add diag layer and its converter

[wnqn1597]

No description provided.

[nihui]

add pnnx ncnn tests
update docs operators.md

[codecov-commenter]

Codecov Report

Merging #4935 (9f9040b) into master (695f770) will decrease coverage by 0.01%.
The diff coverage is 95.34%.

@@            Coverage Diff             @@
##           master    #4935      +/-   ##
==========================================
- Coverage   94.72%   94.72%   -0.01%     
==========================================
  Files         770      771       +1     
  Lines      228715   228758      +43     
==========================================
+ Hits       216645   216685      +40     
- Misses      12070    12073       +3     

Files Changed	Coverage Δ
src/layer/diag.cpp	95.34% <95.34%> (ø)

... and 1 file with indirect coverage changes

📢 Have feedback on the report? Share it here.

[nihui]

pass_ncnn/torch_diag.cpp doesn't seem to work for some reasons, see pnnx ci errors

[wnqn1597]

pass_ncnn/torch_diag.cpp doesn't seem to work for some reasons, see pnnx ci errors

Can I take a look at the logs of pnnx ci?

[nihui]

pass_ncnn/torch_diag.cpp doesn't seem to work for some reasons, see pnnx ci errors

Can I take a look at the logs of pnnx ci?

click into pnnx ci, login with your github, and you could see the log there

[nihui]

 446/507 Test #450: test_ncnn_torch_diag ..........................***Failed    5.55 sec
pnnxparam = test_torch_diag.pnnx.param
pnnxbin = test_torch_diag.pnnx.bin
pnnxpy = test_torch_diag_pnnx.py
pnnxonnx = test_torch_diag.pnnx.onnx
ncnnparam = test_torch_diag.ncnn.param
ncnnbin = test_torch_diag.ncnn.bin
ncnnpy = test_torch_diag_ncnn.py
fp16 = 1
optlevel = 2
device = cpu
inputshape = [7]f32,[5,5]f32,[4,8]f32
inputshape2 = 
customop = 
moduleop = 
############# pass_level0

----------------

############# pass_level1
############# pass_level2
############# pass_level3
############# pass_level4
############# pass_level5
############# pass_ncnn
force batch axis 233 for operand 0
force batch axis 233 for operand 4
force batch axis 233 for operand 3
fallback batch axis 233 for operand 1
fallback batch axis 233 for operand 2
fallback batch axis 233 for operand 5
ignore torch.diag torch.diag_2 param diagonal=3
ignore torch.diag torch.diag_1 param diagonal=0
ignore torch.diag torch.diag_0 param diagonal=-1
layer torch.diag not exists or registered
CMake Error at /data/devops/workspace/tools/pnnx/tests/run_test.cmake:5 (message):
  Test failed with return value 'Segmentation fault'

[nihui]

lgtm

[nihui]

Thanks for your contribution !