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      1 ; RUN: opt < %s -basicaa -aa-eval -print-all-alias-modref-info -disable-output 2>&1 | FileCheck %s
      2 target datalayout = "e-m:e-p:32:32-i64:64-v128:64:128-a:0:32-n32-S64"
      3 target triple = "thumbv7--linux-gnueabi"
      4 
      5 ; CHECK-LABEL: test_zext_sext_amounts255
      6 ; CHECK: NoAlias: i8* %a, i8* %b
      7 define void @test_zext_sext_amounts255(i8* %mem) {
      8   %sext.1 = sext i8 255 to i16
      9   %sext.zext.1 = zext i16 %sext.1 to i64
     10   %sext.2 = sext i8 255 to i32
     11   %sext.zext.2 = zext i32 %sext.2 to i64
     12   %a = getelementptr inbounds i8, i8* %mem, i64 %sext.zext.1
     13   %b = getelementptr inbounds i8, i8* %mem, i64 %sext.zext.2
     14   ret void
     15 }
     16 
     17 ; CHECK-LABEL: test_zext_sext_amounts
     18 ; CHECK: PartialAlias: i8* %a, i8* %b
     19 ; %a and %b only PartialAlias as, although they're both zext(sext(%num)) they'll extend the sign by a different
     20 ; number of bits before zext-ing the remainder.
     21 define void @test_zext_sext_amounts(i8* %mem, i8 %num) {
     22   %sext.1 = sext i8 %num to i16
     23   %sext.zext.1 = zext i16 %sext.1 to i64
     24   %sext.2 = sext i8 %num to i32
     25   %sext.zext.2 = zext i32 %sext.2 to i64
     26   %a = getelementptr inbounds i8, i8* %mem, i64 %sext.zext.1
     27   %b = getelementptr inbounds i8, i8* %mem, i64 %sext.zext.2
     28   ret void
     29 }
     30 
     31 ; CHECK-LABEL: based_on_pr18068
     32 ; CHECK: NoAlias: i8* %a, i8* %b
     33 ; CHECK: NoAlias: i8* %a, i8* %c
     34 define void @based_on_pr18068(i32 %loaded, i8* %mem) {
     35   %loaded.64 = zext i32 %loaded to i64
     36   %add1 = add i32 %loaded, -1 ; unsigned wraps unless %loaded == 0
     37   %add1.64 = zext i32 %add1 to i64 ; is zext(%loaded) always != zext(%loaded - 1)? Yes -> NoAlias
     38   %sub1 = sub i32 %loaded, 1 ; unsigned wraps iff %loaded == 0
     39   %sub1.64 = zext i32 %sub1 to i64 ; is zext(%loaded) always != zext(%loaded - 1)? Yes -> NoAlias
     40   %a = getelementptr inbounds i8, i8* %mem, i64 %loaded.64
     41   %b = getelementptr inbounds i8, i8* %mem, i64 %add1.64
     42   %c = getelementptr inbounds i8, i8* %mem, i64 %sub1.64
     43   ret void
     44 }
     45 
     46 ; CHECK-LABEL: test_path_dependence
     47 ; CHECK: PartialAlias: i8* %a, i8* %b
     48 ; CHECK: MustAlias: i8* %a, i8* %c
     49 ; CHECK: PartialAlias: i8* %a, i8* %d
     50 define void @test_path_dependence(i32 %p, i8* %mem) {
     51   %p.minus1 = add i32 %p, -1 ; this will always unsigned-wrap, unless %p == 0
     52   %p.minus1.64 = zext i32 %p.minus1 to i64
     53   %p.64.again = add i64 %p.minus1.64, 1 ; either %p (if we wrapped) or 4294967296 (if we didn't)
     54 
     55   %p.nsw.nuw.minus1 = sub nsw nuw i32 %p, 1 ; as nuw we know %p >= 1, and as nsw %p <=   2147483647
     56   %p.nsw.nuw.minus1.64 = zext i32 %p.nsw.nuw.minus1 to i64
