[torch.prod] Incorrect cpu calculation results for torch.prod

[wbscd]

🐛 Describe the bug

import torch

x = torch.zeros((1, 1, 16, 16), dtype=torch.bool)
y = torch.prod(x, dtype=torch.bool)

print(y)
# Get `tensor(True)` as result but the result should be `tensor(False)` obviously.

Versions

Collecting environment information...
PyTorch version: 2.3.0+cu121
Is debug build: False
CUDA used to build PyTorch: 12.1
ROCM used to build PyTorch: N/A

OS: Ubuntu 22.04.3 LTS (x86_64)
GCC version: (Ubuntu 11.4.0-1ubuntu1~22.04) 11.4.0
Clang version: 14.0.0-1ubuntu1.1
CMake version: version 3.28.1
Libc version: glibc-2.35

Python version: 3.9.16 (main, May 15 2023, 23:46:34) [GCC 11.2.0] (64-bit runtime)
Python platform: Linux-5.10.16.3-microsoft-standard-WSL2-x86_64-with-glibc2.35
Is CUDA available: True
CUDA runtime version: Could not collect
CUDA_MODULE_LOADING set to: LAZY
GPU models and configuration: GPU 0: NVIDIA GeForce MX570
Nvidia driver version: 546.80
cuDNN version: Could not collect
HIP runtime version: N/A
MIOpen runtime version: N/A
Is XNNPACK available: True

CPU:
Architecture: x86_64
CPU op-mode(s): 32-bit, 64-bit
Address sizes: 39 bits physical, 48 bits virtual
Byte Order: Little Endian
CPU(s): 16
On-line CPU(s) list: 0-15
Vendor ID: GenuineIntel
Model name: 12th Gen Intel(R) Core(TM) i7-1260P
CPU family: 6
Model: 154
Thread(s) per core: 2
Core(s) per socket: 8
Socket(s): 1
Stepping: 3
BogoMIPS: 4992.01
Flags: fpu vme de pse tsc msr pae mce cx8 apic sep mtrr pge mca cmov pat pse36 clflush mmx fxsr sse sse2 ss ht syscall nx pdpe1gb rdtscp lm constant_tsc rep_good nopl xtopology tsc_reliable nonstop_tsc cpuid pni pclmulqdq vmx ssse3 fma cx16 pcid sse4_1 sse4_2 x2apic movbe popcnt tsc_deadline_timer aes xsave avx f16c rdrand hypervisor lahf_lm abm 3dnowprefetch invpcid_single ssbd ibrs ibpb stibp ibrs_enhanced tpr_shadow vnmi ept vpid ept_ad fsgsbase tsc_adjust bmi1 avx2 smep bmi2 erms invpcid rdseed adx smap clflushopt clwb sha_ni xsaveopt xsavec xgetbv1 xsaves umip waitpkg gfni vaes vpclmulqdq rdpid movdiri movdir64b fsrm md_clear serialize flush_l1d arch_capabilities
Virtualization: VT-x
Hypervisor vendor: Microsoft
Virtualization type: full
L1d cache: 384 KiB (8 instances)
L1i cache: 256 KiB (8 instances)
L2 cache: 10 MiB (8 instances)
L3 cache: 18 MiB (1 instance)
Vulnerability Itlb multihit: Not affected
Vulnerability L1tf: Not affected
Vulnerability Mds: Not affected
Vulnerability Meltdown: Not affected
Vulnerability Spec store bypass: Mitigation; Speculative Store Bypass disabled via prctl and seccomp
Vulnerability Spectre v1: Mitigation; usercopy/swapgs barriers and __user pointer sanitization
Vulnerability Spectre v2: Mitigation; Enhanced IBRS, IBPB conditional, RSB filling
Vulnerability Srbds: Not affected
Vulnerability Tsx async abort: Not affected

Versions of relevant libraries:
[pip3] numpy==1.21.5
[pip3] torch==2.3.0
[pip3] torchaudio==2.1.1+cu121
[pip3] torchvision==0.16.1+cu121
[pip3] triton==2.3.0
[conda] numpy 1.21.5 pypi_0 pypi
[conda] torch 2.3.0 pypi_0 pypi
[conda] torchaudio 2.1.1+cu121 pypi_0 pypi
[conda] torchvision 0.16.1+cu121 pypi_0 pypi
[conda] triton 2.3.0 pypi_0 pypi

cc @ezyang @gchanan @zou3519 @kadeng @msaroufim

[albanD]

Note that this is due to the dtype= argument on torch.prod. Without this argument this works just fine.
Also the current code only fails if you have "nb_elem % 256 == 0"

[mingfeima]

@zhuhaozhe please help fix this one!

[zhuhaozhe]

Rootcaused here

pytorch/aten/src/ATen/native/cpu/ReduceOpsKernel.cpp

Line 162 in b054470

__ubsan_ignore_undefined__ { return a && b; },

the && are not override for Vectorized<bool> and will return True here even both a and b are all Falses, will submit a PR for it.