From 81c510336990cb3a4a0efd218aa44af278508606 Mon Sep 17 00:00:00 2001
From: MaxGraey <maxgraey@gmail.com>
Date: Wed, 29 Jul 2020 20:14:56 +0300
Subject: [PATCH] simplify check condision for memcpy

---
 std/assembly/util/memory.ts                   |  2 +-
 .../extends-baseaggregate.untouched.wat       | 19 ++++++++-----------
 tests/compiler/infer-array.untouched.wat      | 19 ++++++++-----------
 tests/compiler/number.untouched.wat           | 19 ++++++++-----------
 tests/compiler/object-literal.untouched.wat   | 19 ++++++++-----------
 tests/compiler/resolve-access.untouched.wat   | 19 ++++++++-----------
 tests/compiler/resolve-binary.untouched.wat   | 19 ++++++++-----------
 .../resolve-elementaccess.untouched.wat       | 19 ++++++++-----------
 tests/compiler/resolve-ternary.untouched.wat  | 19 ++++++++-----------
 .../retain-release-sanity.untouched.wat       | 19 ++++++++-----------
 tests/compiler/rt/finalize.untouched.wat      | 19 ++++++++-----------
 tests/compiler/rt/stub-realloc.untouched.wat  | 19 ++++++++-----------
 .../compiler/std/array-literal.untouched.wat  | 19 ++++++++-----------
 tests/compiler/std/array.untouched.wat        | 19 ++++++++-----------
 tests/compiler/std/arraybuffer.untouched.wat  | 19 ++++++++-----------
 tests/compiler/std/map.untouched.wat          | 19 ++++++++-----------
 tests/compiler/std/pointer.untouched.wat      | 19 ++++++++-----------
 tests/compiler/std/set.untouched.wat          | 19 ++++++++-----------
 tests/compiler/std/static-array.untouched.wat | 19 ++++++++-----------
 tests/compiler/std/staticarray.untouched.wat  | 19 ++++++++-----------
 .../std/string-casemapping.untouched.wat      | 19 ++++++++-----------
 .../std/string-encoding.untouched.wat         | 19 ++++++++-----------
 tests/compiler/std/string.untouched.wat       | 19 ++++++++-----------
 tests/compiler/std/symbol.untouched.wat       | 19 ++++++++-----------
 tests/compiler/std/typedarray.untouched.wat   | 19 ++++++++-----------
 tests/compiler/wasi/trace.untouched.wat       | 19 ++++++++-----------
 26 files changed, 201 insertions(+), 276 deletions(-)

diff --git a/std/assembly/util/memory.ts b/std/assembly/util/memory.ts
index d5daa5f526..07a9bb98dd 100644
--- a/std/assembly/util/memory.ts
+++ b/std/assembly/util/memory.ts
@@ -146,7 +146,7 @@ export function memcpy(dest: usize, src: usize, n: usize): void { // see: musl/s
 export function memmove(dest: usize, src: usize, n: usize): void { // see: musl/src/string/memmove.c
   if (dest === src) return;
   if (ASC_SHRINK_LEVEL < 1) {
-    if (src + n <= dest || dest + n <= src) {
+    if (src - dest - n <= -(n << 1)) {
       memcpy(dest, src, n);
       return;
     }
diff --git a/tests/compiler/extends-baseaggregate.untouched.wat b/tests/compiler/extends-baseaggregate.untouched.wat
index a940f6a811..664c7a63fa 100644
--- a/tests/compiler/extends-baseaggregate.untouched.wat
+++ b/tests/compiler/extends-baseaggregate.untouched.wat
@@ -2658,19 +2658,16 @@
    i32.lt_s
    drop
    local.get $4
-   local.get $3
-   i32.add
    local.get $5
+   i32.sub
+   local.get $3
+   i32.sub
+   i32.const 0
+   local.get $3
+   i32.const 1
+   i32.shl
