; RUN: opt -S -instcombine < %s | FileCheck %s
declare void @use(i8)
+declare void @use.i1(i1)
+declare i8 @llvm.umin.i8(i8, i8)
define i1 @icmp_select_const(i8 %x, i8 %y) {
; CHECK-LABEL: @icmp_select_const(
%cmp2 = icmp uge i8 %z1, %sel
ret i1 %cmp2
}
+
+define i1 @icmp_select_implied_cond(i8 %x, i8 %y) {
+; CHECK-LABEL: @icmp_select_implied_cond(
+; CHECK-NEXT: [[CMP1:%.*]] = icmp eq i8 [[X:%.*]], 0
+; CHECK-NEXT: [[SEL:%.*]] = select i1 [[CMP1]], i8 0, i8 [[Y:%.*]]
+; CHECK-NEXT: [[CMP2:%.*]] = icmp eq i8 [[SEL]], [[X]]
+; CHECK-NEXT: ret i1 [[CMP2]]
+;
+ %cmp1 = icmp eq i8 %x, 0
+ %sel = select i1 %cmp1, i8 0, i8 %y
+ %cmp2 = icmp eq i8 %sel, %x
+ ret i1 %cmp2
+}
+
+define i1 @icmp_select_implied_cond_ne(i8 %x, i8 %y) {
+; CHECK-LABEL: @icmp_select_implied_cond_ne(
+; CHECK-NEXT: [[CMP1:%.*]] = icmp eq i8 [[X:%.*]], 0
+; CHECK-NEXT: [[SEL:%.*]] = select i1 [[CMP1]], i8 0, i8 [[Y:%.*]]
+; CHECK-NEXT: [[CMP2:%.*]] = icmp ne i8 [[SEL]], [[X]]
+; CHECK-NEXT: ret i1 [[CMP2]]
+;
+ %cmp1 = icmp eq i8 %x, 0
+ %sel = select i1 %cmp1, i8 0, i8 %y
+ %cmp2 = icmp ne i8 %sel, %x
+ ret i1 %cmp2
+}
+
+define i1 @icmp_select_implied_cond_swapped_select(i8 %x, i8 %y) {
+; CHECK-LABEL: @icmp_select_implied_cond_swapped_select(
+; CHECK-NEXT: [[CMP1:%.*]] = icmp eq i8 [[X:%.*]], 0
+; CHECK-NEXT: [[SEL:%.*]] = select i1 [[CMP1]], i8 [[Y:%.*]], i8 0
+; CHECK-NEXT: [[CMP2:%.*]] = icmp eq i8 [[SEL]], [[X]]
+; CHECK-NEXT: ret i1 [[CMP2]]
+;
+ %cmp1 = icmp eq i8 %x, 0
+ %sel = select i1 %cmp1, i8 %y, i8 0
+ %cmp2 = icmp eq i8 %sel, %x
+ ret i1 %cmp2
+}
+
+define i1 @icmp_select_implied_cond_swapped_select_with_inv_cond(i8 %x, i8 %y) {
+; CHECK-LABEL: @icmp_select_implied_cond_swapped_select_with_inv_cond(
+; CHECK-NEXT: [[CMP1:%.*]] = icmp ne i8 [[X:%.*]], 0
+; CHECK-NEXT: call void @use.i1(i1 [[CMP1]])
+; CHECK-NEXT: [[SEL:%.*]] = select i1 [[CMP1]], i8 [[Y:%.*]], i8 0
+; CHECK-NEXT: [[CMP2:%.*]] = icmp eq i8 [[SEL]], [[X]]
+; CHECK-NEXT: ret i1 [[CMP2]]
+;
+ %cmp1 = icmp ne i8 %x, 0
+ call void @use.i1(i1 %cmp1)
+ %sel = select i1 %cmp1, i8 %y, i8 0
+ %cmp2 = icmp eq i8 %sel, %x
+ ret i1 %cmp2
+}
+
+define i1 @icmp_select_implied_cond_relational(i8 %x, i8 %y) {
+; CHECK-LABEL: @icmp_select_implied_cond_relational(
+; CHECK-NEXT: [[CMP1:%.*]] = icmp ugt i8 [[X:%.*]], 10
+; CHECK-NEXT: [[SEL:%.*]] = select i1 [[CMP1]], i8 10, i8 [[Y:%.*]]
+; CHECK-NEXT: [[CMP2:%.*]] = icmp ult i8 [[SEL]], [[X]]
+; CHECK-NEXT: ret i1 [[CMP2]]
+;
+ %cmp1 = icmp ugt i8 %x, 10
+ %sel = select i1 %cmp1, i8 10, i8 %y
+ %cmp2 = icmp ult i8 %sel, %x
+ ret i1 %cmp2
+}
+
+define i1 @icmp_select_implied_cond_relational_off_by_one(i8 %x, i8 %y) {
+; CHECK-LABEL: @icmp_select_implied_cond_relational_off_by_one(
+; CHECK-NEXT: [[CMP1:%.*]] = icmp ugt i8 [[X:%.*]], 10
+; CHECK-NEXT: call void @use.i1(i1 [[CMP1]])
+; CHECK-NEXT: [[SEL:%.*]] = select i1 [[CMP1]], i8 11, i8 [[Y:%.*]]
+; CHECK-NEXT: [[CMP2:%.*]] = icmp ult i8 [[SEL]], [[X]]
+; CHECK-NEXT: ret i1 [[CMP2]]
+;
+ %cmp1 = icmp ugt i8 %x, 10
+ call void @use.i1(i1 %cmp1)
+ %sel = select i1 %cmp1, i8 11, i8 %y
+ %cmp2 = icmp ult i8 %sel, %x
+ ret i1 %cmp2
+}
+
+define i1 @umin_seq_comparison(i8 %x, i8 %y) {
+; CHECK-LABEL: @umin_seq_comparison(
+; CHECK-NEXT: [[MIN:%.*]] = call i8 @llvm.umin.i8(i8 [[X:%.*]], i8 [[Y:%.*]])
+; CHECK-NEXT: [[CMP1:%.*]] = icmp eq i8 [[X]], 0
+; CHECK-NEXT: [[SEL:%.*]] = select i1 [[CMP1]], i8 0, i8 [[MIN]]
+; CHECK-NEXT: [[CMP2:%.*]] = icmp eq i8 [[SEL]], [[X]]
+; CHECK-NEXT: ret i1 [[CMP2]]
+;
+ %min = call i8 @llvm.umin.i8(i8 %x, i8 %y)
+ %cmp1 = icmp eq i8 %x, 0
+ %sel = select i1 %cmp1, i8 0, i8 %min
+ %cmp2 = icmp eq i8 %sel, %x
+ ret i1 %cmp2
+}