From 0f22b1efb9c7f3485e2147911c3e57f75d18fb48 Mon Sep 17 00:00:00 2001
From: Dennis Ranke <dennis.ranke@gmail.com>
Date: Tue, 28 Dec 2021 21:43:58 +0100
Subject: [PATCH] some more loader size optimizations

---
 platform/bin/loader.wasm | Bin 1251 -> 1235 bytes
 platform/src/loader.cwa  |  33 ++++++++++++++-------------------
 2 files changed, 14 insertions(+), 19 deletions(-)

diff --git a/platform/bin/loader.wasm b/platform/bin/loader.wasm
index 5030f0ffec7aa90ab6abe625af78f4a756d4cb3b..ab4860eab482370a4b37670fc5d815f3bfb0e732 100644
GIT binary patch
delta 305
zcmXYrJx;?w5QXQ>+PjK25vxc@l(Q?hbW{<Ar$9nf)H#9;O_bDjN;*(_dTLHUP00~B
z09Rma=;r5r@4fHE*W&pBuP=|E>uXelP=;%T1&Xem?r||x8V)Op^F^o^?&2CSr9hBS
zI62|i(1a=7Rjqwk(HHJa!QCa%hG>Zx;~U@&Y@pPz>79<)&^VsiWN}W9?$)BXb*)nJ
zr8YBEryraTg>P0a>IbJfdqXW-xc~E>t7V9vQoR|}iX2Q76nhED?@G{-Cu^gEwfQHa
g)VW$xv~#=y4~AIxF8L{U9#w1;-n(7K`x9^Z7og58lK=n!

delta 342
zcmXX?J5B>J5cSM>y^5R&*Hq(GL`O-JYNtRTN{-<GQlj*`dxJzA1Br$cP*ZXQ4g$|h
z3QIHA`_A{`XK{R@_tW#2-H{*E8I?@tGUJK#%1YPHb>4p6PUW!AtYU4+qBKL*+eo{W
zi%PFAbU9o(1@*!A;MS409Tz3#0-24&7qBtD5e2xdVYOyJtIEcW;{_%vu$$x_K!%LD
z6uRJhZTw)=*vKhF-`m8gfjk27?MkA3V$VYhF{*ysv)?&pTa&bq1ZOTLMhBG?_MJeo
rnt>%X;Xfm4$juU2mEsNYQ2V4BgXSZppp0wOg-f2BmdwkKi68k7dU!I}

diff --git a/platform/src/loader.cwa b/platform/src/loader.cwa
index 658d5ac..1b1b2f2 100644
--- a/platform/src/loader.cwa
+++ b/platform/src/loader.cwa
@@ -43,17 +43,16 @@ export fn load_uw8(module_size: i32) -> i32 {
 }
 
 fn section_size(ptr: i32) -> i32 {
-    let p = ptr + 1;
-    let l = 0;
-    let shift = 0;
+    let p = ptr;
+    let l: i32;
+    let shift: i32;
     loop size {
-        let lazy b = p?0;
+        let lazy b = (p := p + 1)?0;
         l = l | ((b & 127) << shift);
         shift = shift + 7;
-        p = p + 1;
-        branch_if b & 128: size;
+        branch_if b >> 7: size;
     }
-    p - ptr + l
+    p + 1 - ptr + l
 }
 
 fn copy_section(dest: i32, src: i32) -> i32 {
@@ -63,10 +62,10 @@ fn copy_section(dest: i32, src: i32) -> i32 {
 }
 
 fn copy(dest: i32, src: i32, len: i32) {
-    if len > 0 {
-        loop bytes {
+    loop bytes {
+        if len > 0 {
             (dest + (len := len - 1))?0 = (src + len)?0;
-            branch_if len: bytes
+            branch bytes;
         }
     }
 }
@@ -84,12 +83,10 @@ export fn uncompress(src_ptr: i32, dest_ptr: i32) -> i32 {
 
     let offset: i32;
 
-    let byte: i32;
-
     let i: i32;
     loop init_contexts {
         i?0x3c000 = 0x80;
-        branch_if (i := i + 1) < 256 + 1 + 128: init_contexts
+        branch_if (i := i + 1) < 256 + 1 + 128: init_contexts;
     }
 
     let prev_was_match: i32;
@@ -100,8 +97,7 @@ export fn uncompress(src_ptr: i32, dest_ptr: i32) -> i32 {
             if is_match {
                 let inline new_offset = if prev_was_match { 1 } else { upkr_bit(256) };
                 if new_offset {
-                    offset = upkr_length(257) - 1;
-                    branch_if !offset: finished
+                    branch_if !(offset := upkr_length(257) - 1): finished;
                 }
                 let length = upkr_length(257 + 64);
                 loop copy {
@@ -111,7 +107,7 @@ export fn uncompress(src_ptr: i32, dest_ptr: i32) -> i32 {
                 }
             } else {
                 // literal
-                byte = 1;
+                let byte = 1;
                 loop literal {
                     branch_if (byte := (byte << 1) | upkr_bit(byte)) < 256: literal;
                 }
@@ -130,9 +126,8 @@ fn upkr_length(context_index: i32) -> i32 {
     let length: i32;
     let bit_pos: i32;
     loop bits {
-        if upkr_bit(context_index) {
-            length = length | (upkr_bit(context_index + 1) << bit_pos);
-            context_index = context_index + 2;
+        if upkr_bit(context_index + bit_pos) {
+            length = length | (upkr_bit(context_index + bit_pos + 32) << bit_pos);
             bit_pos = bit_pos + 1;
             branch bits;
         }