simplify program error

[publicqi]

current ProgramError is copied from solana-sdk which is super redundant.

this PR refactors ProgramError. it uses one u8 as the discriminator, and an optional 4 bytes for custom error code.

For u64 to ProgramError conversion, previously the code generated was huge:

Now it simplifies to

And for ProgramError to u64 conversion (i.e. return of entrypoint), the code reduced from

to

[febo]

@publicqi Did you check the impact on the program size and CU? I did a quick test and it seems that the "simplified" version increases the program size by ~1kb and CU by 2. Not a lot, but I was expecting the opposite.

[publicqi]

do you have an example program? i checked and the size actually went down. maybe we should add some base examples in the repo to reflect improvements

also i’m digging into some rustc issues. it seems that impl display for u64 occupied a lot of space

[febo]

do you have an example program? i checked and the size actually went down. maybe we should add some base examples in the repo to reflect improvements

I did an ad-hoc test with an existing program that I have. Maybe we could use this one to test: https://github.com/febo/ping

[publicqi]

i am comparing ping program between master(01c1c7a) with this branch (4160b7e).

number of ebpf instruction reduced from 717 to 652. size of the elf reduced from 8424 bytes to 7720 bytes.

no other changes to the ping program except for some dependency updates

diff --git a/program/Cargo.toml b/program/Cargo.toml
index df1c7bf..0cb6ce9 100644
--- a/program/Cargo.toml
+++ b/program/Cargo.toml
@@ -15,4 +15,5 @@ account-dependencies = []
 crate-type = ["cdylib", "lib"]
 
 [dependencies]
-pinocchio = { version="^0", features=["macro"], git="https://github.com/febo/pinocchio.git" }
+pinocchio = { path = "../../pinocchio/sdk/pinocchio" }
+pinocchio-pubkey = { path = "../../pinocchio/sdk/pubkey" }
\ No newline at end of file
diff --git a/program/src/lib.rs b/program/src/lib.rs
index 1b679f7..db2c49a 100644
--- a/program/src/lib.rs
+++ b/program/src/lib.rs
@@ -1,5 +1,7 @@
+use pinocchio_pubkey::declare_id;
+
 pub mod entrypoint;
 pub mod instruction;
 pub mod processor;
 
-pinocchio::declare_id!("Ping111111111111111111111111111111111111111");
+declare_id!("Ping111111111111111111111111111111111111111");

toolchain version:

cargo build-sbf -V
solana-cargo-build-sbf 2.1.14
platform-tools v1.43
rustc 1.79.0

[publicqi]

so the program size both in number of ebpf instruction emitted and the elf size reduced.

how did you compare the CU?

[febo]

so the program size both in number of ebpf instruction emitted and the elf size reduced.

how did you compare the CU?

I executed an instruction that generates an error, so it triggers the conversion to u64.

[publicqi]

emm that's probably because in the old code, the ProgramError -> u64 conversion is just branch matching (see screenshot above). in the new code it's now doing shifting. can you try for all types of program errors what are the diffs? i would expect some conversion will take a bit more, but the size should reduce by a lot.