radiance · commit

Reclaim unused memory after i-sel

fcb3c9b35f20da1d396ab756d7ff877f529f3a532067bd697e459ed3c46623a4

Re-use memory for function instruction selection.

Alexis Sellier committed 1 month ago 1 parent 9cb6526b

lib/std/arch/rv64.rad +4 -0

    let dataSyms = storage.dataSyms[..dataSymCount];

    for i in 0..program.fns.len {
        let func = program.fns[i];
        if not func.isExtern {
            let checkpoint = alloc::save(arena);
            let ralloc = try! regalloc::allocate(func, &config, arena);
            isel::selectFn(&mut e, dataSyms, &ralloc, func);

            // Reclaim unused memory after instruction selection.
            alloc::restore(arena, checkpoint);
        }
    }
    // Patch entry jump now that we know where the default function is.
    // Nb. we use a two-instruction jump even if it isn't always needed.
    if let target = defaultName {

lib/std/lang/alloc.rad +11 -0

/// Does not zero the memory.
pub fn reset(arena: *mut Arena) {
    arena.offset = 0;
}

/// Save the current arena state for later restoration.
pub fn save(arena: *Arena) -> u32 {
    return arena.offset;
}

/// Restore the arena to a previously saved state, reclaiming all
/// allocations made since that point.
pub fn restore(arena: *mut Arena, savedOffset: u32) {
    arena.offset = savedOffset;
}

/// Returns the number of bytes currently allocated.
pub fn used(arena: *Arena) -> u32 {
    return arena.offset;
}


336	336		let dataSyms = storage.dataSyms[..dataSymCount];
337	337
338	338		for i in 0..program.fns.len {
339	339		let func = program.fns[i];
340	340		if not func.isExtern {
	341	+	let checkpoint = alloc::save(arena);
341	342		let ralloc = try! regalloc::allocate(func, &config, arena);
342	343		isel::selectFn(&mut e, dataSyms, &ralloc, func);
	344	+
	345	+	// Reclaim unused memory after instruction selection.
	346	+	alloc::restore(arena, checkpoint);
343	347		}
344	348		}
345	349		// Patch entry jump now that we know where the default function is.
346	350		// Nb. we use a two-instruction jump even if it isn't always needed.
347	351		if let target = defaultName {

57	57		/// Does not zero the memory.
58	58		pub fn reset(arena: *mut Arena) {
59	59		arena.offset = 0;
60	60		}
61	61
	62	+	/// Save the current arena state for later restoration.
	63	+	pub fn save(arena: *Arena) -> u32 {
	64	+	return arena.offset;
	65	+	}
	66	+
	67	+	/// Restore the arena to a previously saved state, reclaiming all
	68	+	/// allocations made since that point.
	69	+	pub fn restore(arena: *mut Arena, savedOffset: u32) {
	70	+	arena.offset = savedOffset;
	71	+	}
	72	+
62	73		/// Returns the number of bytes currently allocated.
63	74		pub fn used(arena: *Arena) -> u32 {
64	75		return arena.offset;
65	76		}
66	77