     57   %p.nsw.nuw.64.again = add nsw nuw i64 %p.nsw.nuw.minus1.64, 1 ; ...so always exactly %p
     58 
     59   %p.nsw.minus1 = sub nsw i32 %p, 1 ; only nsw, so can only guarantee %p != 0x10000000
     60   %p.nsw.minus1.64 = zext i32 %p.nsw.minus1 to i64 ; when %p > 0x10000000 (ie <= 0 as a signed number) then the zext will make this a huge positive number
     61   %p.nsw.64.again = add nsw i64 %p.nsw.minus1.64, 1 ; ...and so this is very much != %p
     62 
     63   %p.64 = zext i32 %p to i64
     64   %a = getelementptr inbounds i8, i8* %mem, i64 %p.64
     65   %b = getelementptr inbounds i8, i8* %mem, i64 %p.64.again
     66   %c = getelementptr inbounds i8, i8* %mem, i64 %p.nsw.nuw.64.again
     67   %d = getelementptr inbounds i8, i8* %mem, i64 %p.nsw.64.again
     68   ret void
     69 }
     70 
     71 ; CHECK-LABEL: test_zext_sext_255
     72 ; CHECK: NoAlias: i8* %a, i8* %b
     73 define void @test_zext_sext_255(i8* %mem) {
     74   %zext.255 = zext i8 255 to i16 ; 0x00FF
     75   %sext.255 = sext i8 255 to i16 ; 0xFFFF
     76   %zext.sext.255 = zext i16 %sext.255 to i32 ; 0x0000FFFF
     77   %sext.zext.255 = sext i16 %zext.255 to i32 ; 0x000000FF
     78   %zext.zext.sext.255 = zext i32 %zext.sext.255 to i64
     79   %zext.sext.zext.255 = zext i32 %sext.zext.255 to i64
     80   %a = getelementptr inbounds i8, i8* %mem, i64 %zext.zext.sext.255
     81   %b = getelementptr inbounds i8, i8* %mem, i64 %zext.sext.zext.255
     82   ret void
     83 }
     84 
     85 ; CHECK-LABEL: test_zext_sext_num
     86 ; CHECK: PartialAlias: i8* %a, i8* %b
     87 ; %a and %b NoAlias if %num == 255 (see @test_zext_sext_255), but %a and %b NoAlias for other values of %num (e.g. 0)
     88 define void @test_zext_sext_num(i8* %mem, i8 %num) {
     89   %zext.num = zext i8 %num to i16
     90   %sext.num = sext i8 %num to i16
     91   %zext.sext.num = zext i16 %sext.num to i32
     92   %sext.zext.num = sext i16 %zext.num to i32
     93   %zext.zext.sext.num = zext i32 %zext.sext.num to i64
     94   %zext.sext.zext.num = zext i32 %sext.zext.num to i64
     95   %a = getelementptr inbounds i8, i8* %mem, i64 %zext.zext.sext.num
     96   %b = getelementptr inbounds i8, i8* %mem, i64 %zext.sext.zext.num
     97   ret void
     98 }
     99 
    100 ; CHECK-LABEL: uncompressStream
    101 ; CHECK: MustAlias:  i8* %a, i8* %b
    102 ; CHECK: NoAlias:  i8* %a, i8* %c
    103 define void @uncompressStream(i8* %mem) {
    104   %zext.255 = zext i8 255 to i32
    105   %sext.255 = sext i8 255 to i32
    106   %a = getelementptr inbounds i8, i8* %mem, i32 255
    107   %b = getelementptr inbounds i8, i8* %mem, i32 %zext.255
    108   %c = getelementptr inbounds i8, i8* %mem, i32 %sext.255
    109   ret void
    110 }
    111 
    112 ; CHECK-LABEL: constantOffsetHeuristic_i3_i32
    113 ; CHECK: NoAlias:  i32* %a, i32* %b
    114 ; CHECK: NoAlias:  i32* %a, i32* %c
    115 ; CHECK: NoAlias:  i32* %b, i32* %c
