From b985cd0ea55ca2b91e7b74bd58ccf9688f393bd1 Mon Sep 17 00:00:00 2001
From: Nikolay Nikolov <nickysn@gmail.com>
Date: Sun, 11 Aug 2024 02:24:02 +0300
Subject: [PATCH] * WebAssembly threads internal linker: implement memory
 initialization in TWasmExeOutput.GenerateCode_InitSharedMemory

---
 compiler/ogwasm.pas | 25 ++++++++++++++++++++++++-
 1 file changed, 24 insertions(+), 1 deletion(-)

diff --git a/compiler/ogwasm.pas b/compiler/ogwasm.pas
index e46fb7f52b..37d078d1d2 100644
--- a/compiler/ogwasm.pas
+++ b/compiler/ogwasm.pas
@@ -5569,6 +5569,9 @@ implementation
         InitFlagOfs=256;
       var
         Sec: TObjSection;
+        DataSecName: string;
+        DataSecIdx: Integer;
+        ExeSec: TExeSection;
       begin
         if not (ts_wasm_threads in current_settings.targetswitches) then
           exit;
@@ -5599,7 +5602,27 @@ implementation
         { end }
         Sec.writeUInt8($0B);
 
-        { TODO: memory.init and memory.fill }
+        DataSecIdx:=-1;
+        for DataSecName in DataSections do
+          begin
+            ExeSec:=FindExeSection(DataSecName);
+            if Assigned(ExeSec) and (ExeSec.Size>0) then
+              begin
+                Inc(DataSecIdx);
+                { i32.const $memPos }
+                Sec.writeUInt8($41);
+                WriteUleb5(sec,ExeSec.MemPos);
+                { i32.const 0 }
+                Sec.writeUInt16BE($4100);
+                { i32.const size }
+                Sec.writeUInt8($41);
+                WriteUleb5(sec,ExeSec.Size);
+                { memory.init $DataSecIdx 0 }
+                Sec.writeUInt16BE($fc08);
+                WriteUleb5(sec,DataSecIdx);
+                Sec.writeUInt8(0);
+              end;
+          end;
 
         { i32.const $InitFlag }
         Sec.writeUInt8($41);