dmd codegen improvements

[qznc via Digitalmars-d]

On Wednesday, 19 August 2015 at 11:22:09 UTC, Dmitry Olshansky 
wrote:
> On 18-Aug-2015 15:37, Vladimir Panteleev wrote:
>> I think stability of the DMD backend is a goal of much higher 
>> value than
>> the performance of the code it emits. DMD is never going to 
>> match the
>> code generation quality of LLVM and GCC, which have had many, 
>> many
>> man-years invested in them. Working on DMD optimizations is 
>> essentially
>> duplicating this work, and IMHO I think it's not only a waste 
>> of time,
>> but harmful to D because of the risk of regressions.
>
> How about stress-testing with some simple fuzzer:
> 1. Generate a sequence of pluasable expressions/functions.
> 2. Spit out results via printf.
> 3. Permute -O -inline and compare the outputs.

Tools like csmith [0] are surprisingly good at finding ICEs, but 
useless for performance regressions.
A "dsmith" would probably find lots of bugs in the dmd backend.

[0] https://embed.cs.utah.edu/csmith/