; NOTE: Assertions have been autogenerated by utils/update_test_checks.py ; RUN: opt < %s -instcombine -S | FileCheck %s ; If we have a relational comparison with a constant, and said comparison is ; used in a select, and there is a constant in select, see if we can make ; those constants match. ; We can't ever get non-canonical scalar predicates. ; Likewise, while we can get non-canonical vector predicates, there must be an ; extra use on that `icmp`, which precludes the fold from happening. ;------------------------------------------------------------------------------; ; Canonical scalar predicates ;------------------------------------------------------------------------------; !0 = !{!"branch_weights", i32 2000, i32 1} define i32 @p0_ult_65536(i32 %x, i32 %y) { ; CHECK-LABEL: @p0_ult_65536( ; CHECK-NEXT: [[T_INV:%.*]] = icmp ugt i32 [[X:%.*]], 65535 ; CHECK-NEXT: [[R:%.*]] = select i1 [[T_INV]], i32 65535, i32 [[Y:%.*]], !prof !0 ; CHECK-NEXT: ret i32 [[R]] ; %t = icmp ult i32 %x, 65536 %r = select i1 %t, i32 %y, i32 65535, !prof !0 ret i32 %r } define i32 @p1_ugt(i32 %x, i32 %y) { ; CHECK-LABEL: @p1_ugt( ; CHECK-NEXT: [[T_INV:%.*]] = icmp ult i32 [[X:%.*]], 65535 ; CHECK-NEXT: [[R:%.*]] = select i1 [[T_INV]], i32 65535, i32 [[Y:%.*]] ; CHECK-NEXT: ret i32 [[R]] ; %t = icmp ugt i32 %x, 65534 %r = select i1 %t, i32 %y, i32 65535 ret i32 %r } define i32 @p2_slt_65536(i32 %x, i32 %y) { ; CHECK-LABEL: @p2_slt_65536( ; CHECK-NEXT: [[T_INV:%.*]] = icmp sgt i32 [[X:%.*]], 65535 ; CHECK-NEXT: [[R:%.*]] = select i1 [[T_INV]], i32 65535, i32 [[Y:%.*]] ; CHECK-NEXT: ret i32 [[R]] ; %t = icmp slt i32 %x, 65536 %r = select i1 %t, i32 %y, i32 65535 ret i32 %r } define i32 @p3_sgt(i32 %x, i32 %y) { ; CHECK-LABEL: @p3_sgt( ; CHECK-NEXT: [[T_INV:%.*]] = icmp slt i32 [[X:%.*]], 65535 ; CHECK-NEXT: [[R:%.*]] = select i1 [[T_INV]], i32 65535, i32 [[Y:%.*]] ; CHECK-NEXT: ret i32 [[R]] ; %t = icmp sgt i32 %x, 65534 %r = select i1 %t, i32 %y, i32 65535 ret i32 %r } ;------------------------------------------------------------------------------; ; Vectors ;------------------------------------------------------------------------------; define <2 x i32> @p4_vec_splat_ult_65536(<2 x i32> %x, <2 x i32> %y) { ; CHECK-LABEL: @p4_vec_splat_ult_65536( ; CHECK-NEXT: [[T_INV:%.*]] = icmp ugt <2 x i32> [[X:%.*]], ; CHECK-NEXT: [[R:%.*]] = select <2 x i1> [[T_INV]], <2 x i32> , <2 x i32> [[Y:%.*]] ; CHECK-NEXT: ret <2 x i32> [[R]] ; %t = icmp ult <2 x i32> %x, %r = select <2 x i1> %t, <2 x i32> %y, <2 x i32> ret <2 x i32> %r } define <2 x i32> @p5_vec_splat_ugt(<2 x i32> %x, <2 x i32> %y) { ; CHECK-LABEL: @p5_vec_splat_ugt( ; CHECK-NEXT: [[T_INV:%.*]] = icmp ult <2 x i32> [[X:%.*]], ; CHECK-NEXT: [[R:%.*]] = select <2 x i1> [[T_INV]], <2 x i32> , <2 x i32> [[Y:%.