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      1 ; This test makes sure that add instructions are properly eliminated.
      2 
      3 ; RUN: opt < %s -instcombine -S | \
      4 ; RUN:    grep -v OK | not grep add
      5 
      6 define i32 @test1(i32 %A) {
      7         %B = add i32 %A, 0              ; <i32> [#uses=1]
      8         ret i32 %B
      9 }
     10 
     11 define i32 @test2(i32 %A) {
     12         %B = add i32 %A, 5              ; <i32> [#uses=1]
     13         %C = add i32 %B, -5             ; <i32> [#uses=1]
     14         ret i32 %C
     15 }
     16 
     17 define i32 @test3(i32 %A) {
     18         %B = add i32 %A, 5              ; <i32> [#uses=1]
     19         ;; This should get converted to an add
     20         %C = sub i32 %B, 5              ; <i32> [#uses=1]
     21         ret i32 %C
     22 }
     23 
     24 define i32 @test4(i32 %A, i32 %B) {
     25         %C = sub i32 0, %A              ; <i32> [#uses=1]
     26         ; D = B + -A = B - A
     27         %D = add i32 %B, %C             ; <i32> [#uses=1]
     28         ret i32 %D
     29 }
     30 
     31 define i32 @test5(i32 %A, i32 %B) {
     32         %C = sub i32 0, %A              ; <i32> [#uses=1]
     33         ; D = -A + B = B - A
     34         %D = add i32 %C, %B             ; <i32> [#uses=1]
     35         ret i32 %D
     36 }
     37 
     38 define i32 @test6(i32 %A) {
     39         %B = mul i32 7, %A              ; <i32> [#uses=1]
     40         ; C = 7*A+A == 8*A == A << 3
     41         %C = add i32 %B, %A             ; <i32> [#uses=1]
     42         ret i32 %C
     43 }
     44 
     45 define i32 @test7(i32 %A) {
     46         %B = mul i32 7, %A              ; <i32> [#uses=1]
     47         ; C = A+7*A == 8*A == A << 3
     48         %C = add i32 %A, %B             ; <i32> [#uses=1]
     49         ret i32 %C
     50 }
     51 
     52 ; (A & C1)+(B & C2) -> (A & C1)|(B & C2) iff C1&C2 == 0
     53 define i32 @test8(i32 %A, i32 %B) {
     54         %A1 = and i32 %A, 7             ; <i32> [#uses=1]
     55         %B1 = and i32 %B, 128           ; <i32> [#uses=1]
     56         %C = add i32 %A1, %B1           ; <i32> [#uses=1]
     57         ret i32 %C
     58 }
     59 
     60 define i32 @test9(i32 %A) {
     61         %B = shl i32 %A, 4              ; <i32> [#uses=2]
     62         ; === shl int %A, 5
     63         %C = add i32 %B, %B             ; <i32> [#uses=1]
     64         ret i32 %C
     65 }
     66 
     67 define i1 @test10(i8 %A, i8 %b) {
     68         %B = add i8 %A, %b              ; <i8> [#uses=1]
     69         ; === A != -b
     70         %c = icmp ne i8 %B, 0           ; <i1> [#uses=1]
     71         ret i1 %c
     72 }
     73 
     74 define i1 @test11(i8 %A) {
     75         %B = add i8 %A, -1              ; <i8> [#uses=1]
     76         ; === A != 1
     77         %c = icmp ne i8 %B, 0           ; <i1> [#uses=1]
     78         ret i1 %c
     79 }
     80 
     81 define i32 @test12(i32 %A, i32 %B) {
     82         ; Should be transformed into shl A, 1
     83          %C_OK = add i32 %B, %A          ; <i32> [#uses=1]
     84         br label %X
     85 
     86 X:              ; preds = %0
     87         %D = add i32 %C_OK, %A          ; <i32> [#uses=1]
     88         ret i32 %D
     89 }
     90 
     91 define i32 @test13(i32 %A, i32 %B, i32 %C) {
     92         %D_OK = add i32 %A, %B          ; <i32> [#uses=1]
     93         %E_OK = add i32 %D_OK, %C               ; <i32> [#uses=1]
     94         ;; shl A, 1
     95         %F = add i32 %E_OK, %A          ; <i32> [#uses=1]
     96         ret i32 %F
     97 }
     98 
     99 define i32 @test14(i32 %offset, i32 %difference) {
    100         %tmp.2 = and i32 %difference, 3         ; <i32> [#uses=1]
    101         %tmp.3_OK = add i32 %tmp.2, %offset             ; <i32> [#uses=1]
    102         %tmp.5.mask = and i32 %difference, -4           ; <i32> [#uses=1]