+   i32.sub
    i32.le_u
-   if (result i32)
-    i32.const 1
-   else
-    local.get $5
-    local.get $3
-    i32.add
-    local.get $4
-    i32.le_u
-   end
    if
     local.get $5
     local.get $4
diff --git a/tests/compiler/infer-array.untouched.wat b/tests/compiler/infer-array.untouched.wat
index 9ccbfba964..6ee473ce24 100644
--- a/tests/compiler/infer-array.untouched.wat
+++ b/tests/compiler/infer-array.untouched.wat
@@ -1192,19 +1192,16 @@
    i32.lt_s
    drop
    local.get $4
-   local.get $3
-   i32.add
    local.get $5
+   i32.sub
+   local.get $3
+   i32.sub
+   i32.const 0
+   local.get $3
+   i32.const 1
+   i32.shl
+   i32.sub
    i32.le_u
-   if (result i32)
-    i32.const 1
-   else
-    local.get $5
-    local.get $3
-    i32.add
-    local.get $4
-    i32.le_u
-   end
    if
     local.get $5
     local.get $4
diff --git a/tests/compiler/number.untouched.wat b/tests/compiler/number.untouched.wat
index 65f30e910c..1075677abd 100644
--- a/tests/compiler/number.untouched.wat
+++ b/tests/compiler/number.untouched.wat
@@ -2498,19 +2498,16 @@
    i32.lt_s
    drop
    local.get $4
-   local.get $3
-   i32.add
    local.get $5
+   i32.sub
+   local.get $3
+   i32.sub
+   i32.const 0
+   local.get $3
+   i32.const 1
+   i32.shl
+   i32.sub
    i32.le_u
-   if (result i32)
-    i32.const 1
-   else
-    local.get $5
-    local.get $3
-    i32.add
-    local.get $4
-    i32.le_u
-   end
    if
     local.get $5
     local.get $4
diff --git a/tests/compiler/object-literal.untouched.wat b/tests/compiler/object-literal.untouched.wat
index b44360f445..770147500f 100644
--- a/tests/compiler/object-literal.untouched.wat
+++ b/tests/compiler/object-literal.untouched.wat
@@ -2845,19 +2845,16 @@
    i32.lt_s
    drop
    local.get $4
-   local.get $3
-   i32.add
    local.get $5
+   i32.sub
+   local.get $3
+   i32.sub
+   i32.const 0
+   local.get $3
+   i32.const 1
+   i32.shl
+   i32.sub
    i32.le_u
-   if (result i32)
-    i32.const 1
-   else
-    local.get $5
-    local.get $3
-    i32.add
-    local.get $4
-    i32.le_u
-   end
    if
     local.get $5
     local.get $4
diff --git a/tests/compiler/resolve-access.untouched.wat b/tests/compiler/resolve-access.untouched.wat
index 5380fd4154..9de1f9f8f9 100644
--- a/tests/compiler/resolve-access.untouched.wat
+++ b/tests/compiler/resolve-access.untouched.wat
@@ -1192,19 +1192,16 @@
    i32.lt_s
    drop
    local.get $4
-   local.get $3
-   i32.add
    local.get $5
+   i32.sub
+   local.get $3
+   i32.sub
+   i32.const 0
+   local.get $3
+   i32.const 1
+   i32.shl
+   i32.sub
    i32.le_u
-   if (result i32)
-    i32.const 1
-   else
-    local.get $5
-    local.get $3
-    i32.add
-    local.get $4
-    i32.le_u
-   end
    if
     local.get $5
     local.get $4
diff --git a/tests/compiler/resolve-binary.untouched.wat b/tests/compiler/resolve-binary.untouched.wat
index 60a3172749..586dfd71b8 100644
--- a/tests/compiler/resolve-binary.untouched.wat
+++ b/tests/compiler/resolve-binary.untouched.wat
@@ -3498,19 +3498,16 @@
    i32.lt_s
    drop
    local.get $4
-   local.get $3
-   i32.add
    local.get $5
+   i32.sub
+   local.get $3
+   i32.sub
