Internships/ProjectIdeas/TCGCodeQuality: Difference between revisions

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Improving the code generation of the TCG backend is a hard task that involves reading through large amounts of text looking for anomalies in the generated code. It would be nice to have tools to more readily extract and parse code generation information. This would include:
Improving the code generation of the TCG backend is a hard task that involves reading through large amounts of text looking for anomalies in the generated code. It would be nice to have tools to more readily extract and parse code generation information. This would include:


* which are hot blocks (frequently run, hence more important performance wise)
* which are hot blocks (frequently run, hence more important performance wise)
* how many fills/spills in a block (where register contents are moved due to register pressure)
* how many fills/spills in a block (where register contents are moved due to register pressure)
* number of host instructions for each guest instruction (JIT profiling has a basic version of this)
* number of host instructions for each guest instruction (JIT profiling has a basic version of this)
* elide or beautify common blocks like softmmu access macros (which are always the same)
* elide or beautify common blocks like softmmu access macros (which are always the same)
* support interactive exploration of translation state (system emulation)
* support interactive exploration of translation state (system emulation)
 
'''Links:'''
This work could be a pre-cursor to supporting [[Internships/ProjectIdeas/Multi-exit Hot Blocks]]
* [[Documentation/TCG]]
 
'''Links:'''
'''Details:'''
* [[Documentation/TCG]]
* Skill level: intermediate or advanced, understanding of code generation (compilers/JITs)
 
* Language: C, Assembly (x86 or preferred host)
'''Details:'''
* Mentor: alex.bennee@linaro.org / stsquad on IRC
* Skill level: intermediate or advanced, understanding of code generation (compilers/JITs)
* Suggested by: Alex Bennée
* Language: C, Assembly (x86 or preferred host)
* Mentor: alex.bennee@linaro.org / stsquad on IRC
* Suggested by: Alex Bennée

Revision as of 16:46, 15 January 2019

Measure Tiny Code Generation Quality

Summary: Improve the diagnostics tools to asses code quality

Improving the code generation of the TCG backend is a hard task that involves reading through large amounts of text looking for anomalies in the generated code. It would be nice to have tools to more readily extract and parse code generation information. This would include:

  • which are hot blocks (frequently run, hence more important performance wise)
  • how many fills/spills in a block (where register contents are moved due to register pressure)
  • number of host instructions for each guest instruction (JIT profiling has a basic version of this)
  • elide or beautify common blocks like softmmu access macros (which are always the same)
  • support interactive exploration of translation state (system emulation)

This work could be a pre-cursor to supporting Internships/ProjectIdeas/Multi-exit Hot Blocks

Links:

Details:

  • Skill level: intermediate or advanced, understanding of code generation (compilers/JITs)
  • Language: C, Assembly (x86 or preferred host)
  • Mentor: alex.bennee@linaro.org / stsquad on IRC
  • Suggested by: Alex Bennée