Fix AArch64 float stack alignment (#136)

mkeeter · Jun 6, 2024 · f8d725f · f8d725f
1 parent 7e33453
commit f8d725f
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diff --git a/CHANGELOG.md b/CHANGELOG.md
@@ -1,6 +1,8 @@
 # 0.3.2 (unreleased)
 - Added `impl IntoNode for Var`, to make handling `Var` values in a context
   easier.
+- Fix possible corruption of `x24` during AArch64 float slice JIT evaluation,
+  due to incorrect stack alignment.
 
 # 0.3.1
 The highlight of this release is the `fidget::solver` module, which implements

diff --git a/fidget/src/jit/aarch64/float_slice.rs b/fidget/src/jit/aarch64/float_slice.rs
@@ -35,7 +35,8 @@ pub const SIMD_WIDTH: usize = 4;
 /// ```text
 /// | Position | Value        | Notes                                       |
 /// |----------|--------------|---------------------------------------------|
-/// | 0x228    | ...          | Register spills live up here                |
+/// | 0x230    | ...          | Register spills live up here                |
+/// | 0x228    | ---          | Padding for 16-byte alignment               |
 /// |----------|--------------|---------------------------------------------|
 /// | 0x220    | `x24`        | Backup for callee-saved register            |
 /// | 0x218    | `x23`        |                                             |
@@ -80,7 +81,7 @@ pub const SIMD_WIDTH: usize = 4;
 /// | 0x8      | `sp` (`x30`) | Stack frame                                 |
 /// | 0x0      | `fp` (`x29`) | [current value for sp]                      |
 /// ```
-const STACK_SIZE: u32 = 0x228;
+const STACK_SIZE: u32 = 0x230;
 
 impl Assembler for FloatSliceAssembler {
     type Data = f32;