<table border="1" cellspacing="0" cellpadding="8">
<tr>
<th>Issue</th>
<td>
<a href=https://github.com/llvm/llvm-project/issues/122583>122583</a>
</td>
</tr>
<tr>
<th>Summary</th>
<td>
[SLPVectorizer] Miscompilation
</td>
</tr>
<tr>
<th>Labels</th>
<td>
miscompilation,
llvm:SLPVectorizer,
generated by fuzzer
</td>
</tr>
<tr>
<th>Assignees</th>
<td>
</td>
</tr>
<tr>
<th>Reporter</th>
<td>
dtcxzyw
</td>
</tr>
</table>
<pre>
Reproducer: https://godbolt.org/z/7eEEeeKoo
Sorry, I cannot provide alive2 link since `llvm.vector.insert.v8i64.v4i64` is not supported.
```
; bin/opt -passes=slp-vectorizer reduced.ll -S -o opt.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-unknown-linux-gnu"
@j = global [4 x i64] zeroinitializer
define i32 @main() {
entry:
%.pre.i = load i64, ptr getelementptr inbounds nuw (i8, ptr @j, i64 24), align 8
%.pre50.i = load i64, ptr getelementptr inbounds nuw (i8, ptr @j, i64 16), align 16
%.pre51.i = load i64, ptr getelementptr inbounds nuw (i8, ptr @j, i64 8), align 8
%.pre52.i = load i64, ptr @j, align 16
%0 = or i64 %.pre51.i, 0
%1 = trunc i64 %.pre.i to i32
%2 = add i32 %1, 0
%3 = trunc i64 %.pre50.i to i32
%4 = add i32 %3, 0
%5 = trunc i64 %.pre51.i to i32
%6 = add i32 %5, 0
%7 = trunc i64 0 to i32
%8 = add i32 %5, 0
%9 = add i32 %7, 0
%10 = add i32 %1, 0
%11 = add i32 %3, 0
%12 = add i32 %5, 0
%13 = add i32 %7, 0
%14 = trunc i64 %.pre.i to i32
%15 = add i32 %14, 0
%16 = trunc i64 %.pre50.i to i32
%17 = add i32 %16, 0
%18 = trunc i64 %.pre51.i to i32
%19 = add i32 %18, 0
%20 = trunc i64 %.pre52.i to i32
%conv14.1.i = or i32 %9, %13
%21 = or i32 %conv14.1.i, %6
%22 = or i32 %21, %8
%23 = or i32 %22, %12
%24 = or i32 %23, %4
%25 = or i32 %24, %11
%26 = or i32 %25, %2
%27 = or i32 %26, %10
%28 = or i32 %27, %15
%29 = or i32 %28, %17
%30 = or i32 %29, %19
%31 = add i32 %14, 0
%32 = add i32 %16, 0
%33 = add i32 %18, 0
%34 = add i32 %20, 0
%35 = add i32 %14, 0
%36 = add i32 %16, 0
%37 = add i32 %18, 0
%38 = add i32 %20, 0
%39 = add i32 %14, 0
%40 = add i32 %16, 0
%41 = add i32 %18, 0
%42 = add i32 %20, 0
%inc.3.3.i.1 = or i64 %.pre52.i, 0
%conv14.i.1 = or i32 %38, %34
%conv14.1.i.1 = or i32 %conv14.i.1, %42
%conv14.3.i.1 = or i32 %conv14.1.i.1, %33
%conv14.145.i.1 = or i32 %conv14.3.i.1, %37
%conv14.1.1.i.1 = or i32 %conv14.145.i.1, %41
%conv14.3.1.i.1 = or i32 %conv14.1.1.i.1, %32
%conv14.247.i.1 = or i32 %conv14.3.1.i.1, %36
%conv14.1.2.i.1 = or i32 %conv14.247.i.1, %40
%conv14.3.2.i.1 = or i32 %conv14.1.2.i.1, %31
%conv14.349.i.1 = or i32 %conv14.3.2.i.1, %35
%conv14.1.3.i.1 = or i32 %conv14.349.i.1, %39
%conv14.3.3.i.1 = or i32 %conv14.1.3.i.1, %30
ret i32 %conv14.3.3.i.1
}
```
Output:
```
source_filename = "/app/example.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-unknown-linux-gnu"
define i32 @main() {
%0 = load <4 x i64>, ptr @j, align 16
%1 = or i64 poison, 0
%2 = shufflevector <4 x i64> %0, <4 x i64> poison, <8 x i32> <i32 poison, i32 poison, i32 poison, i32 poison, i32 poison, i32 1, i32 poison, i32 poison>
