From 7764ca63040186f02411516448f8e7f81236fc0c Mon Sep 17 00:00:00 2001
From: Russel Arbore <russel.jma@gmail.com>
Date: Sun, 16 Feb 2025 18:19:50 -0600
Subject: [PATCH] Use larger alignment for arrays
---
hercules_cg/src/cpu.rs | 6 ++----
hercules_cg/src/lib.rs | 5 +++--
hercules_rt/src/lib.rs | 6 ++++--
3 files changed, 9 insertions(+), 8 deletions(-)
diff --git a/hercules_cg/src/cpu.rs b/hercules_cg/src/cpu.rs
index a19218c7..f90657a4 100644
--- a/hercules_cg/src/cpu.rs
+++ b/hercules_cg/src/cpu.rs
@@ -507,11 +507,10 @@ impl<'a> CPUContext<'a> {
// load.
write!(
body,
- " {} = load {}, ptr {}, align {}\n",
+ " {} = load {}, ptr {}\n",
self.get_value(id, false),
self.get_type(self_ty),
index_ptr_name,
- get_type_alignment(self.types, collect_ty),
)?;
} else {
// If this read doesn't reach a primitive type, just return
@@ -540,10 +539,9 @@ impl<'a> CPUContext<'a> {
// perform a single store of the data value.
write!(
body,
- " store {}, ptr {}, align {}\n",
+ " store {}, ptr {}\n",
self.get_value(data, true),
index_ptr_name,
- get_type_alignment(self.types, collect_ty),
)?;
} else {
// If the data item being written is not a primitive type,
diff --git a/hercules_cg/src/lib.rs b/hercules_cg/src/lib.rs
index 15946f72..af2420d8 100644
--- a/hercules_cg/src/lib.rs
+++ b/hercules_cg/src/lib.rs
@@ -16,7 +16,7 @@ use std::collections::BTreeMap;
use hercules_ir::*;
-pub const LARGEST_ALIGNMENT: usize = 8;
+pub const LARGEST_ALIGNMENT: usize = 32;
/*
* The alignment of a type does not depend on dynamic constants.
@@ -33,7 +33,8 @@ pub fn get_type_alignment(types: &Vec<Type>, ty: TypeID) -> usize {
.map(|id| get_type_alignment(types, *id))
.max()
.unwrap_or(1),
- Type::Array(elem, _) => get_type_alignment(types, elem),
+ // Use a large alignment for arrays to generate better vector code.
+ Type::Array(_, _) => LARGEST_ALIGNMENT,
}
}
diff --git a/hercules_rt/src/lib.rs b/hercules_rt/src/lib.rs
index f8fdf2ef..0c3ffd80 100644
--- a/hercules_rt/src/lib.rs
+++ b/hercules_rt/src/lib.rs
@@ -13,8 +13,10 @@ use std::sync::OnceLock;
* src/rt.rs (the RT backend).
*/
+pub const LARGEST_ALIGNMENT: usize = 32;
+
pub unsafe fn __cpu_alloc(size: usize) -> *mut u8 {
- let ptr = alloc(Layout::from_size_align(size, 16).unwrap());
+ let ptr = alloc(Layout::from_size_align(size, LARGEST_ALIGNMENT).unwrap());
if cfg!(feature = "debug") {
eprintln!("__cpu_alloc: {:?}, {}", ptr, size);
assert!(!ptr.is_null() || size == 0);
@@ -27,7 +29,7 @@ pub unsafe fn __cpu_dealloc(ptr: *mut u8, size: usize) {
eprintln!("__cpu_dealloc: {:?}, {}", ptr, size);
assert!(!ptr.is_null() || size == 0);
}
- dealloc(ptr, Layout::from_size_align(size, 16).unwrap())
+ dealloc(ptr, Layout::from_size_align(size, LARGEST_ALIGNMENT).unwrap())
}
pub unsafe fn __cpu_zero_mem(ptr: *mut u8, size: usize) {
--
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