    103         ; == add %offset, %difference
    104         %tmp.8 = add i32 %tmp.3_OK, %tmp.5.mask         ; <i32> [#uses=1]
    105         ret i32 %tmp.8
    106 }
    107 
    108 define i8 @test15(i8 %A) {
    109         ; Does not effect result
    110         %B = add i8 %A, -64             ; <i8> [#uses=1]
    111         ; Only one bit set
    112         %C = and i8 %B, 16              ; <i8> [#uses=1]
    113         ret i8 %C
    114 }
    115 
    116 define i8 @test16(i8 %A) {
    117         ; Turn this into a XOR
    118         %B = add i8 %A, 16              ; <i8> [#uses=1]
    119         ; Only one bit set
    120         %C = and i8 %B, 16              ; <i8> [#uses=1]
    121         ret i8 %C
    122 }
    123 
    124 define i32 @test17(i32 %A) {
    125         %B = xor i32 %A, -1             ; <i32> [#uses=1]
    126         ; == sub int 0, %A
    127         %C = add i32 %B, 1              ; <i32> [#uses=1]
    128         ret i32 %C
    129 }
    130 
    131 define i8 @test18(i8 %A) {
    132         %B = xor i8 %A, -1              ; <i8> [#uses=1]
    133         ; == sub ubyte 16, %A
    134         %C = add i8 %B, 17              ; <i8> [#uses=1]
    135         ret i8 %C
    136 }
    137 
    138 define i32 @test19(i1 %C) {
    139         %A = select i1 %C, i32 1000, i32 10             ; <i32> [#uses=1]
    140         %V = add i32 %A, 123            ; <i32> [#uses=1]
    141         ret i32 %V
    142 }
    143 
    144 define i32 @test20(i32 %x) {
    145         %tmp.2 = xor i32 %x, -2147483648                ; <i32> [#uses=1]
    146         ;; Add of sign bit -> xor of sign bit.
    147         %tmp.4 = add i32 %tmp.2, -2147483648            ; <i32> [#uses=1]
    148         ret i32 %tmp.4
    149 }
    150 
    151 define i1 @test21(i32 %x) {
    152         %t = add i32 %x, 4              ; <i32> [#uses=1]
    153         %y = icmp eq i32 %t, 123                ; <i1> [#uses=1]
    154         ret i1 %y
    155 }
    156 
    157 define i32 @test22(i32 %V) {
    158         %V2 = add i32 %V, 10            ; <i32> [#uses=1]
    159         switch i32 %V2, label %Default [
    160                  i32 20, label %Lab1
    161                  i32 30, label %Lab2
    162         ]
    163 
    164 Default:                ; preds = %0
    165         ret i32 123
    166 
    167 Lab1:           ; preds = %0
    168         ret i32 12312
    169 
    170 Lab2:           ; preds = %0
    171         ret i32 1231231
    172 }
    173 
    174 define i32 @test23(i1 %C, i32 %a) {
    175 entry:
    176         br i1 %C, label %endif, label %else
    177 
    178 else:           ; preds = %entry
    179         br label %endif
    180 
    181 endif:          ; preds = %else, %entry
    182         %b.0 = phi i32 [ 0, %entry ], [ 1, %else ]              ; <i32> [#uses=1]
    183         %tmp.4 = add i32 %b.0, 1                ; <i32> [#uses=1]
    184         ret i32 %tmp.4
    185 }
    186 
    187 define i32 @test24(i32 %A) {
    188         %B = add i32 %A, 1              ; <i32> [#uses=1]
    189         %C = shl i32 %B, 1              ; <i32> [#uses=1]
    190         %D = sub i32 %C, 2              ; <i32> [#uses=1]
    191         ret i32 %D
    192 }
    193 
    194 define i64 @test25(i64 %Y) {
    195         %tmp.4 = shl i64 %Y, 2          ; <i64> [#uses=1]
    196         %tmp.12 = shl i64 %Y, 2         ; <i64> [#uses=1]
    197         %tmp.8 = add i64 %tmp.4, %tmp.12                ; <i64> [#uses=1]
    198         ret i64 %tmp.8
    199 }
    200 
    201 define i32 @test26(i32 %A, i32 %B) {
    202         %C = add i32 %A, %B             ; <i32> [#uses=1]
    203         %D = sub i32 %C, %B             ; <i32> [#uses=1]
    204         ret i32 %D
    205 }
    206 
    207 define i32 @test27(i1 %C, i32 %X, i32 %Y) {
    208         %A = add i32 %X, %Y             ; <i32> [#uses=1]
    209         %B = add i32 %Y, 123            ; <i32> [#uses=1]
    210         ;; Fold add through select.