%3 = shufflevector <4 x i64> %0, <4 x i64> poison, <8 x i32> <i32 0, i32 1, i32 2, i32 3, i32 poison, i32 poison, i32 poison, i32 poison>
%4 = shufflevector <8 x i64> %3, <8 x i64> <i64 poison, i64 poison, i64 poison, i64 poison, i64 0, i64 poison, i64 poison, i64 poison>, <8 x i32> <i32 poison, i32 poison, i32 poison, i32 poison, i32 12, i32 1, i32 poison, i32 poison>
%5 = call <8 x i64> @llvm.vector.insert.v8i64.v4i64(<8 x i64> %4, <4 x i64> %0, i64 0)
%6 = trunc <8 x i64> %5 to <8 x i32>
%7 = shufflevector <8 x i32> %6, <8 x i32> poison, <16 x i32> <i32 0, i32 0, i32 0, i32 1, i32 1, i32 1, i32 2, i32 2, i32 2, i32 3, i32 3, i32 3, i32 4, i32 4, i32 5, i32 5>
%8 = add <16 x i32> %7, zeroinitializer
%9 = extractelement <4 x i64> %0, i32 0
%inc.3.3.i.1 = or i64 %9, 0
%10 = call i32 @llvm.vector.reduce.or.v16i32(<16 x i32> %8)
%11 = call i32 @llvm.vector.reduce.or.v8i32(<8 x i32> poison)
%op.rdx = or i32 %10, %11
ret i32 %op.rdx
}
declare <8 x i64> @llvm.vector.insert.v8i64.v4i64(<8 x i64>, <4 x i64>, i64 immarg) #0
declare i32 @llvm.vector.reduce.or.v16i32(<16 x i32>) #0
declare i32 @llvm.vector.reduce.or.v8i32(<8 x i32>) #0
attributes #0 = { nocallback nofree nosync nounwind speculatable willreturn memory(none) }
```
lli output:
```
> bin/lli reduced.ll
> echo $?
0
> bin/lli opt.ll
> echo $?
255
```
[llubi](https://github.com/dtcxzyw/llvm-ub-aware-interpreter) output:
Before:
```
> ./llubi reduced.ll --verbose
Entering function main
%0 = getelementptr inbounds nuw i8, ptr @j, i64 24 -> Ptr 40[@j + 24]
%.pre.i = load i64, ptr %0, align 8 -> i64 0
%1 = getelementptr inbounds nuw i8, ptr @j, i64 16 -> Ptr 32[@j + 16]
%.pre50.i = load i64, ptr %1, align 16 -> i64 0
%2 = getelementptr inbounds nuw i8, ptr @j, i64 8 -> Ptr 24[@j + 8]
%.pre51.i = load i64, ptr %2, align 8 -> i64 0
%.pre52.i = load i64, ptr @j, align 16 -> i64 0
%3 = or i64 %.pre51.i, 0 -> i64 0
%4 = trunc i64 %.pre.i to i32 -> i32 0
%5 = add i32 %4, 0 -> i32 0
%6 = trunc i64 %.pre50.i to i32 -> i32 0
%7 = add i32 %6, 0 -> i32 0
%8 = trunc i64 %.pre51.i to i32 -> i32 0
%9 = add i32 %8, 0 -> i32 0
%10 = trunc i64 0 to i32 -> i32 0
%11 = add i32 %8, 0 -> i32 0
%12 = add i32 %10, 0 -> i32 0
%13 = add i32 %4, 0 -> i32 0
%14 = add i32 %6, 0 -> i32 0
%15 = add i32 %8, 0 -> i32 0
%16 = add i32 %10, 0 -> i32 0
%17 = trunc i64 %.pre.i to i32 -> i32 0
%18 = add i32 %17, 0 -> i32 0
%19 = trunc i64 %.pre50.i to i32 -> i32 0
%20 = add i32 %19, 0 -> i32 0
%21 = trunc i64 %.pre51.i to i32 -> i32 0
%22 = add i32 %21, 0 -> i32 0
%23 = trunc i64 %.pre52.i to i32 -> i32 0
%conv14.1.i = or i32 %12, %16 -> i32 0
%24 = or i32 %conv14.1.i, %9 -> i32 0
%25 = or i32 %24, %11 -> i32 0
%26 = or i32 %25, %15 -> i32 0
%27 = or i32 %26, %7 -> i32 0
%28 = or i32 %27, %14 -> i32 0
%29 = or i32 %28, %5 -> i32 0
%30 = or i32 %29, %13 -> i32 0
%31 = or i32 %30, %18 -> i32 0
%32 = or i32 %31, %20 -> i32 0
%33 = or i32 %32, %22 -> i32 0
%34 = add i32 %17, 0 -> i32 0
%35 = add i32 %19, 0 -> i32 0
%36 = add i32 %21, 0 -> i32 0
