From 9a490e4e0d6c50b0f27f7844437115a92cb8f2c1 Mon Sep 17 00:00:00 2001
From: Laytan <laytanlaats@hotmail.com>
Date: Mon, 18 Dec 2023 16:38:51 +0100
Subject: [PATCH] fix big alignment

---
 core/mem/virtual/arena.odin                |  2 +-
 core/mem/virtual/virtual.odin              |  8 ++++----
 core/runtime/default_allocators_arena.odin | 12 ++++++------
 3 files changed, 11 insertions(+), 11 deletions(-)

diff --git a/core/mem/virtual/arena.odin b/core/mem/virtual/arena.odin
index bc685f0b8..90379e5e6 100644
--- a/core/mem/virtual/arena.odin
+++ b/core/mem/virtual/arena.odin
@@ -106,7 +106,7 @@ arena_alloc :: proc(arena: ^Arena, size: uint, alignment: uint, loc := #caller_l
 
 			block_size := max(needed, arena.minimum_block_size)
 
-			new_block := memory_block_alloc(needed, block_size, {}) or_return
+			new_block := memory_block_alloc(needed, block_size, alignment, {}) or_return
 			new_block.prev = arena.curr_block
 			arena.curr_block = new_block
 			arena.total_reserved += new_block.reserved
diff --git a/core/mem/virtual/virtual.odin b/core/mem/virtual/virtual.odin
index 1624fae9d..89f0d9c58 100644
--- a/core/mem/virtual/virtual.odin
+++ b/core/mem/virtual/virtual.odin
@@ -68,7 +68,7 @@ align_formula :: #force_inline proc "contextless" (size, align: uint) -> uint {
 }
 
 @(require_results)
-memory_block_alloc :: proc(committed, reserved: uint, flags: Memory_Block_Flags) -> (block: ^Memory_Block, err: Allocator_Error) {
+memory_block_alloc :: proc(committed, reserved: uint, alignment: uint, flags: Memory_Block_Flags) -> (block: ^Memory_Block, err: Allocator_Error) {
 	page_size := DEFAULT_PAGE_SIZE
 	assert(mem.is_power_of_two(uintptr(page_size)))
 
@@ -79,8 +79,8 @@ memory_block_alloc :: proc(committed, reserved: uint, flags: Memory_Block_Flags)
 	reserved  = align_formula(reserved, page_size)
 	committed = clamp(committed, 0, reserved)
 	
-	total_size     := uint(reserved + size_of(Platform_Memory_Block))
-	base_offset    := uintptr(size_of(Platform_Memory_Block))
+	total_size     := uint(reserved + max(alignment, size_of(Platform_Memory_Block)))
+	base_offset    := uintptr(max(alignment, size_of(Platform_Memory_Block)))
 	protect_offset := uintptr(0)
 	
 	do_protection := false
@@ -183,4 +183,4 @@ memory_block_dealloc :: proc(block_to_free: ^Memory_Block) {
 safe_add :: #force_inline proc "contextless" (x, y: uint) -> (uint, bool) {
 	z, did_overflow := intrinsics.overflow_add(x, y)
 	return z, !did_overflow
-}
\ No newline at end of file
+}
diff --git a/core/runtime/default_allocators_arena.odin b/core/runtime/default_allocators_arena.odin
index 3e78e7f20..4506acb56 100644
--- a/core/runtime/default_allocators_arena.odin
+++ b/core/runtime/default_allocators_arena.odin
@@ -28,11 +28,11 @@ safe_add :: #force_inline proc "contextless" (x, y: uint) -> (uint, bool) {
 }
 
 @(require_results)
-memory_block_alloc :: proc(allocator: Allocator, capacity: uint, loc := #caller_location) -> (block: ^Memory_Block, err: Allocator_Error) {
-	total_size := uint(capacity + size_of(Memory_Block))
-	base_offset    := uintptr(size_of(Memory_Block))
+memory_block_alloc :: proc(allocator: Allocator, capacity: uint, alignment: uint, loc := #caller_location) -> (block: ^Memory_Block, err: Allocator_Error) {
+	total_size  := uint(capacity + max(alignment, size_of(Memory_Block)))
+	base_offset := uintptr(max(alignment, size_of(Memory_Block)))
 
-	min_alignment: int = max(16, align_of(Memory_Block))
+	min_alignment: int = max(16, align_of(Memory_Block), int(alignment))
 	data := mem_alloc(int(total_size), min_alignment, allocator, loc) or_return
 	block = (^Memory_Block)(raw_data(data))
 	end := uintptr(raw_data(data)[len(data):])
@@ -115,7 +115,7 @@ arena_alloc :: proc(arena: ^Arena, size, alignment: uint, loc := #caller_locatio
 			arena.backing_allocator = default_allocator()
 		}
 
-		new_block := memory_block_alloc(arena.backing_allocator, block_size, loc) or_return
+		new_block := memory_block_alloc(arena.backing_allocator, block_size, alignment, loc) or_return
 		new_block.prev = arena.curr_block
 		arena.curr_block = new_block
 		arena.total_capacity += new_block.capacity
@@ -134,7 +134,7 @@ arena_init :: proc(arena: ^Arena, size: uint, backing_allocator: Allocator, loc
 	arena^ = {}
 	arena.backing_allocator = backing_allocator
 	arena.minimum_block_size = max(size, 1<<12) // minimum block size of 4 KiB
-	new_block := memory_block_alloc(arena.backing_allocator, arena.minimum_block_size, loc) or_return
+	new_block := memory_block_alloc(arena.backing_allocator, arena.minimum_block_size, 0, loc) or_return
 	arena.curr_block = new_block
 	arena.total_capacity += new_block.capacity
 	return nil