compiler

Unnamed Compiled Systems Language Project
git clone http://frotz.net/git/compiler.git
Log | Files | Refs

notes.txt (2150B)

      1 
      2 Tracking Source Location
      3 ------------------------
      4 LLVM Source Location is u32
      5 - "sourcemanager" assigns files into global offset space
      6 - high bit == macro expansion (separate space)
      7 - 0 = invalid (errors not related to source like command line options)
      8 
      9 
     10 Register Allocation
     11 -------------------
     12 aho 2e pdf p565  8.5 -- a simple code generator
     13 mogensen 2017 p130 -- simple IR
     14 
     15 Register Spilling and Live-Range Splitting for SSA-Form Programs
     16 Braun / Hack 2009
     17 - adapts furtherst-first algo to ssa use, no coloring needed
     18 
     19 Phys vs Virt Registers
     20 ----------------------
     21 mogensen 2017 / 8.6.2 (p198pdf)
     22 - phys regs can be used "pre-colored" for instructions with
     23   limitations, func call params, etc
     24 - "live range splitting" by inserting moves from colorless to pre-colored regs
     25 
     26 cmu compilers class 2018 / register selection lecture
     27 - similar comments re: special instructions, func calls, etc
     28 
     29 
     30 Live Analysis
     31 -------------
     32 torczon 2012  8.6.1 finding uninit vars w/ live info (p470pdf)
     33 LiveOut / UEVar / VarKill  iterative method
     34 
     35 mogenson 2017 8.2 liveness analysis (p188pdf)
     36 
     37 cmu compilers 2018 - 05-liveness-analysis.pdf
     38 
     39 
     40 Constant Folding
     41 ----------------
     42 simple constant folding
     43 
     44   *    ->  C(C1*C2)
     45  / \
     46 C1  C2
     47 
     48 more complex const folding (various algebraic transforms, etc)
     49 
     50   *   ->    *
     51  / \       / \
     52 C1  *    V1   C(C1*C2)
     53    / \
     54   V1  C2
     55 
     56 
     57 Assorted Resources
     58 ------------------
     59 https://groups.seas.harvard.edu/courses/cs153/2019fa/schedule.html
     60 https://blog.yossarian.net/2020/10/23/Understanding-static-single-assignment-forms
     61 https://lowlevelbits.org/how-to-learn-compilers-llvm-edition/
     62 
     63 Tiny Scheme / 5k repl
     64 ---------------------
     65 http://www.iro.umontreal.ca/~feeley/papers/YvonFeeleyVMIL21.pdf
     66 https://github.com/udem-dlteam/ribbit
     67 
     68 
     69 Code Snippets
     70 -------------
     71 
     72 int fib(int n) {
     73     int a = 0;
     74     int b = 1;
     75     int z = 0;
     76     while (n != z) {
     77         int t = a + b;
     78         a = b;
     79         b = t;
     80         n = n - 1;
     81         z = 0;
     82     }
     83     return a;
     84 }
     85 
     86 int gcd(int x1, int x2) {
     87     while (x2 != 0) {
     88         int q = x1 / x2;
     89         int t = q * x2;
     90         int r = x1 - t;
     91         x1 = x2;
     92         x2 = r;
     93     }
     94     return x1;
     95 }
     96