%37 = add i32 %23, 0 -> i32 0
%38 = add i32 %17, 0 -> i32 0
%39 = add i32 %19, 0 -> i32 0
%40 = add i32 %21, 0 -> i32 0
%41 = add i32 %23, 0 -> i32 0
%42 = add i32 %17, 0 -> i32 0
%43 = add i32 %19, 0 -> i32 0
%44 = add i32 %21, 0 -> i32 0
%45 = add i32 %23, 0 -> i32 0
%inc.3.3.i.1 = or i64 %.pre52.i, 0 -> i64 0
%conv14.i.1 = or i32 %41, %37 -> i32 0
%conv14.1.i.1 = or i32 %conv14.i.1, %45 -> i32 0
%conv14.3.i.1 = or i32 %conv14.1.i.1, %36 -> i32 0
%conv14.145.i.1 = or i32 %conv14.3.i.1, %40 -> i32 0
%conv14.1.1.i.1 = or i32 %conv14.145.i.1, %44 -> i32 0
%conv14.3.1.i.1 = or i32 %conv14.1.1.i.1, %35 -> i32 0
%conv14.247.i.1 = or i32 %conv14.3.1.i.1, %39 -> i32 0
%conv14.1.2.i.1 = or i32 %conv14.247.i.1, %43 -> i32 0
%conv14.3.2.i.1 = or i32 %conv14.1.2.i.1, %34 -> i32 0
%conv14.349.i.1 = or i32 %conv14.3.2.i.1, %38 -> i32 0
%conv14.1.3.i.1 = or i32 %conv14.349.i.1, %42 -> i32 0
%conv14.3.3.i.1 = or i32 %conv14.1.3.i.1, %33 -> i32 0
ret i32 %conv14.3.3.i.1
Exiting function main
```
After:
```
> ./llubi opt.ll --verbose
Entering function main
%0 = load <4 x i64>, ptr @j, align 16 -> { i64 0, i64 0, i64 0, i64 0 }
%1 = or i64 poison, 1 -> poison
%2 = or i64 poison, 0 -> poison
%3 = shufflevector <4 x i64> %0, <4 x i64> poison, <8 x i32> <i32 poison, i32 poison, i32 poison, i32 poison, i32 poison, i32 1, i32 poison, i32 poison> -> { poison, poison, poison, poison, poison, i64 0, poison, poison }
%4 = shufflevector <4 x i64> %0, <4 x i64> poison, <8 x i32> <i32 0, i32 1, i32 2, i32 3, i32 poison, i32 poison, i32 poison, i32 poison> -> { i64 0, i64 0, i64 0, i64 0, poison, poison, poison, poison }
%5 = shufflevector <8 x i64> %4, <8 x i64> <i64 poison, i64 poison, i64 poison, i64 poison, i64 0, i64 poison, i64 poison, i64 poison>, <8 x i32> <i32 poison, i32 poison, i32 poison, i32 poison, i32 12, i32 1, i32 poison, i32 poison> -> { poison, poison, poison, poison, i64 0, i64 0, poison, poison }
%6 = call <8 x i64> @llvm.vector.insert.v8i64.v4i64(<8 x i64> %5, <4 x i64> %0, i64 0) -> { i64 0, i64 0, i64 0, i64 0, i64 0, i64 0, poison, poison }
%7 = trunc <8 x i64> %6 to <8 x i32> -> { i32 0, i32 0, i32 0, i32 0, i32 0, i32 0, poison, poison }
%8 = shufflevector <8 x i32> %7, <8 x i32> poison, <16 x i32> <i32 0, i32 0, i32 0, i32 1, i32 1, i32 1, i32 2, i32 2, i32 2, i32 3, i32 3, i32 3, i32 4, i32 4, i32 5, i32 5> -> { i32 0, i32 0, i32 0, i32 0, i32 0, i32 0, i32 0, i32 0, i32 0, i32 0, i32 0, i32 0, i32 0, i32 0, i32 0, i32 0 }
%9 = add <16 x i32> %8, zeroinitializer -> { i32 0, i32 0, i32 0, i32 0, i32 0, i32 0, i32 0, i32 0, i32 0, i32 0, i32 0, i32 0, i32 0, i32 0, i32 0, i32 0 }
%10 = extractelement <4 x i64> %0, i32 0 -> i64 0
%inc.3.3.i.1 = or i64 %10, 0 -> i64 0
%11 = call i32 @llvm.vector.reduce.or.v16i32(<16 x i32> %9) -> i32 0
%12 = call i32 @llvm.vector.reduce.or.v8i32(<8 x i32> poison) -> poison
%op.rdx = or i32 %11, %12 -> poison
ret i32 %op.rdx
Exiting function main
UB triggered: Return a poison value
Exited with immediate UB.