+   i32.const 0
+   local.get $3
+   i32.const 1
+   i32.shl
+   i32.sub
    i32.le_u
-   if (result i32)
-    i32.const 1
-   else
-    local.get $5
-    local.get $3
-    i32.add
-    local.get $4
-    i32.le_u
-   end
    if
     local.get $5
     local.get $4
diff --git a/tests/compiler/resolve-elementaccess.untouched.wat b/tests/compiler/resolve-elementaccess.untouched.wat
index 3faf9ef489..cd750819a0 100644
--- a/tests/compiler/resolve-elementaccess.untouched.wat
+++ b/tests/compiler/resolve-elementaccess.untouched.wat
@@ -2126,19 +2126,16 @@
    i32.lt_s
    drop
    local.get $4
-   local.get $3
-   i32.add
    local.get $5
+   i32.sub
+   local.get $3
+   i32.sub
+   i32.const 0
+   local.get $3
+   i32.const 1
+   i32.shl
+   i32.sub
    i32.le_u
-   if (result i32)
-    i32.const 1
-   else
-    local.get $5
-    local.get $3
-    i32.add
-    local.get $4
-    i32.le_u
-   end
    if
     local.get $5
     local.get $4
diff --git a/tests/compiler/resolve-ternary.untouched.wat b/tests/compiler/resolve-ternary.untouched.wat
index 8e7fc1c78c..6ad2258385 100644
--- a/tests/compiler/resolve-ternary.untouched.wat
+++ b/tests/compiler/resolve-ternary.untouched.wat
@@ -3889,19 +3889,16 @@
    i32.lt_s
    drop
    local.get $4
-   local.get $3
-   i32.add
    local.get $5
+   i32.sub
+   local.get $3
+   i32.sub
+   i32.const 0
+   local.get $3
+   i32.const 1
+   i32.shl
+   i32.sub
    i32.le_u
-   if (result i32)
-    i32.const 1
-   else
-    local.get $5
-    local.get $3
-    i32.add
-    local.get $4
-    i32.le_u
-   end
    if
     local.get $5
     local.get $4
diff --git a/tests/compiler/retain-release-sanity.untouched.wat b/tests/compiler/retain-release-sanity.untouched.wat
index 3485935621..917fefc811 100644
--- a/tests/compiler/retain-release-sanity.untouched.wat
+++ b/tests/compiler/retain-release-sanity.untouched.wat
@@ -2935,19 +2935,16 @@
    i32.lt_s
    drop
    local.get $4
-   local.get $3
-   i32.add
    local.get $5
+   i32.sub
+   local.get $3
+   i32.sub
+   i32.const 0
+   local.get $3
+   i32.const 1
+   i32.shl
+   i32.sub
    i32.le_u
-   if (result i32)
-    i32.const 1
-   else
-    local.get $5
-    local.get $3
-    i32.add
-    local.get $4
-    i32.le_u
-   end
    if
     local.get $5
     local.get $4
diff --git a/tests/compiler/rt/finalize.untouched.wat b/tests/compiler/rt/finalize.untouched.wat
index ffe4f20ee7..5819deea71 100644
--- a/tests/compiler/rt/finalize.untouched.wat
+++ b/tests/compiler/rt/finalize.untouched.wat
@@ -3278,19 +3278,16 @@
    i32.lt_s
    drop
    local.get $4
-   local.get $3
-   i32.add
    local.get $5
+   i32.sub
+   local.get $3
+   i32.sub
+   i32.const 0
+   local.get $3
+   i32.const 1
+   i32.shl
+   i32.sub
    i32.le_u
-   if (result i32)
-    i32.const 1
-   else
-    local.get $5
-    local.get $3
-    i32.add
-    local.get $4
-    i32.le_u
-   end
    if
     local.get $5
     local.get $4
diff --git a/tests/compiler/rt/stub-realloc.untouched.wat b/tests/compiler/rt/stub-realloc.untouched.wat
index 2fd94b553b..081fb46313 100644
--- a/tests/compiler/rt/stub-realloc.untouched.wat
+++ b/tests/compiler/rt/stub-realloc.untouched.wat
