; NOTE: Assertions have been autogenerated by utils/update_test_checks.py ; RUN: opt -S -instcombine < %s | FileCheck %s define i16 @foo(i16 %x) { ; CHECK-LABEL: @foo( ; CHECK-NEXT: [[T1:%.*]] = and i16 [[X:%.*]], 255 ; CHECK-NEXT: ret i16 [[T1]] ; %t1 = and i16 %x, 255 %t2 = zext i16 %t1 to i32 %t3 = icmp ult i32 %t2, 255 %t4 = select i1 %t3, i32 %t2, i32 255 %t5 = trunc i32 %t4 to i16 %t6 = and i16 %t5, 255 ret i16 %t6 } ; This contains a min/max pair to clamp a value to 12 bits. ; By analyzing the clamp pattern, we can tell the add doesn't have signed overflow. define i16 @min_max_clamp(i16 %x) { ; CHECK-LABEL: @min_max_clamp( ; CHECK-NEXT: [[A:%.*]] = icmp sgt i16 [[X:%.*]], -2048 ; CHECK-NEXT: [[B:%.*]] = select i1 [[A]], i16 [[X]], i16 -2048 ; CHECK-NEXT: [[C:%.*]] = icmp slt i16 [[B]], 2047 ; CHECK-NEXT: [[D:%.*]] = select i1 [[C]], i16 [[B]], i16 2047 ; CHECK-NEXT: [[E:%.*]] = add nsw i16 [[D]], 1 ; CHECK-NEXT: ret i16 [[E]] ; %a = icmp sgt i16 %x, -2048 %b = select i1 %a, i16 %x, i16 -2048 %c = icmp slt i16 %b, 2047 %d = select i1 %c, i16 %b, i16 2047 %e = add i16 %d, 1 ret i16 %e } ; Same as above with min/max reversed. define i16 @min_max_clamp_2(i16 %x) { ; CHECK-LABEL: @min_max_clamp_2( ; CHECK-NEXT: [[A:%.*]] = icmp slt i16 [[X:%.*]], 2047 ; CHECK-NEXT: [[B:%.*]] = select i1 [[A]], i16 [[X]], i16 2047 ; CHECK-NEXT: [[C:%.*]] = icmp sgt i16 [[B]], -2048 ; CHECK-NEXT: [[D:%.*]] = select i1 [[C]], i16 [[B]], i16 -2048 ; CHECK-NEXT: [[E:%.*]] = add nsw i16 [[D]], 1 ; CHECK-NEXT: ret i16 [[E]] ; %a = icmp slt i16 %x, 2047 %b = select i1 %a, i16 %x, i16 2047 %c = icmp sgt i16 %b, -2048 %d = select i1 %c, i16 %b, i16 -2048 %e = add i16 %d, 1 ret i16 %e } ; This contains a min/max pair to clamp a value to 12 bits. ; By analyzing the clamp pattern, we can tell that the second add doesn't ; overflow the original type and can be moved before the extend. define i32 @min_max_clamp_3(i16 %x) { ; CHECK-LABEL: @min_max_clamp_3( ; CHECK-NEXT: [[A:%.*]] = icmp sgt i16 [[X:%.*]], -2048 ; CHECK-NEXT: [[B:%.*]] = select i1 [[A]], i16 [[X]], i16 -2048 ; CHECK-NEXT: [[C:%.*]] = icmp slt i16 [[B]], 2047 ; CHECK-NEXT: [[D:%.*]] = select i1 [[C]], i16 [[B]], i16 2047 ; CHECK-NEXT: [[G:%.*]] = sext i16 [[D]] to i32 ; CHECK-NEXT: ret i32 [[G]] ; %a = icmp sgt i16 %x, -2048 %b = select i1 %a, i16 %x, i16 -2048 %c = icmp slt i16 %b, 2047 %d = select i1 %c, i16 %b, i16 2047 %e = add i16 %d, 1 %f = sext i16 %e to i32 %g = add i32 %f, -1 ret i32 %g } ; Same as above with min/max order reversed define i32 @min_max_clamp_4(i16 %x) { ; CHECK-LABEL: @min_max_clamp_4( ; CHECK-NEXT: [[A:%.*]] = icmp slt i16 [[X:%.*]], 2047 ; CHECK-NEXT: [[B:%.*]] = select i1 [[A]], i16 [[X]], i16 2047 ; CHECK-NEXT: [[C:%.*]] = icmp sgt i16 [[B]], -2048 ; CHECK-NEXT: [[D:%.*]] = select i1 [[C]], i16 [[B]], i16 -2048 ; CHECK-NEXT: [[G:%.*]] = sext i16 [[D]] to i32 ; CHECK-NEXT: ret i32 [[G]] ; %a = icmp slt i16 %x, 2047 %b = select i1 %a, i16 %x, i16 2047 %c = icmp sgt i16 %b, -2048 %d = select i1 %c, i16 %b, i16 -2048 %e = add i16 %d, 1 %f = sext i16 %e to i32 %g = add i32 %f, -1 ret i32 %g }