*]] ; CHECK-NEXT: ret <2 x i32> [[R]] ; %t = icmp ugt <2 x i32> %x, %r = select <2 x i1> %t, <2 x i32> %y, <2 x i32> ret <2 x i32> %r } define <2 x i32> @p6_vec_splat_slt_65536(<2 x i32> %x, <2 x i32> %y) { ; CHECK-LABEL: @p6_vec_splat_slt_65536( ; CHECK-NEXT: [[T_INV:%.*]] = icmp sgt <2 x i32> [[X:%.*]], ; CHECK-NEXT: [[R:%.*]] = select <2 x i1> [[T_INV]], <2 x i32> , <2 x i32> [[Y:%.*]] ; CHECK-NEXT: ret <2 x i32> [[R]] ; %t = icmp slt <2 x i32> %x, %r = select <2 x i1> %t, <2 x i32> %y, <2 x i32> ret <2 x i32> %r } define <2 x i32> @p7_vec_splat_sgt(<2 x i32> %x, <2 x i32> %y) { ; CHECK-LABEL: @p7_vec_splat_sgt( ; CHECK-NEXT: [[T_INV:%.*]] = icmp slt <2 x i32> [[X:%.*]], ; CHECK-NEXT: [[R:%.*]] = select <2 x i1> [[T_INV]], <2 x i32> , <2 x i32> [[Y:%.*]] ; CHECK-NEXT: ret <2 x i32> [[R]] ; %t = icmp sgt <2 x i32> %x, %r = select <2 x i1> %t, <2 x i32> %y, <2 x i32> ret <2 x i32> %r } ; Vectors with undef define <2 x i32> @p8_vec_nonsplat_undef0(<2 x i32> %x, <2 x i32> %y) { ; CHECK-LABEL: @p8_vec_nonsplat_undef0( ; CHECK-NEXT: [[T_INV:%.*]] = icmp ugt <2 x i32> [[X:%.*]], ; CHECK-NEXT: [[R:%.*]] = select <2 x i1> [[T_INV]], <2 x i32> , <2 x i32> [[Y:%.*]] ; CHECK-NEXT: ret <2 x i32> [[R]] ; %t = icmp ult <2 x i32> %x, %r = select <2 x i1> %t, <2 x i32> %y, <2 x i32> ret <2 x i32> %r } define <2 x i32> @p9_vec_nonsplat_undef1(<2 x i32> %x, <2 x i32> %y) { ; CHECK-LABEL: @p9_vec_nonsplat_undef1( ; CHECK-NEXT: [[T_INV:%.*]] = icmp ugt <2 x i32> [[X:%.*]], ; CHECK-NEXT: [[R:%.*]] = select <2 x i1> [[T_INV]], <2 x i32> , <2 x i32> [[Y:%.*]] ; CHECK-NEXT: ret <2 x i32> [[R]] ; %t = icmp ult <2 x i32> %x, %r = select <2 x i1> %t, <2 x i32> %y, <2 x i32> ret <2 x i32> %r } define <2 x i32> @p10_vec_nonsplat_undef2(<2 x i32> %x, <2 x i32> %y) { ; CHECK-LABEL: @p10_vec_nonsplat_undef2( ; CHECK-NEXT: [[T_INV:%.*]] = icmp ugt <2 x i32> [[X:%.*]], ; CHECK-NEXT: [[R:%.*]] = select <2 x i1> [[T_INV]], <2 x i32> , <2 x i32> [[Y:%.*]] ; CHECK-NEXT: ret <2 x i32> [[R]] ; %t = icmp ult <2 x i32> %x, %r = select <2 x i1> %t, <2 x i32> %y, <2 x i32> ret <2 x i32> %r } ; Non-splat vectors define <2 x i32> @p11_vec_nonsplat(<2 x i32> %x, <2 x i32> %y) { ; CHECK-LABEL: @p11_vec_nonsplat( ; CHECK-NEXT: [[T_INV:%.*]] = icmp ugt <2 x i32> [[X:%.*]], ; CHECK-NEXT: [[R:%.*]] = select <2 x i1> [[T_INV]], <2 x i32> , <2 x i32> [[Y:%.*]] ; CHECK-NEXT: ret <2 x i32> [[R]] ; %t = icmp ult <2 x i32> %x, %r = select <2 x i1> %t, <2 x i32> %y, <2 x i32> ret <2 x i32> %r } ;------------------------------------------------------------------------------; ; Extra uses prevent the fold. ;------------------------------------------------------------------------------; declare void @use1(i1) define i32 @n12_extrause(i32 %x, i32 %y) { ; CHECK-LABEL: @n12_extrause( ; CHECK-NEXT: [[T:%.*]] = icmp ult i32 [[X:%.*]], 65536 ; CHECK-NEXT: call void @use1(i1 [[T]]) ; CHECK-NEXT: [[R:%.