Stacktrace:
```
</pre>
<img width="1" height="1" alt="" src="http://email.email.llvm.org/o/eJzkWl1v5CjW_jXkBpVlwF91kYtKJ5Fevbva0bRmb0cum6ow7TIWxpWkf_0Kf5TNl1OV7lnNaFutCNuHh4fDAQ4PlbctO9aU3oP4AcSPd3knX7i4L2Xx9v399W7Py_f7X2kjeNkVVACygy9SNi0gO4CfAX4-8nLPKxlwcQT4-TvAzyl9eqL0_zkH4e4rF-Id4C_w_2CR1zWXsBH8zEoK84qdKYYVq7_BltUFhSAJq-p8Cs60kFwErG6pkME5Y0kUnCOWRCAJIWuhQmm7puFC0jIA4Q4k4fg_3AHyAPesBviZNxJumrxtaQvIY1s1mwGYfacCCqq6UwZVBTdf4YZD3sigqhRAuJO5OFIJy1zmVf7OOwkBeYQAY7o5AbKjmwanISA7gvs_6hHpj6qURP2fDbsUEM4A2SGcbQ5ZOJbq_lUyVU-izVdlhvHMQwrWVHTi8JYlvyfRpqu_1fy13lSs7t42x7obqqj_UfhHb3ys-D6vIIgfIvgGFY34EX6ngrOaSZZXyhFDlZIeWE0hIxiCKDzlyn8ZwFsI0gcQ7mgtxbsa8HAHIcBx0AgasL6NiudlD42_wEYKeKSSVvREa6meWL3nXV22sO5eIcAZyyY7RVKVWRJBHAG8VQ95xY41zJbNxOFPbAglWkMoUS1NDaGf2FC20iHsaWeqv-SmKoW9NRc98IKssg0nI9QbSdHVxdIuYFByNayTHe7t8rIcxhrHSIMhbph-EHSgyAQiGlDsAUIaEMBxYuLEGk5q4IQGjWy9-tb8nOpeC9fdgdB6L5HlTr15RD5oP7py2FBsEY10pOTqkUOphZXoWNlVg9ebWg5GmYaFQw8WtrAKXp9RFEzTUAX8ANnPpN6bF1RkmMx1R9vL7MHYMMVoNLnMSkxMEzy1OM-byLQho000BjKOTYtoQkEXlMS0iUebuaHUNEkmmHBqKTNN0skkvsBsTZtsskkvkz00bS6e3o5NEWsCGHFH7AVFDyZiTQEjQoi1kuBQN_go9om1hpgc7Ig3OFjLiMnBjnOdQ2SvJDqHyPakziGyPGlwYHURkIAELECuHQEbO8I4JZbW4xI2RQKJ7KlnWc8wU7ybE5b4a6FFPULGmJq-RbG_IllWTC2aK0RH2Iksssiu1dUJY50wjtI1wlrVxKKM_XVH4ImyOYJkre4IPLWLdMok2q5R1qrGFuWVgR2Bp7pbi_JqUGijO3RXUGnRG8zCHUgfjRz_X51sOjkkpMv3Le9EQX8_sIrW-emSMQP8nDcNwM_0LT81FVV5_jK__pvm-R8k7YvksU81AfkyHQPI00dJp7bENJy1vNb39f57-9IdDhUdjlV6A33j_Rhrb2coQL5k6r3yxpN6Uv2YP__IE1o1Ik96tvvTOxFaPPBUIJ_u2sw6crPONNZkyW58S77og3nbU3hDlSG-fuoII3zr6A5pQ5FXlemI6COZQU1fw6GRHQZTcIzeuSyCy1TcwolV1qt5Rj_quMd1dKHKay3HatGIEn842gXkL2B_gfgLkVWI58Lc1