@@ -1198,19 +1198,16 @@
    i32.lt_s
    drop
    local.get $4
-   local.get $3
-   i32.add
    local.get $5
+   i32.sub
+   local.get $3
+   i32.sub
+   i32.const 0
+   local.get $3
+   i32.const 1
+   i32.shl
+   i32.sub
    i32.le_u
-   if (result i32)
-    i32.const 1
-   else
-    local.get $5
-    local.get $3
-    i32.add
-    local.get $4
-    i32.le_u
-   end
    if
     local.get $5
     local.get $4
diff --git a/tests/compiler/std/array-literal.untouched.wat b/tests/compiler/std/array-literal.untouched.wat
index 9f2be3362a..3e64393f57 100644
--- a/tests/compiler/std/array-literal.untouched.wat
+++ b/tests/compiler/std/array-literal.untouched.wat
@@ -2590,19 +2590,16 @@
    i32.lt_s
    drop
    local.get $4
-   local.get $3
-   i32.add
    local.get $5
+   i32.sub
+   local.get $3
+   i32.sub
+   i32.const 0
+   local.get $3
+   i32.const 1
+   i32.shl
+   i32.sub
    i32.le_u
-   if (result i32)
-    i32.const 1
-   else
-    local.get $5
-    local.get $3
-    i32.add
-    local.get $4
-    i32.le_u
-   end
    if
     local.get $5
     local.get $4
diff --git a/tests/compiler/std/array.untouched.wat b/tests/compiler/std/array.untouched.wat
index 6386143d5e..ef9f2c9e29 100644
--- a/tests/compiler/std/array.untouched.wat
+++ b/tests/compiler/std/array.untouched.wat
@@ -3447,19 +3447,16 @@
    i32.lt_s
    drop
    local.get $4
-   local.get $3
-   i32.add
    local.get $5
+   i32.sub
+   local.get $3
+   i32.sub
+   i32.const 0
+   local.get $3
+   i32.const 1
+   i32.shl
+   i32.sub
    i32.le_u
-   if (result i32)
-    i32.const 1
-   else
-    local.get $5
-    local.get $3
-    i32.add
-    local.get $4
-    i32.le_u
-   end
    if
     local.get $5
     local.get $4
diff --git a/tests/compiler/std/arraybuffer.untouched.wat b/tests/compiler/std/arraybuffer.untouched.wat
index eaf6cef877..36a60407d6 100644
--- a/tests/compiler/std/arraybuffer.untouched.wat
+++ b/tests/compiler/std/arraybuffer.untouched.wat
@@ -2833,19 +2833,16 @@
    i32.lt_s
    drop
    local.get $4
-   local.get $3
-   i32.add
    local.get $5
+   i32.sub
+   local.get $3
+   i32.sub
+   i32.const 0
+   local.get $3
+   i32.const 1
+   i32.shl
+   i32.sub
    i32.le_u
-   if (result i32)
-    i32.const 1
-   else
-    local.get $5
-    local.get $3
-    i32.add
-    local.get $4
-    i32.le_u
-   end
    if
     local.get $5
     local.get $4
diff --git a/tests/compiler/std/map.untouched.wat b/tests/compiler/std/map.untouched.wat
index 00c57c04ef..0d84e733ec 100644
--- a/tests/compiler/std/map.untouched.wat
+++ b/tests/compiler/std/map.untouched.wat
@@ -3433,19 +3433,16 @@
    i32.lt_s
    drop
    local.get $4
-   local.get $3
-   i32.add
    local.get $5
+   i32.sub
+   local.get $3
+   i32.sub
+   i32.const 0
+   local.get $3
+   i32.const 1
+   i32.shl
+   i32.sub
    i32.le_u
-   if (result i32)
-    i32.const 1
-   else
-    local.get $5
-    local.get $3
-    i32.add
-    local.get $4
-    i32.le_u
-   end
    if
     local.get $5
     local.get $4
diff --git a/tests/compiler/std/pointer.untouched.wat b/tests/compiler/std/pointer.untouched.wat
index 0ca39c67e8..7a407a2b77 100644
--- a/tests/compiler/std/pointer.untouched.wat