*]] = select i1 [[T]], i32 [[Y:%.*]], i32 65535 ; CHECK-NEXT: ret i32 [[R]] ; %t = icmp ult i32 %x, 65536 call void @use1(i1 %t) %r = select i1 %t, i32 %y, i32 65535 ret i32 %r } ;------------------------------------------------------------------------------; ; Commutativity ;------------------------------------------------------------------------------; ; We don't care if the constant in select is true value or false value define i32 @p13_commutativity0(i32 %x, i32 %y) { ; CHECK-LABEL: @p13_commutativity0( ; CHECK-NEXT: [[T_INV:%.*]] = icmp ugt i32 [[X:%.*]], 65535 ; CHECK-NEXT: [[R:%.*]] = select i1 [[T_INV]], i32 [[Y:%.*]], i32 65535 ; CHECK-NEXT: ret i32 [[R]] ; %t = icmp ult i32 %x, 65536 %r = select i1 %t, i32 65535, i32 %y ret i32 %r } ; Which means, if both possibilities are constants, we must check both of them. define i32 @p14_commutativity1(i32 %x, i32 %y) { ; CHECK-LABEL: @p14_commutativity1( ; CHECK-NEXT: [[T_INV:%.*]] = icmp ugt i32 [[X:%.*]], 65535 ; CHECK-NEXT: [[R:%.*]] = select i1 [[T_INV]], i32 42, i32 65535 ; CHECK-NEXT: ret i32 [[R]] ; %t = icmp ult i32 %x, 65536 %r = select i1 %t, i32 65535, i32 42 ret i32 %r } define i32 @p15_commutativity2(i32 %x, i32 %y) { ; CHECK-LABEL: @p15_commutativity2( ; CHECK-NEXT: [[T_INV:%.*]] = icmp ugt i32 [[X:%.*]], 65535 ; CHECK-NEXT: [[R:%.*]] = select i1 [[T_INV]], i32 65535, i32 42 ; CHECK-NEXT: ret i32 [[R]] ; %t = icmp ult i32 %x, 65536 %r = select i1 %t, i32 42, i32 65535 ret i32 %r } ;------------------------------------------------------------------------------; ; Negative tests ;------------------------------------------------------------------------------; ; For vectors, make sure we handle edge cases correctly define <2 x i32> @n17_ult_zero(<2 x i32> %x, <2 x i32> %y) { ; CHECK-LABEL: @n17_ult_zero( ; CHECK-NEXT: [[T:%.*]] = icmp ult <2 x i32> [[X:%.*]], ; CHECK-NEXT: [[R:%.*]] = select <2 x i1> [[T]], <2 x i32> [[Y:%.*]], <2 x i32> ; CHECK-NEXT: ret <2 x i32> [[R]] ; %t = icmp ult <2 x i32> %x, %r = select <2 x i1> %t, <2 x i32> %y, <2 x i32> ret <2 x i32> %r } define <2 x i32> @n18_ugt_allones(<2 x i32> %x, <2 x i32> %y) { ; CHECK-LABEL: @n18_ugt_allones( ; CHECK-NEXT: [[T:%.*]] = icmp ugt <2 x i32> [[X:%.*]], ; CHECK-NEXT: [[R:%.*]] = select <2 x i1> [[T]], <2 x i32> [[Y:%.*]], <2 x i32> ; CHECK-NEXT: ret <2 x i32> [[R]] ; %t = icmp ugt <2 x i32> %x, %r = select <2 x i1> %t, <2 x i32> %y, <2 x i32> ret <2 x i32> %r } define <2 x i32> @n19_slt_int_min(<2 x i32> %x, <2 x i32> %y) { ; CHECK-LABEL: @n19_slt_int_min( ; CHECK-NEXT: [[T:%.*]] = icmp slt <2 x i32> [[X:%.*]], ; CHECK-NEXT: [[R:%.*]] = select <2 x i1> [[T]], <2 x i32> [[Y:%.*]], <2 x i32> ; CHECK-NEXT: ret <2 x i32> [[R]] ; %t = icmp slt <2 x i32> %x, %r = select <2 x i1> %t, <2 x i32> %y, <2 x i32> ret <2 x i32> %r } define <2 x i32> @n20_sgt_int_max(<2 x i32> %x, <2 x i32> %y) { ; CHECK-LABEL: @n20_sgt_int_max( ; CHECK-NEXT: [[T:%.