Optimize WASM arguments and returns (#6181)

Use LLVM arguments and returns where possible (no GC references) instead of passing them on the shadow stack. The argument optimization saves 3% optimized (5% compressed). The return change adds about 0.5% to the uncompressed file, but saves about 6% compressed. They both save size in debug. This also greatly simplifies debugging and reading code. Also includes a fix to the class constructor runner where it was calling cctors with the wrong signature and some test fixes.

1 files changed, 19 insertions, 0 deletions

diff --git a/src/ILCompiler.Compiler/src/Compiler/CompilerTypeSystemContext.Mangling.cs b/src/ILCompiler.Compiler/src/Compiler/CompilerTypeSystemContext.Mangling.cs
index 720f06114..ace374f04 100644
--- a/src/ILCompiler.Compiler/src/Compiler/CompilerTypeSystemContext.Mangling.cs
+++ b/src/ILCompiler.Compiler/src/Compiler/CompilerTypeSystemContext.Mangling.cs
@@ -47,5 +47,24 @@ namespace ILCompiler
                 }
             }
         }
+
+        partial class UnboxingThunk : IPrefixMangledMethod
+        {
+            MethodDesc IPrefixMangledMethod.BaseMethod
+            {
+                get
+                {
+                    return _targetMethod;
+                }
+            }
+
+            string IPrefixMangledMethod.Prefix
+            {
+                get
+                {
+                    return "unbox";
+                }
+            }
+        }
     }
 }