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      1 ; This test case tests the InstructionCombining optimization that
      2 ; reduces things like:
      3 ;   %Y = sext i8 %X to i32 
      4 ;   %C = icmp ult i32 %Y, 1024
      5 ; to
      6 ;   %C = i1 true
      7 ; It includes test cases for different constant values, signedness of the
      8 ; cast operands, and types of setCC operators. In all cases, the cast should
      9 ; be eliminated. In many cases the setCC is also eliminated based on the
     10 ; constant value and the range of the casted value.
     11 ;
     12 ; RUN: opt < %s -instcombine -S | FileCheck %s
     13 ; END.
     14 define i1 @lt_signed_to_large_unsigned(i8 %SB) {
     15         %Y = sext i8 %SB to i32         ; <i32> [#uses=1]
     16         %C = icmp ult i32 %Y, 1024              ; <i1> [#uses=1]
     17         ret i1 %C
     18 ; CHECK: %C1 = icmp sgt i8 %SB, -1
     19 ; CHECK: ret i1 %C1
     20 }
     21 
     22 define i1 @lt_signed_to_large_signed(i8 %SB) {
     23         %Y = sext i8 %SB to i32         ; <i32> [#uses=1]
     24         %C = icmp slt i32 %Y, 1024              ; <i1> [#uses=1]
     25         ret i1 %C
     26 ; CHECK: ret i1 true
     27 }
     28 
     29 define i1 @lt_signed_to_large_negative(i8 %SB) {
     30         %Y = sext i8 %SB to i32         ; <i32> [#uses=1]
     31         %C = icmp slt i32 %Y, -1024             ; <i1> [#uses=1]
     32         ret i1 %C
     33 ; CHECK: ret i1 false
     34 }
     35 
     36 define i1 @lt_signed_to_small_unsigned(i8 %SB) {
     37         %Y = sext i8 %SB to i32
     38         %C = icmp ult i32 %Y, 17
     39         ret i1 %C
     40 ; CHECK: %C = icmp ult i8 %SB, 17
     41 ; CHECK: ret i1 %C
     42 }
     43 
     44 define i1 @lt_signed_to_small_signed(i8 %SB) {
     45         %Y = sext i8 %SB to i32         ; <i32> [#uses=1]
     46         %C = icmp slt i32 %Y, 17                ; <i1> [#uses=1]
     47         ret i1 %C
     48 ; CHECK: %C = icmp slt i8 %SB, 17
     49 ; CHECK: ret i1 %C
     50 }
     51 define i1 @lt_signed_to_small_negative(i8 %SB) {
     52         %Y = sext i8 %SB to i32         ; <i32> [#uses=1]
     53         %C = icmp slt i32 %Y, -17               ; <i1> [#uses=1]
     54         ret i1 %C
     55 ; CHECK: %C = icmp slt i8 %SB, -17
     56 ; CHECK: ret i1 %C
     57 }
     58 
     59 define i1 @lt_unsigned_to_large_unsigned(i8 %SB) {
     60         %Y = zext i8 %SB to i32         ; <i32> [#uses=1]
     61         %C = icmp ult i32 %Y, 1024              ; <i1> [#uses=1]
     62         ret i1 %C
     63 ; CHECK: ret i1 true
     64 }
     65 
     66 define i1 @lt_unsigned_to_large_signed(i8 %SB) {
     67         %Y = zext i8 %SB to i32         ; <i32> [#uses=1]
     68         %C = icmp slt i32 %Y, 1024              ; <i1> [#uses=1]
     69         ret i1 %C
     70 ; CHECK: ret i1 true
     71 }
     72 
     73 define i1 @lt_unsigned_to_large_negative(i8 %SB) {
     74         %Y = zext i8 %SB to i32         ; <i32> [#uses=1]
     75         %C = icmp slt i32 %Y, -1024             ; <i1> [#uses=1]
     76         ret i1 %C
     77 ; CHECK: ret i1 false
     78 }
     79 
     80 define i1 @lt_unsigned_to_small_unsigned(i8 %SB) {
     81         %Y = zext i8 %SB to i32         ; <i32> [#uses=1]
     82         %C = icmp ult i32 %Y, 17                ; <i1> [#uses=1]
     83         ret i1 %C
     84 ; CHECK: %C = icmp ult i8 %SB, 17
     85 ; CHECK: ret i1 %C
     86 }
     87 
     88 define i1 @lt_unsigned_to_small_signed(i8 %SB) {
     89         %Y = zext i8 %SB to i32
     90         %C = icmp slt i32 %Y, 17
     91         ret i1 %C
     92 ; CHECK: %C = icmp ult i8 %SB, 17