+++ b/tests/compiler/std/pointer.untouched.wat
@@ -1280,19 +1280,16 @@
    i32.lt_s
    drop
    local.get $4
-   local.get $3
-   i32.add
    local.get $5
+   i32.sub
+   local.get $3
+   i32.sub
+   i32.const 0
+   local.get $3
+   i32.const 1
+   i32.shl
+   i32.sub
    i32.le_u
-   if (result i32)
-    i32.const 1
-   else
-    local.get $5
-    local.get $3
-    i32.add
-    local.get $4
-    i32.le_u
-   end
    if
     local.get $5
     local.get $4
diff --git a/tests/compiler/std/set.untouched.wat b/tests/compiler/std/set.untouched.wat
index 81665a6010..b867f31859 100644
--- a/tests/compiler/std/set.untouched.wat
+++ b/tests/compiler/std/set.untouched.wat
@@ -3369,19 +3369,16 @@
    i32.lt_s
    drop
    local.get $4
-   local.get $3
-   i32.add
    local.get $5
+   i32.sub
+   local.get $3
+   i32.sub
+   i32.const 0
+   local.get $3
+   i32.const 1
+   i32.shl
+   i32.sub
    i32.le_u
-   if (result i32)
-    i32.const 1
-   else
-    local.get $5
-    local.get $3
-    i32.add
-    local.get $4
-    i32.le_u
-   end
    if
     local.get $5
     local.get $4
diff --git a/tests/compiler/std/static-array.untouched.wat b/tests/compiler/std/static-array.untouched.wat
index 8f6a22bd54..40be734cf3 100644
--- a/tests/compiler/std/static-array.untouched.wat
+++ b/tests/compiler/std/static-array.untouched.wat
@@ -1229,19 +1229,16 @@
    i32.lt_s
    drop
    local.get $4
-   local.get $3
-   i32.add
    local.get $5
+   i32.sub
+   local.get $3
+   i32.sub
+   i32.const 0
+   local.get $3
+   i32.const 1
+   i32.shl
+   i32.sub
    i32.le_u
-   if (result i32)
-    i32.const 1
-   else
-    local.get $5
-    local.get $3
-    i32.add
-    local.get $4
-    i32.le_u
-   end
    if
     local.get $5
     local.get $4
diff --git a/tests/compiler/std/staticarray.untouched.wat b/tests/compiler/std/staticarray.untouched.wat
index fb7345a2bf..e7b042d83b 100644
--- a/tests/compiler/std/staticarray.untouched.wat
+++ b/tests/compiler/std/staticarray.untouched.wat
@@ -2580,19 +2580,16 @@
    i32.lt_s
    drop
    local.get $4
-   local.get $3
-   i32.add
    local.get $5
+   i32.sub
+   local.get $3
+   i32.sub
+   i32.const 0
+   local.get $3
+   i32.const 1
+   i32.shl
+   i32.sub
    i32.le_u
-   if (result i32)
-    i32.const 1
-   else
-    local.get $5
-    local.get $3
-    i32.add
-    local.get $4
-    i32.le_u
-   end
    if
     local.get $5
     local.get $4
diff --git a/tests/compiler/std/string-casemapping.untouched.wat b/tests/compiler/std/string-casemapping.untouched.wat
index b05241b5eb..3980377e45 100644
--- a/tests/compiler/std/string-casemapping.untouched.wat
+++ b/tests/compiler/std/string-casemapping.untouched.wat
@@ -3005,19 +3005,16 @@
    i32.lt_s
    drop
    local.get $4
-   local.get $3
-   i32.add
    local.get $5
+   i32.sub
+   local.get $3
+   i32.sub
+   i32.const 0
+   local.get $3
+   i32.const 1
+   i32.shl
+   i32.sub
    i32.le_u
-   if (result i32)
-    i32.const 1
-   else
-    local.get $5
-    local.get $3
-    i32.add
-    local.get $4
-    i32.le_u
-   end
    if
     local.get $5
     local.get $4
diff --git a/tests/compiler/std/string-encoding.untouched.wat b/tests/compiler/std/string-encoding.untouched.wat
