`printf` debugging#

Not the most elegant, but certainly the fastest, the easiest approach is to figure out what code path and function call is expected.

Here’s a simple example, focusing on syrk, which of course applies to updates of the form:

For the make build:

python optest.py --test expected_outputs.json.gz
TRANS: DEFINED
syrk_beta called with parameters:
m_from: 0, m_to: 4, n_from: 0, n_to: 4
alpha: 0.000000
ldc: 4
COMPLEX: NOT DEFINED
LOWER: DEFINED
After adjusting:
m_to: 4, n_to: 4
Iteration 0: Entering SCAL_K with MIN(4, 4)
Updated c pointer
Iteration 1: Entering SCAL_K with MIN(3, 4)
Updated c pointer
Iteration 2: Entering SCAL_K with MIN(2, 4)
Updated c pointer
Iteration 3: Entering SCAL_K with MIN(1, 4)
Updated c pointer
All tests passed.

For the meson build we might get an error, perhaps:

python optest.py --test expected_outputs.json.gz
TRANS: DEFINED
syrk_beta called with parameters:
m_from: 0, m_to: 4, n_from: 0, n_to: 4
alpha: 0.000000
ldc: 4
COMPLEX: NOT DEFINED
LOWER: DEFINED
After adjusting:
m_to: 4, n_to: 4
Iteration 0: Entering SCAL_K with MIN(4, 4)
Updated c pointer
Iteration 1: Entering SCAL_K with MIN(3, 4)
Updated c pointer
Iteration 2: Entering SCAL_K with MIN(2, 4)
Updated c pointer
Iteration 3: Entering SCAL_K with MIN(1, 4)
Updated c pointer
Test failed:
Arrays are not almost equal to 7 decimals
syrk_float_lt failed
Mismatched elements: 16 / 16 (100%)
Max absolute difference among violations: 0.66221637
Max relative difference among violations: 1.47376618
 ACTUAL: array([[1.6686409, 0.9301083, 1.3368366, 0.6689696],
       [0.9301083, 1.029747 , 1.6231705, 0.7711107],
       [1.3368366, 1.6231705, 1.8134217, 1.1115525],
       [0.6689696, 0.7711107, 1.1115525, 0.5235946]], dtype=float32)
 DESIRED: array([[1.7940524, 1.4645438, 1.3868896, 0.6206155],
       [1.4645438, 1.591244 , 1.6009721, 0.3527319],
       [1.3868896, 1.6009721, 1.7777048, 0.4493361],
       [0.6206155, 0.3527319, 0.4493361, 0.4791749]])

Which is not super helpful here, given that the printf statements show no differences other than the actual test failure.

printf debugging#

`printf` debugging#