    116 define void @constantOffsetHeuristic_i3_i32(i32* %mem, i3 %val) {
    117   %zext.plus.7 = add nsw i3 %val, 7
    118   %zext.plus.4 = add nsw i3 %val, 4
    119   %zext.val = zext i3 %val to i32
    120   %zext.4 = zext i3 %zext.plus.4 to i32
    121   %zext.7 = zext i3 %zext.plus.7 to i32
    122   %a = getelementptr inbounds i32, i32* %mem, i32 %zext.4
    123   %b = getelementptr inbounds i32, i32* %mem, i32 %zext.7
    124   %c = getelementptr inbounds i32, i32* %mem, i32 %zext.val
    125   ret void
    126 }
    127 
    128 ; CHECK-LABEL: constantOffsetHeuristic_i8_i32
    129 ; CHECK: NoAlias:  i32* %a, i32* %b
    130 ; CHECK: NoAlias:  i32* %a, i32* %c
    131 ; CHECK: NoAlias:  i32* %b, i32* %c
    132 define void @constantOffsetHeuristic_i8_i32(i32* %mem, i8 %val) {
    133   %zext.plus.7 = add nsw i8 %val, 7
    134   %zext.plus.4 = add nsw i8 %val, 4
    135   %zext.val = zext i8 %val to i32
    136   %zext.4 = zext i8 %zext.plus.4 to i32
    137   %zext.7 = zext i8 %zext.plus.7 to i32
    138   %a = getelementptr inbounds i32, i32* %mem, i32 %zext.4
    139   %b = getelementptr inbounds i32, i32* %mem, i32 %zext.7
    140   %c = getelementptr inbounds i32, i32* %mem, i32 %zext.val
    141   ret void
    142 }
    143 
    144 ; CHECK-LABEL: constantOffsetHeuristic_i3_i8
    145 ; CHECK: PartialAlias:  i32* %a, i32* %b
    146 ; CHECK: NoAlias:  i32* %a, i32* %c
    147 ; CHECK: PartialAlias:  i32* %b, i32* %c
    148 define void @constantOffsetHeuristic_i3_i8(i8* %mem, i3 %val) {
    149   %zext.plus.7 = add nsw i3 %val, 7
    150   %zext.plus.4 = add nsw i3 %val, 4
    151   %zext.val = zext i3 %val to i32
    152   %zext.4 = zext i3 %zext.plus.4 to i32
    153   %zext.7 = zext i3 %zext.plus.7 to i32
    154   %a.8 = getelementptr inbounds i8, i8* %mem, i32 %zext.4
    155   %b.8 = getelementptr inbounds i8, i8* %mem, i32 %zext.7
    156   %c.8 = getelementptr inbounds i8, i8* %mem, i32 %zext.val
    157   %a = bitcast i8* %a.8 to i32*
    158   %b = bitcast i8* %b.8 to i32*
    159   %c = bitcast i8* %c.8 to i32*
    160   ret void
    161 }
    162 
    163 ; CHECK-LABEL: constantOffsetHeuristic_i8_i8
    164 ; CHECK: PartialAlias:  i32* %a, i32* %b
    165 ; CHECK: NoAlias:  i32* %a, i32* %c
    166 ; CHECK: NoAlias:  i32* %b, i32* %c
    167 define void @constantOffsetHeuristic_i8_i8(i8* %mem, i8 %val) {
    168   %zext.plus.7 = add nsw i8 %val, 7
    169   %zext.plus.4 = add nsw i8 %val, 4
    170   %zext.val = zext i8 %val to i32
    171   %zext.4 = zext i8 %zext.plus.4 to i32
    172   %zext.7 = zext i8 %zext.plus.7 to i32
    173   %a.8 = getelementptr inbounds i8, i8* %mem, i32 %zext.4
    174   %b.8 = getelementptr inbounds i8, i8* %mem, i32 %zext.7
    175   %c.8 = getelementptr inbounds i8, i8* %mem, i32 %zext.val
    176   %a = bitcast i8* %a.8 to i32*
    177   %b = bitcast i8* %b.8 to i32*
    178   %c = bitcast i8* %c.8 to i32*
    179   ret void
    180 }
    181