index 7890591f9c..1fe5cf554d 100644
--- a/tests/compiler/std/string-encoding.untouched.wat
+++ b/tests/compiler/std/string-encoding.untouched.wat
@@ -2632,19 +2632,16 @@
    i32.lt_s
    drop
    local.get $4
-   local.get $3
-   i32.add
    local.get $5
+   i32.sub
+   local.get $3
+   i32.sub
+   i32.const 0
+   local.get $3
+   i32.const 1
+   i32.shl
+   i32.sub
    i32.le_u
-   if (result i32)
-    i32.const 1
-   else
-    local.get $5
-    local.get $3
-    i32.add
-    local.get $4
-    i32.le_u
-   end
    if
     local.get $5
     local.get $4
diff --git a/tests/compiler/std/string.untouched.wat b/tests/compiler/std/string.untouched.wat
index 41b46155f4..f5b19d53cf 100644
--- a/tests/compiler/std/string.untouched.wat
+++ b/tests/compiler/std/string.untouched.wat
@@ -3635,19 +3635,16 @@
    i32.lt_s
    drop
    local.get $4
-   local.get $3
-   i32.add
    local.get $5
+   i32.sub
+   local.get $3
+   i32.sub
+   i32.const 0
+   local.get $3
+   i32.const 1
+   i32.shl
+   i32.sub
    i32.le_u
-   if (result i32)
-    i32.const 1
-   else
-    local.get $5
-    local.get $3
-    i32.add
-    local.get $4
-    i32.le_u
-   end
    if
     local.get $5
     local.get $4
diff --git a/tests/compiler/std/symbol.untouched.wat b/tests/compiler/std/symbol.untouched.wat
index b4b86bb03e..a5bff270c4 100644
--- a/tests/compiler/std/symbol.untouched.wat
+++ b/tests/compiler/std/symbol.untouched.wat
@@ -2817,19 +2817,16 @@
    i32.lt_s
    drop
    local.get $4
-   local.get $3
-   i32.add
    local.get $5
+   i32.sub
+   local.get $3
+   i32.sub
+   i32.const 0
+   local.get $3
+   i32.const 1
+   i32.shl
+   i32.sub
    i32.le_u
-   if (result i32)
-    i32.const 1
-   else
-    local.get $5
-    local.get $3
-    i32.add
-    local.get $4
-    i32.le_u
-   end
    if
     local.get $5
     local.get $4
diff --git a/tests/compiler/std/typedarray.untouched.wat b/tests/compiler/std/typedarray.untouched.wat
index 866450965c..6c73fd6d49 100644
--- a/tests/compiler/std/typedarray.untouched.wat
+++ b/tests/compiler/std/typedarray.untouched.wat
@@ -5083,19 +5083,16 @@
    i32.lt_s
    drop
    local.get $4
-   local.get $3
-   i32.add
    local.get $5
+   i32.sub
+   local.get $3
+   i32.sub
+   i32.const 0
+   local.get $3
+   i32.const 1
+   i32.shl
+   i32.sub
    i32.le_u
-   if (result i32)
-    i32.const 1
-   else
-    local.get $5
-    local.get $3
-    i32.add
-    local.get $4
-    i32.le_u
-   end
    if
     local.get $5
     local.get $4
diff --git a/tests/compiler/wasi/trace.untouched.wat b/tests/compiler/wasi/trace.untouched.wat
index 3491b560ec..78bd45543a 100644
--- a/tests/compiler/wasi/trace.untouched.wat
+++ b/tests/compiler/wasi/trace.untouched.wat
@@ -2086,19 +2086,16 @@
    i32.lt_s
    drop
    local.get $4
-   local.get $3
-   i32.add
    local.get $5
+   i32.sub
+   local.get $3
+   i32.sub
+   i32.const 0
+   local.get $3
+   i32.const 1
+   i32.shl
+   i32.sub
    i32.le_u
-   if (result i32)
-    i32.const 1
-   else
-    local.get $5
-    local.get $3
-    i32.add
-    local.get $4
-    i32.le_u
-   end
    if
     local.get $5
     local.get $4