TndMimPJyRbpFgc5-ibFHkxHcp9g9L3c9gN_ZnT1nUc7ENmXFWXgTJIRgEXwRklinAfJgb9bBEI4_HxCrzsAucY2AsebwJRvhm7Kgq1Y8ZiIx3M5w1U7RhFlQv6o_PBmgrTLGCnUy6O_RaE-4190eZnHPoZJJcrdZxcSsH2naRt_3LYb9MHWHM1Uvu8-AZrfhCUwpq373UBa97Vr6wuYdvQoqtyme8rCl9ZVQkqO1HDEz1x8Q5wVvOaDjuwmbJUFYPck7aoQRgkS2U1K5PjJ1q8cAhwBMgzCHd2hVm5tIxxHJttxQ9V1e0ZiB8Bzgwll8mXbh8U_ATw86j_9m2cT5tuv8lfc0E3rJZUNIJKKlRPl316oAcuqLt_QQ_U7ZmmvG7OVOx5S0G4e1K4rD7CQ1cXkvEa9hmNlsesSHE-ZRFuVOu_SAGjEMQPgzaKHyCOlAc-1jOn9WRU8ga4YcXXUqWbqaFkpkbwkhpKDGpeDXQSrKbszcEOf45dNpNTnprJZSY3n2zaixpex90qhjp6RtZ0UYf9R1rbWGXaN-YUYnEkj5bgS8uP5TdHJUuWSHzwHytyjkqWZpH54JGp0oV-VFsTdcI61dFhr3IysGQir6uRJRh53WbLpn4X2CKSn6ypSl8RSsiSmFDqxd9-JpqwLUFtfS1gz33BekBhW6JC3hZ8Vwl4rQWvBowukmziasxUZy09eOuqtaLYusy94i2KXeZeITd1Wfs13chl7pV3TSrrOi9xYBNLMLxkmJnL3BTYySTtYFdcEFNsJ9PIYldA2Oqwf9o4hGLvBLA1Y38o2_LxIP47bW-Y5g5R2cvX1pf9fG2p2c_XVp39fCNbyvfztVV9P19r3Nx8r9fAHbu_Vw6PZp15dUG6Qhl3LQM3iuSu1e1WwTxyOfkT2rlr4fmEjO5YkT6hqLsW8E-I664F7xM6-5prbtDcXevp7fJ7ZC6cnxPiLdesafJPb0y6DmvLY9_uIPvfC62eBofD680nwesV7aFX6nyvqZiOwnhqX9O_x7xgfKEdsWyt3GX7J0nO_x3dfHblbHBt6eJq8-PS6x5p-y8qyF8fWdc6avLF5ej5gcofgf9Zlf_2WPx4SJahmPzU24PYjlnz9uC2aLqtM-najURi3UgsqKzfH3gKa1Sya245Ujuw_ka3HD_qvj-nsByE7cr9S3-QNO5f_vo9GhWs66-GHEcE_-FCl4I08ffqKx7_ldH2Mvu1RHCUz3749siVhrhvkqZUEGGrjutayZsDhrvfHqAU7HikgpaA7OCvwz1JPi0I57zq6AhBS_jK5AtkpxMtWS4p_O0hAOHuq8yLb2o4HTcKd-U9Kbdkm9_Re5SSJM5QGkV3L_f7PI3Vv-JAkjhO4zjfF3F-yNIShWlUlnfsHoc4DhFSz9swCjJK4yzOSBJvUYqSLYhCespZFfTO5uJ4x9q2o_cI4zgjd1W-p1Xb_1Ye4xNrC35qWJWr_ve_NPkCMFY1Adl9_ccv_7784Pzy8UhrKnLV6_07PHTfx2_x4524729a9t2xVWPNWtnOJCSTVf8TfR01foT_1EjcdaK6X7nW6bmNdzqN4H_QQgL83HexBfh57OX5Hv8nAAD__xRKL2M">