    211         %C.upgrd.1 = select i1 %C, i32 %A, i32 %B               ; <i32> [#uses=1]
    212         %D = sub i32 %C.upgrd.1, %Y             ; <i32> [#uses=1]
    213         ret i32 %D
    214 }
    215 
    216 define i32 @test28(i32 %X) {
    217         %Y = add i32 %X, 1234           ; <i32> [#uses=1]
    218         %Z = sub i32 42, %Y             ; <i32> [#uses=1]
    219         ret i32 %Z
    220 }
    221 
    222 define i32 @test29(i32 %X, i32 %x) {
    223         %tmp.2 = sub i32 %X, %x         ; <i32> [#uses=2]
    224         %tmp.2.mask = and i32 %tmp.2, 63                ; <i32> [#uses=1]
    225         %tmp.6 = add i32 %tmp.2.mask, %x                ; <i32> [#uses=1]
    226         %tmp.7 = and i32 %tmp.6, 63             ; <i32> [#uses=1]
    227         %tmp.9 = and i32 %tmp.2, -64            ; <i32> [#uses=1]
    228         %tmp.10 = or i32 %tmp.7, %tmp.9         ; <i32> [#uses=1]
    229         ret i32 %tmp.10
    230 }
    231 
    232 define i64 @test30(i64 %x) {
    233         %tmp.2 = xor i64 %x, -9223372036854775808               ; <i64> [#uses=1]
    234         ;; Add of sign bit -> xor of sign bit.
    235         %tmp.4 = add i64 %tmp.2, -9223372036854775808           ; <i64> [#uses=1]
    236         ret i64 %tmp.4
    237 }
    238 
    239 define i32 @test31(i32 %A) {
    240         %B = add i32 %A, 4              ; <i32> [#uses=1]
    241         %C = mul i32 %B, 5              ; <i32> [#uses=1]
    242         %D = sub i32 %C, 20             ; <i32> [#uses=1]
    243         ret i32 %D
    244 }
    245 
    246 define i32 @test32(i32 %A) {
    247         %B = add i32 %A, 4              ; <i32> [#uses=1]
    248         %C = shl i32 %B, 2              ; <i32> [#uses=1]
    249         %D = sub i32 %C, 16             ; <i32> [#uses=1]
    250         ret i32 %D
    251 }
    252 
    253 define i8 @test33(i8 %A) {
    254         %B = and i8 %A, -2              ; <i8> [#uses=1]
    255         %C = add i8 %B, 1               ; <i8> [#uses=1]
    256         ret i8 %C
    257 }
    258 
    259 define i8 @test34(i8 %A) {
    260         %B = add i8 %A, 64              ; <i8> [#uses=1]
    261         %C = and i8 %B, 12              ; <i8> [#uses=1]
    262         ret i8 %C
    263 }
    264 
    265 define i32 @test35(i32 %a) {
    266         %tmpnot = xor i32 %a, -1                ; <i32> [#uses=1]
    267         %tmp2 = add i32 %tmpnot, %a             ; <i32> [#uses=1]
    268         ret i32 %tmp2
    269 }
    270 
    271 define i32 @test36(i32 %a) {
    272 	%x = and i32 %a, -2
    273 	%y = and i32 %a, -126
    274 	%z = add i32 %x, %y
    275 	%q = and i32 %z, 1  ; always zero
    276 	ret i32 %q
    277 }
    278 
    279 define i1 @test37(i32 %a, i32 %b) nounwind readnone {
    280   %add = add i32 %a, %b
    281   %cmp = icmp eq i32 %add, %a
    282   ret i1 %cmp
    283 }
    284 
    285 define i1 @test38(i32 %a, i32 %b) nounwind readnone {
    286   %add = add i32 %a, %b
    287   %cmp = icmp eq i32 %add, %b
    288   ret i1 %cmp
    289 }
    290 
    291 define i1 @test39(i32 %a, i32 %b) nounwind readnone {
    292   %add = add i32 %b, %a
    293   %cmp = icmp eq i32 %add, %a
    294   ret i1 %cmp
    295 }
    296 
    297 define i1 @test40(i32 %a, i32 %b) nounwind readnone {
    298   %add = add i32 %b, %a
    299   %cmp = icmp eq i32 %add, %b
    300   ret i1 %cmp
    301 }
    302