK-NEXT: [[TMP2:%.*]] = and i4 [[Y]], 1 ; CHECK-NEXT: [[R:%.*]] = or i4 [[TMP1]], [[TMP2]] ; CHECK-NEXT: ret i4 [[R]] ; %y = call i4 @gen4() %n0 = xor i4 %y, %x ; swapped order %n1 = and i4 %n0, -2 %r = xor i4 %y, %n1 ; swapped order ret i4 %r } define i4 @c_0_1_1 (i4 %y) { ; CHECK-LABEL: @c_0_1_1( ; CHECK-NEXT: [[X:%.*]] = call i4 @gen4() ; CHECK-NEXT: [[TMP1:%.*]] = and i4 [[Y:%.*]], -2 ; CHECK-NEXT: [[TMP2:%.*]] = and i4 [[X]], 1 ; CHECK-NEXT: [[R:%.*]] = or i4 [[TMP1]], [[TMP2]] ; CHECK-NEXT: ret i4 [[R]] ; %x = call i4 @gen4() %n0 = xor i4 %x, %y %n1 = and i4 %n0, -2 %r = xor i4 %x, %n1 ; swapped order, %x instead of %y ret i4 %r } define i4 @c_1_1_1 () { ; CHECK-LABEL: @c_1_1_1( ; CHECK-NEXT: [[X:%.*]] = call i4 @gen4() ; CHECK-NEXT: [[Y:%.*]] = call i4 @gen4() ; CHECK-NEXT: [[TMP1:%.*]] = and i4 [[Y]], -2 ; CHECK-NEXT: [[TMP2:%.*]] = and i4 [[X]], 1 ; CHECK-NEXT: [[R:%.*]] = or i4 [[TMP1]], [[TMP2]] ; CHECK-NEXT: ret i4 [[R]] ; %x = call i4 @gen4() %y = call i4 @gen4() %n0 = xor i4 %y, %x ; swapped order %n1 = and i4 %n0, -2 %r = xor i4 %x, %n1 ; swapped order, %x instead of %y ret i4 %r } define i4 @commutativity_constant_14_vary(i4 %y, i4 %mask) { ; CHECK-LABEL: @commutativity_constant_14_vary( ; CHECK-NEXT: [[R:%.*]] = and i4 [[Y:%.*]], -2 ; CHECK-NEXT: ret i4 [[R]] ; %n0 = xor i4 %y, 14 ; %x %n1 = and i4 %n0, 1 %r = xor i4 %y, %n1 ; swapped ret i4 %r } ; ============================================================================ ; ; Negative tests. Should not be folded. ; ============================================================================ ; ; One use only. declare void @use4(i4) define i4 @n_oneuse_D (i4 %x, i4 %y) { ; CHECK-LABEL: @n_oneuse_D( ; CHECK-NEXT: [[N0:%.*]] = xor i4 [[X:%.*]], [[Y:%.*]] ; CHECK-NEXT: [[N1:%.*]] = and i4 [[N0]], -2 ; CHECK-NEXT: [[R:%.*]] = xor i4 [[N1]], [[Y]] ; CHECK-NEXT: call void @use4(i4 [[N0]]) ; CHECK-NEXT: ret i4 [[R]] ; %n0 = xor i4 %x, %y ; two uses of %n0, which is going to be replaced %n1 = and i4 %n0, -2 %r = xor i4 %n1, %y call void @use4(i4 %n0) ret i4 %r } define i4 @n_oneuse_A (i4 %x, i4 %y) { ; CHECK-LABEL: @n_oneuse_A( ; CHECK-NEXT: [[N0:%.*]] = xor i4 [[X:%.*]], [[Y:%.*]] ; CHECK-NEXT: [[N1:%.*]] = and i4 [[N0]], -2 ; CHECK-NEXT: [[R:%.*]] = xor i4 [[N1]], [[Y]] ; CHECK-NEXT: call void @use4(i4 [[N1]]) ; CHECK-NEXT: ret i4 [[R]] ; %n0 = xor i4 %x, %y %n1 = and i4 %n0, -2 ; two uses of %n1, which is going to be replaced %r = xor i4 %n1, %y call void @use4(i4 %n1) ret i4 %r } define i4 @n_oneuse_AD (i4 %x, i4 %y) { ; CHECK-LABEL: @n_oneuse_AD( ; CHECK-NEXT: [[N0:%.*]] = xor i4 [[X:%.*]], [[Y:%.*]] ; CHECK-NEXT: [[N1:%.*]] = and i4 [[N0]], -2 ; CHECK-NEXT: [[R:%.*]] = xor i4 [[N1]], [[Y]] ; CHECK-NEXT: call void @use4(i4 [[N0]]) ; CHECK-NEXT: call void @use4(i4 [[N1]]) ; CHECK-NEXT: ret i4 [[R]] ; %n0 = xor i4 %x, %y %n1 = and i4 %n0, -2 ; two uses of %n1, which is going to be replaced %r = xor i4 %n1, %y call void @use4(i4 %n0) call void @use4(i4 %n1) ret i4 %r } ; Mask is not constant define i4 @n_var_mask (i4 %x, i4 %y, i4 %m) { ; CHECK-LABEL: @n_var_mask( ; CHECK-NEXT: [[N0:%.*]] = xor i4 [[X:%.*]], [[Y:%.*]] ; CHECK-NEXT: [[N1:%.*]] = and i4 [[N0]], [[M:%.*]] ; CHECK-NEXT: [[R:%.*]] = xor i4 [[N1]], [[Y]] ; CHECK-NEXT: ret i4 [[R]] ; %n0 = xor i4 %x, %y %n1 = and i4 %n0, %m %r = xor i4 %n1, %y ret i4 %r } ; Some third variable is used define i4 @n_third_var (i4 %x, i4 %y, i4 %z) { ; CHECK-LABEL: @n_third_var( ; CHECK-NEXT: [[N0:%.*]] = xor i4 [[X:%.*]], [[Y:%.*]] ; CHECK-NEXT: [[N1:%.*]] = and i4 [[N0]], -2 ; CHECK-NEXT: [[R:%.*]] = xor i4 [[N1]], [[Z:%.*]] ; CHECK-NEXT: ret i4 [[R]] ; %n0 = xor i4 %x, %y %n1 = and i4 %n0, -2 %r = xor i4 %n1, %z ; not %x or %y ret i4 %r }