     93 ; CHECK: ret i1 %C
     94 }
     95 
     96 define i1 @lt_unsigned_to_small_negative(i8 %SB) {
     97         %Y = zext i8 %SB to i32         ; <i32> [#uses=1]
     98         %C = icmp slt i32 %Y, -17               ; <i1> [#uses=1]
     99         ret i1 %C
    100 ; CHECK: ret i1 false
    101 }
    102 
    103 define i1 @gt_signed_to_large_unsigned(i8 %SB) {
    104         %Y = sext i8 %SB to i32         ; <i32> [#uses=1]
    105         %C = icmp ugt i32 %Y, 1024              ; <i1> [#uses=1]
    106         ret i1 %C
    107 ; CHECK: %C = icmp slt i8 %SB, 0
    108 ; CHECK: ret i1 %C
    109 }
    110 
    111 define i1 @gt_signed_to_large_signed(i8 %SB) {
    112         %Y = sext i8 %SB to i32         ; <i32> [#uses=1]
    113         %C = icmp sgt i32 %Y, 1024              ; <i1> [#uses=1]
    114         ret i1 %C
    115 ; CHECK: ret i1 false
    116 }
    117 
    118 define i1 @gt_signed_to_large_negative(i8 %SB) {
    119         %Y = sext i8 %SB to i32         ; <i32> [#uses=1]
    120         %C = icmp sgt i32 %Y, -1024             ; <i1> [#uses=1]
    121         ret i1 %C
    122 ; CHECK: ret i1 true
    123 }
    124 
    125 define i1 @gt_signed_to_small_unsigned(i8 %SB) {
    126         %Y = sext i8 %SB to i32
    127         %C = icmp ugt i32 %Y, 17
    128         ret i1 %C
    129 ; CHECK: %C = icmp ugt i8 %SB, 17
    130 ; CHECK: ret i1 %C
    131 }
    132 
    133 define i1 @gt_signed_to_small_signed(i8 %SB) {
    134         %Y = sext i8 %SB to i32         ; <i32> [#uses=1]
    135         %C = icmp sgt i32 %Y, 17                ; <i1> [#uses=1]
    136         ret i1 %C
    137 ; CHECK: %C = icmp sgt i8 %SB, 17
    138 ; CHECK: ret i1 %C
    139 }
    140 
    141 define i1 @gt_signed_to_small_negative(i8 %SB) {
    142         %Y = sext i8 %SB to i32         ; <i32> [#uses=1]
    143         %C = icmp sgt i32 %Y, -17               ; <i1> [#uses=1]
    144         ret i1 %C
    145 ; CHECK: %C = icmp sgt i8 %SB, -17
    146 ; CHECK: ret i1 %C
    147 }
    148 
    149 define i1 @gt_unsigned_to_large_unsigned(i8 %SB) {
    150         %Y = zext i8 %SB to i32         ; <i32> [#uses=1]
    151         %C = icmp ugt i32 %Y, 1024              ; <i1> [#uses=1]
    152         ret i1 %C
    153 ; CHECK: ret i1 false
    154 }
    155 
    156 define i1 @gt_unsigned_to_large_signed(i8 %SB) {
    157         %Y = zext i8 %SB to i32         ; <i32> [#uses=1]
    158         %C = icmp sgt i32 %Y, 1024              ; <i1> [#uses=1]
    159         ret i1 %C
    160 ; CHECK: ret i1 false
    161 }
    162 
    163 define i1 @gt_unsigned_to_large_negative(i8 %SB) {
    164         %Y = zext i8 %SB to i32         ; <i32> [#uses=1]
    165         %C = icmp sgt i32 %Y, -1024             ; <i1> [#uses=1]
    166         ret i1 %C
    167 ; CHECK: ret i1 true
    168 }
    169 
    170 define i1 @gt_unsigned_to_small_unsigned(i8 %SB) {
    171         %Y = zext i8 %SB to i32         ; <i32> [#uses=1]
    172         %C = icmp ugt i32 %Y, 17                ; <i1> [#uses=1]
    173         ret i1 %C
    174 ; CHECK: %C = icmp ugt i8 %SB, 17
    175 ; CHECK: ret i1 %C
    176 }
    177 
    178 define i1 @gt_unsigned_to_small_signed(i8 %SB) {
    179         %Y = zext i8 %SB to i32
    180         %C = icmp sgt i32 %Y, 17
    181         ret i1 %C
    182 ; CHECK: %C = icmp ugt i8 %SB, 17
    183 ; CHECK: ret i1 %C
    184 }
    185 
    186 define i1 @gt_unsigned_to_small_negative(i8 %SB) {
    187         %Y = zext i8 %SB to i32         ; <i32> [#uses=1]
    188         %C = icmp sgt i32 %Y, -17               ; <i1> [#uses=1]
    189         ret i1 %C
    190 ; CHECK: ret i1 true
    191 }
    192 
    193