Code generation¶
The module ppci.codegen provides functions and classes to generate
code.
Back-end¶
The back-end is more complicated. There are several steps to be taken here.
- Tree creation
- Instruction selection
- Register allocation
- Peep hole optimization
![digraph codegen {
1 [label="IR-code"]
10 [label="irdag"]
20 [label="dagsplitter"]
30 [label="instruction selector"]
40 [label="register allocator"]
49 [label="assembly parser"]
50 [label="outstream"]
60 [label="object file"]
61 [label="text output"]
1 -> 10
10 -> 20 [label="Selection DAG"]
20 -> 30 [label="Selection Trees"]
30 -> 40 [label="frame"]
40 -> 50 [label="frame"]
49 -> 50
50 -> 60
50 -> 61
}](../../_images/graphviz-edc8fe3290c9f1485d39d1e1e21fa0e1f96c5213.png)
Canonicalize¶
During this phase, the IR-code is made simpler. Also unsupported operations are rewritten into function calls. For example, soft floating point is introduced here.
