mirror/zig
1
0
Fork 0
mirror of https://github.com/ziglang/zig.git synced 2026-02-12 20:37:54 +00:00
Code Issues Packages Projects Releases Wiki Activity

wasm: correctly get the type of a local for free

Browse Source 
When determining the type of a local (read: register), we would
previously subtract the stack locals also. However, this locals
are also within the same `locals` list, meaning the type of the
local we were retrieving was off by 2. This could create a validation
error when we re-use a local of a different type.
This commit is contained in:
Luuk de Gram 2022-10-15 18:56:58 +02:00
parent e62bb1d689
commit 6fcd72355c
No known key found for this signature in database
GPG Key ID: A8CFE58E4DC7D664
1 changed files with 2 additions and 2 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

4
src/arch/wasm/CodeGen.zig
View File

@ -106,8 +106,8 @@ const WValue = union(enum) {
fn free(value: *WValue, gen: *Self) void {
if (value.* != .local) return;
const local_value = value.local.value;
const reserved = gen.args.len + @boolToInt(gen.return_value != .none) + 2; // 2 for stack locals
if (local_value < reserved) return; // reserved locals may never be re-used.
const reserved = gen.args.len + @boolToInt(gen.return_value != .none);
if (local_value < reserved + 2) return; // reserved locals may never be re-used. Also accounts for 2 stack locals.
const index = local_value - reserved;
const valtype = @intToEnum(wasm.Valtype, gen.locals.items[index]);