language-servers/roc
1
0
Fork 0
mirror of https://github.com/roc-lang/roc.git synced 2025-08-01 10:52:18 +00:00
Code Issues Projects Releases Packages Wiki Activity Actions 6

Pull out string literal creation

Browse source
This commit is contained in:
Ayaz Hafiz 2022-11-22 15:09:31 -06:00
parent d7db10d7b5
commit 2b49aee3d2
No known key found for this signature in database
GPG key ID: 0E2A37416A25EF58
1 changed files with 42 additions and 39 deletions
Download patch file Download diff file Expand all files Collapse all files

81
crates/compiler/gen_wasm/src/backend.rs
View file

@ -1128,45 +1128,7 @@ impl<'a> WasmBackend<'a> {
let (local_id, offset) =
location.local_and_offset(self.storage.stack_frame_pointer);
let len = string.len();
if len < 12 {
// Construct the bytes of the small string
let mut bytes = [0; 12];
bytes[0..len].clone_from_slice(string.as_bytes());
bytes[11] = 0x80 | (len as u8);
// Transform into two integers, to minimise number of instructions
let bytes_split: &([u8; 8], [u8; 4]) =
unsafe { std::mem::transmute(&bytes) };
let int64 = i64::from_le_bytes(bytes_split.0);
let int32 = i32::from_le_bytes(bytes_split.1);
// Write the integers to memory
self.code_builder.get_local(local_id);
self.code_builder.i64_const(int64);
self.code_builder.i64_store(Align::Bytes4, offset);
self.code_builder.get_local(local_id);
self.code_builder.i32_const(int32);
self.code_builder.i32_store(Align::Bytes4, offset + 8);
} else {
let bytes = string.as_bytes();
let elements_addr = self.store_bytes_in_data_section(bytes);
// ptr
self.code_builder.get_local(local_id);
self.code_builder.i32_const(elements_addr as i32);
self.code_builder.i32_store(Align::Bytes4, offset);
// len
self.code_builder.get_local(local_id);
self.code_builder.i32_const(string.len() as i32);
self.code_builder.i32_store(Align::Bytes4, offset + 4);
// capacity
self.code_builder.get_local(local_id);
self.code_builder.i32_const(string.len() as i32);
self.code_builder.i32_store(Align::Bytes4, offset + 8);
};
self.expr_string_literal(string, local_id, offset);
}
// Bools and bytes should not be stored in the stack frame
Literal::Bool(_) | Literal::Byte(_) => invalid_error(),
@ -1177,6 +1139,47 @@ impl<'a> WasmBackend<'a> {
};
}
fn expr_string_literal(&mut self, string: &str, local_id: LocalId, offset: u32) {
let len = string.len();
if len < 12 {
// Construct the bytes of the small string
let mut bytes = [0; 12];
bytes[0..len].clone_from_slice(string.as_bytes());
bytes[11] = 0x80 | (len as u8);
// Transform into two integers, to minimise number of instructions
let bytes_split: &([u8; 8], [u8; 4]) = unsafe { std::mem::transmute(&bytes) };
let int64 = i64::from_le_bytes(bytes_split.0);
let int32 = i32::from_le_bytes(bytes_split.1);
// Write the integers to memory
self.code_builder.get_local(local_id);
self.code_builder.i64_const(int64);
self.code_builder.i64_store(Align::Bytes4, offset);
self.code_builder.get_local(local_id);
self.code_builder.i32_const(int32);
self.code_builder.i32_store(Align::Bytes4, offset + 8);
} else {
let bytes = string.as_bytes();
let elements_addr = self.store_bytes_in_data_section(bytes);
// ptr
self.code_builder.get_local(local_id);
self.code_builder.i32_const(elements_addr as i32);
self.code_builder.i32_store(Align::Bytes4, offset);
// len
self.code_builder.get_local(local_id);
self.code_builder.i32_const(string.len() as i32);
self.code_builder.i32_store(Align::Bytes4, offset + 4);
// capacity
self.code_builder.get_local(local_id);
self.code_builder.i32_const(string.len() as i32);
self.code_builder.i32_store(Align::Bytes4, offset + 8);
};
}
/// Create a string constant in the module data section
/// Return the data we need for code gen: linker symbol index and memory address
fn store_bytes_in_data_section(&mut self, bytes: &[u8]) -> u32 {