| This is a list of things that need to be worked on. It will hopefully |
| be complete soon. |
| |
| Coverage |
| -------- |
| |
| Correctness |
| ----------- |
| - Debugging info (check & fix as much as we can) |
| - @ directive in rewrites might read overwritten data. Save @loc |
| in variable before modifying v. |
| |
| Optimizations (better compiled code) |
| ------------------------------------ |
| - Reduce register pressure in scheduler |
| - More strength reduction: multiply -> shift/add combos (Worth doing?) |
| - Add a value range propagation pass (for bounds elim & bitwidth reduction) |
| - Make dead store pass inter-block |
| - redundant CMP in sequences like this: |
| SUBQ $8, AX |
| CMP AX, $0 |
| JEQ ... |
| - If there are a lot of MOVQ $0, ..., then load |
| 0 into a register and use the register as the source instead. |
| - Allow arrays of length 1 (or longer, with all constant indexes?) to be SSAable. |
| - Figure out how to make PARAMOUT variables ssa-able. |
| They need to get spilled automatically at end-of-function somehow. |
| - If strings are being passed around without being interpreted (ptr |
| and len feilds being accessed) pass them in xmm registers? |
| Same for interfaces? |
| - OpArrayIndex should take its index in AuxInt, not a full value. |
| - remove FLAGS from REP instruction clobbers |
| - (x86) Combine loads into other ops |
| Note that this is challenging for ops that generate flags |
| because flagalloc wants to move those instructions around for |
| flag regeneration. |
| - In forms like if ... { call } else { no call }, mark the call branch as unlikely. |
| - Non-constant rotate detection. |
| |
| Optimizations (better compiler) |
| ------------------------------- |
| - Smaller Value.Type (int32 or ptr)? Get rid of types altogether? |
| - OpStore uses 3 args. Increase the size of Value.argstorage to 3? |
| - Constant cache |
| - Handle signed division overflow and sign extension earlier |
| - Implement 64 bit const division with high multiply, maybe in the frontend? |
| - Add bit widths to complex ops |
| |
| Regalloc |
| -------- |
| - Make less arch-dependent |
| - Allow return values to be ssa-able |
| - Handle 2-address instructions |
| - Make liveness analysis non-quadratic |
| |
| Future/other |
| ------------ |
| - Start another architecture (arm?) |
| - 64-bit ops on 32-bit machines |
| - Investigate type equality. During SSA generation, should we use n.Type or (say) TypeBool? |
| - Should we get rid of named types in favor of underlying types during SSA generation? |
| - Should we introduce a new type equality routine that is less strict than the frontend's? |
| - Infrastructure for enabling/disabling/configuring passes |
