<table border="1" cellspacing="0" cellpadding="8">
    <tr>
        <th>Issue</th>
        <td>
            <a href=https://github.com/llvm/llvm-project/issues/139202>139202</a>
        </td>
    </tr>

    <tr>
        <th>Summary</th>
        <td>
            [SLPV] Pointer offsets truncated to 32-bits, resulting in wrong code
        </td>
    </tr>

    <tr>
      <th>Labels</th>
      <td>
            new issue
      </td>
    </tr>

    <tr>
      <th>Assignees</th>
      <td>
      </td>
    </tr>

    <tr>
      <th>Reporter</th>
      <td>
          rnk
      </td>
    </tr>
</table>

<pre>
    Consider:

```
$ cat t.ll
target datalayout = "e-m:e-p270:32:32-p271:32:32-p272:64:64-i64:64-i128:128-f80:128-n8:16:32:64-S128"
target triple = "x86_64-grtev4-linux-gnu"

define void @_ZN12_GLOBAL__N_111LargeObjectILm4294967296EEC2Em(ptr %this) #0 {
entry:
 store i64 1, ptr %this, align 8
  %b = getelementptr i8, ptr %this, i64 8
 store i64 2, ptr %b, align 8
  %c = getelementptr i8, ptr %this, i64 u0x100000010
  store i64 3, ptr %c, align 8
  %d = getelementptr i8, ptr %this, i64 u0x100000018
  store i64 4, ptr %d, align 8
  ret void
}

attributes #0 = { "target-features"="+aes,+avx,+cmov,+crc32,+cx16,+cx8,+fxsr,+mmx,+pclmul,+popcnt,+prfchw,+sse,+sse2,+sse3,+sse4.1,+sse4.2,+ssse3,+x87,+xsave" }

$ opt -passes=slp-vectorizer t.ll  -S -o -
; ModuleID = 't.ll'
source_filename = "t.ll"
target datalayout = "e-m:e-p270:32:32-p271:32:32-p272:64:64-i64:64-i128:128-f80:128-n8:16:32:64-S128"
target triple = "x86_64-grtev4-linux-gnu"

define void @_ZN12_GLOBAL__N_111LargeObjectILm4294967296EEC2Em(ptr %this) #0 {
entry:
 store <4 x i64> <i64 1, i64 2, i64 3, i64 4>, ptr %this, align 8
  ret void
}

attributes #0 = { "target-features"="+aes,+avx,+cmov,+crc32,+cx16,+cx8,+fxsr,+mmx,+pclmul,+popcnt,+prfchw,+sse,+sse2,+sse3,+sse4.1,+sse4.2,+ssse3,+x87,+xsave" }
```

Clearly, somewhere inside SLPV, the GEP offsets here are truncated from 64-bits to 32. To quickly check SLPV with static analysis, I did this:

```
$ ninja opt # build everything once
$ touch ../llvm/lib/Transforms/Vectorize/SLPVectorizer.cpp
$ CCC_OVERRIDE_OPTIONS='+-Wshorten-64-to-32' ninja opt | tee slpv-truncations.txt
...
```

Unfortunately, there are 733 hits:
```
$ grep warning: slpv-truncations.txt  | wc -l
     733
```

This is not a recent regression, it goes back to LLVM 14 and earlier: https://godbolt.org/z/9baE551T7 LLVM 14 is just as far back as the IR is parseable out of the box.

I think the next move here would be to do a global search & replace of getZExtValue with some variant that asserts when the result is wider than 32-bits, or to focus only on the warnings that include getZExtValue in the warning text snippet.
</pre>
<img width="1" height="1" alt="" src="http://email.email.llvm.org/o/eJzsVs1u4zgSfhr6UpAhUbJkHXxw_DMIkOk0urNZYC4GJZUldihSS5ZsZ55-QcpxJ929WMycJzCUj2L9qaq-IoVzstWIK7a4Y4vtTIzUGbuy-mVWmeZ1tTHayQYtS9csDr88vv7iNeMZ1IKA5kqxeE3CtkjQCBJKvJqRgKVbYJxj1LN0jdHAi5il65SHh18mH5ce5Vl4RPIGEr5k6Trhy-i4jK9Ih1f5m3qeRV-9GOff4yArB4VvMVyW-SHPotYSnrJIST1eolaPkwaL1w0epUY4GdkAy-LDH58Sfvjt4fFu_XA4fDokSfLgzT5W37Cm-4c-42VW5gUv891uw3c948uBLDC-oE46xktgPI2BFXcsXqMm-zqlEBwZiyDzDBLGN_BBaQNCyVbD0gv611UIv0VChT1q8tJy-Qs9b2_50Tx_J1b9wnb9V2yP8SWJw18SBwPf_aTvVOpf-Gn-pp_lD36ydyrNj34sUqidL2axnUoqiKysRkJ3rYXvhOLOd8PUItERBY0Wne-CdOuf_E745caD02UCdW9OV2TrlF_hJcnf0HICx4uzE-r7q-pQq35UV2yGWtMV22PdnSfsHN4Av6H0hrJ58g7fJG4il2VxBU6ckHEOtwx4gpqBIBqEc-hYunVqiE5Yk7HyT7SBuQDRV4gMRF4hvYPfTTMqvN9emVMEdvOCxWtnRlvj4SgVatHfqDUJ8H8mwF-aACzdZHCB8JE7v7qNhBt5b-ya2j_d_Z-B8Q8JfibB--MqXm8UCqtefeKc6fHcoR8u4YiDrw-fn_0GdQi_7T6DOR4dkoMgIywC2VHXgrCBozU95FlUSXJABlI-hycD_xll_aJeoe6wfgn24CypA0eCZA1CC_XqprLdQyMbCEX8XyerlvqbCPRlPIVqlKoBPKF9pU7qFoyu8SpJZqw7mM8Z3yt16v0_WTG-f7JCu6OxvWN8__zGesb3PrTbEJjXw3A1tNlsDo_Puy9f7re7w-Pnp_vHT19DTxSM30X_dp2xhDrKs4hM5JugeB9lsQFCBKeGU3TNlTTazelCLF7P5_Of6_EvfTSWRi0Ip6rQLdtFmkIn6S0_PySntTjAWVgtdcvS9S-dQgjpXEOkAj0AvNGfg3jqpAPpQBsCARZr1AQWW4vOSaMDAQlagw4qUb_4gj88PP8OSQZCN-A7SoYbEnREQwiY7xnft6apjKK5sS3j-z8Z35eV2C0WyVNxMyAdfBsdgXBwFHayL1zowfsvfncQ1qGoFIIfp-YYtipzmU-x3_se0i_hrcYLQW9OOLXs2YyqgQp9vI0BAa0ylVDgUNi6A8ZzsDgoUaM32yL9sbvQs1AjXrvW9AgnYaXQBNQJH6RDSw7OHerg0aIbFfkwz_6S6KU0pDzwwqfNWO_8aOrRgdHqFcykdy2cm8xKXauxwY8hyA-SQP7bnJbDgDSfNau0KdNSzHCVFFle5HxRLmbdKhUi46Wo45KXWbaoy2V2xKZqlmlaJrkoZnLFY76IF3EZp1m5WMyTpmyKvMR0ccx5WSDLYuyFVHNPJF-5mXRuxFWSljzmMyUqVC5cljnXeIaw62fmYjuzK68UVWPrWBYr6ch9N0OSVLhlhzGz2MJnIzWhvY2Z79MlDJRbDqcc-xxIDWdrdAu1aXA2WrX6od8kdWM1r03_bhD4iAZr_JnF-D6E66fB9XtOK_7fAAAA__8rqo-z">