*]] = icmp sgt <2 x i32> [[X:%.*]], ; CHECK-NEXT: [[R:%.*]] = select <2 x i1> [[T]], <2 x i32> [[Y:%.*]], <2 x i32> ; CHECK-NEXT: ret <2 x i32> [[R]] ; %t = icmp sgt <2 x i32> %x, %r = select <2 x i1> %t, <2 x i32> %y, <2 x i32> ret <2 x i32> %r } ; We don't do anything for non-relational comparisons. define i32 @n21_equality(i32 %x, i32 %y) { ; CHECK-LABEL: @n21_equality( ; CHECK-NEXT: [[T:%.*]] = icmp eq i32 [[X:%.*]], -2147483648 ; CHECK-NEXT: [[R:%.*]] = select i1 [[T]], i32 2147483647, i32 [[Y:%.*]] ; CHECK-NEXT: ret i32 [[R]] ; %t = icmp eq i32 %x, -2147483648 %r = select i1 %t, i32 2147483647, i32 %y ret i32 %r } ; There is nothing special about sign-bit-tests, we can fold them. define i32 @t22_sign_check(i32 %x, i32 %y) { ; CHECK-LABEL: @t22_sign_check( ; CHECK-NEXT: [[T_INV:%.*]] = icmp sgt i32 [[X:%.*]], -1 ; CHECK-NEXT: [[R:%.*]] = select i1 [[T_INV]], i32 [[Y:%.*]], i32 -1 ; CHECK-NEXT: ret i32 [[R]] ; %t = icmp slt i32 %x, 0 %r = select i1 %t, i32 -1, i32 %y ret i32 %r } define i32 @t22_sign_check2(i32 %x, i32 %y) { ; CHECK-LABEL: @t22_sign_check2( ; CHECK-NEXT: [[T_INV:%.*]] = icmp slt i32 [[X:%.*]], 0 ; CHECK-NEXT: [[R:%.*]] = select i1 [[T_INV]], i32 [[Y:%.*]], i32 0 ; CHECK-NEXT: ret i32 [[R]] ; %t = icmp sgt i32 %x, -1 %r = select i1 %t, i32 0, i32 %y ret i32 %r } ; If the types don't match we currently don't do anything. define i32 @n23_type_mismatch(i64 %x, i32 %y) { ; CHECK-LABEL: @n23_type_mismatch( ; CHECK-NEXT: [[T:%.*]] = icmp ult i64 [[X:%.*]], 65536 ; CHECK-NEXT: [[R:%.*]] = select i1 [[T]], i32 [[Y:%.*]], i32 65535 ; CHECK-NEXT: ret i32 [[R]] ; %t = icmp ult i64 %x, 65536 %r = select i1 %t, i32 %y, i32 65535 ret i32 %r } ; Don't do wrong tranform define i32 @n24_ult_65534(i32 %x, i32 %y) { ; CHECK-LABEL: @n24_ult_65534( ; CHECK-NEXT: [[T:%.*]] = icmp ult i32 [[X:%.*]], 65534 ; CHECK-NEXT: [[R:%.*]] = select i1 [[T]], i32 [[Y:%.*]], i32 65535 ; CHECK-NEXT: ret i32 [[R]] ; %t = icmp ult i32 %x, 65534 %r = select i1 %t, i32 %y, i32 65535 ret i32 %r } ; If we already have a match, it's good enough. define i32 @n25_all_good0(i32 %x, i32 %y) { ; CHECK-LABEL: @n25_all_good0( ; CHECK-NEXT: [[T:%.*]] = icmp ult i32 [[X:%.*]], 65536 ; CHECK-NEXT: [[R:%.*]] = select i1 [[T]], i32 65535, i32 65536 ; CHECK-NEXT: ret i32 [[R]] ; %t = icmp ult i32 %x, 65536 %r = select i1 %t, i32 65535, i32 65536 ret i32 %r } define i32 @n26_all_good1(i32 %x, i32 %y) { ; CHECK-LABEL: @n26_all_good1( ; CHECK-NEXT: [[T:%.*]] = icmp ult i32 [[X:%.*]], 65536 ; CHECK-NEXT: [[R:%.*]] = select i1 [[T]], i32 65536, i32 65535 ; CHECK-NEXT: ret i32 [[R]] ; %t = icmp ult i32 %x, 65536 %r = select i1 %t, i32 65536, i32 65535 ret i32 %r } ; CHECK: !0 = !{!"branch_weights", i32 1, i32 2000}