From d0be6607d103d03677ee4cee297b08edc71edc86 Mon Sep 17 00:00:00 2001
From: Steven Massey <soundandform@gmail.com>
Date: Sun, 2 May 2021 14:52:14 -0700
Subject: [PATCH] null var bug fixes

---
 source/m3_compile.c | 61 +++++++++++++++++++++++++--------------------
 source/m3_compile.h |  2 +-
 2 files changed, 35 insertions(+), 28 deletions(-)

diff --git a/source/m3_compile.c b/source/m3_compile.c
index a867991..280cf54 100644
--- a/source/m3_compile.c
+++ b/source/m3_compile.c
@@ -1114,7 +1114,10 @@ _   (Read_u8 (& opcode, & o->wasm, o->wasmEnd));             m3log (compile, d_i
 
     //printf("Extended opcode: 0x%x\n", i_opcode);
 
-    M3Compiler compiler = GetOpInfo (i_opcode)->compiler;
+	IM3OpInfo opInfo = GetOpInfo (i_opcode);
+	_throwif (m3Err_unknownOpcode, not opInfo);
+
+	M3Compiler compiler = opInfo->compiler;
     _throwif (m3Err_noCompiler, not compiler);
 
 _   ((* compiler) (o, i_opcode));
@@ -1979,9 +1982,10 @@ M3Result  Compile_Operator  (IM3Compilation o, m3opcode_t i_opcode)
 {
     M3Result result;
 
-    const M3OpInfo * op = GetOpInfo(i_opcode);
+    IM3OpInfo opInfo = GetOpInfo (i_opcode);
+	_throwif (m3Err_unknownOpcode, not opInfo);
 
-    IM3Operation operation;
+    IM3Operation op;
 
     // This preserve is for for FP compare operations.
     // either need additional slot destination operations or the
@@ -1989,64 +1993,64 @@ M3Result  Compile_Operator  (IM3Compilation o, m3opcode_t i_opcode)
     // moving out the way might be the optimal solution most often?
     // otherwise, the _r0 reg can get buried down in the stack
     // and be idle & wasted for a moment.
-    if (IsFpType (GetStackTopType (o)) and IsIntType (op->type))
+    if (IsFpType (GetStackTopType (o)) and IsIntType (opInfo->type))
     {
-_       (PreserveRegisterIfOccupied (o, op->type));
+_       (PreserveRegisterIfOccupied (o, opInfo->type));
     }
 
-    if (op->stackOffset == 0)
+    if (opInfo->stackOffset == 0)
     {
         if (IsStackTopInRegister (o))
         {
-            operation = op->operations [0]; // _s
+            op = opInfo->operations [0]; // _s
         }
         else
         {
-_           (PreserveRegisterIfOccupied (o, op->type));
-            operation = op->operations [1]; // _r
+_           (PreserveRegisterIfOccupied (o, opInfo->type));
+            op = opInfo->operations [1]; // _r
         }
     }
     else
     {
         if (IsStackTopInRegister (o))
         {
-            operation = op->operations [0];  // _rs
+            op = opInfo->operations [0];  // _rs
 
             if (IsStackTopMinus1InRegister (o))
             {                                       d_m3Assert (i_opcode == 0x38 or i_opcode == 0x39);
-                operation = op->operations [3]; // _rr for fp.store
+                op = opInfo->operations [3]; // _rr for fp.store
             }
         }
         else if (IsStackTopMinus1InRegister (o))
         {
-            operation = op->operations [1]; // _sr
+            op = opInfo->operations [1]; // _sr
 
-            if (not operation)  // must be commutative, then
-                operation = op->operations [0];
+            if (not op)  // must be commutative, then
+                op = opInfo->operations [0];
         }
         else
         {
-_           (PreserveRegisterIfOccupied (o, op->type));     // _ss
-            operation = op->operations [2];
+_           (PreserveRegisterIfOccupied (o, opInfo->type));     // _ss
+            op = opInfo->operations [2];
         }
     }
 
-    if (operation)
+    if (op)
     {
-_       (EmitOp (o, operation));
+_       (EmitOp (o, op));
 
 _       (EmitSlotNumOfStackTopAndPop (o));
 
-        if (op->stackOffset < 0)
+        if (opInfo->stackOffset < 0)
 _           (EmitSlotNumOfStackTopAndPop (o));
 
-        if (op->type != c_m3Type_none)
-_           (PushRegister (o, op->type));
+        if (opInfo->type != c_m3Type_none)
+_           (PushRegister (o, opInfo->type));
     }
     else
     {
 #       ifdef DEBUG
-            result = ErrorCompile ("no operation found for opcode", o, "'%s'", op->name);
+            result = ErrorCompile ("no operation found for opcode", o, "'%s'", opInfo->name);
 #       else
             result = ErrorCompile ("no operation found for opcode", o, "");
 #       endif
@@ -2061,7 +2065,8 @@ M3Result  Compile_Convert  (IM3Compilation o, m3opcode_t i_opcode)
 {
     M3Result result = m3Err_none;
 
-    const M3OpInfo * opInfo = GetOpInfo(i_opcode);
+    IM3OpInfo opInfo = GetOpInfo (i_opcode);
+	_throwif (m3Err_unknownOpcode, not opInfo);
 
     bool destInSlot = IsRegisterTypeAllocated (o, opInfo->type);
     bool sourceInSlot = IsStackTopInSlot (o);
@@ -2090,9 +2095,10 @@ _try {
 _   (ReadLEB_u32 (& alignHint, & o->wasm, o->wasmEnd));
 _   (ReadLEB_u32 (& memoryOffset, & o->wasm, o->wasmEnd));
                                                                         m3log (compile, d_indent " (offset = %d)", get_indention_string (o), memoryOffset);
-    const M3OpInfo * op = GetOpInfo(i_opcode);
+    IM3OpInfo opInfo = GetOpInfo (i_opcode);
+	_throwif (m3Err_unknownOpcode, not opInfo);
 
-    if (IsFpType (op->type))
+    if (IsFpType (opInfo->type))
 _       (PreserveRegisterIfOccupied (o, c_m3Type_f64));
 
 _   (Compile_Operator (o, i_opcode));
@@ -2389,7 +2395,8 @@ const M3OpInfo c_operationsFC [] =
 # endif
 };
 
-const M3OpInfo*  GetOpInfo  (m3opcode_t opcode)
+
+IM3OpInfo  GetOpInfo  (m3opcode_t opcode)
 {
     switch (opcode >> 8) {
     case 0x00:
@@ -2430,7 +2437,7 @@ _       (Read_opcode (& opcode, & o->wasm, o->wasmEnd));                log_opco
             }
         }
 
-        IM3OpInfo opinfo = GetOpInfo(opcode);
+        IM3OpInfo opinfo = GetOpInfo (opcode);
 		
 		if (opinfo == NULL)
 			_throw (ErrorCompile (m3Err_unknownOpcode, o, "opcode '%x' not available", opcode));
diff --git a/source/m3_compile.h b/source/m3_compile.h
index cca423f..d16e364 100644
--- a/source/m3_compile.h
+++ b/source/m3_compile.h
@@ -137,7 +137,7 @@ M3OpInfo;
 
 typedef const M3OpInfo *    IM3OpInfo;
 
-extern const M3OpInfo* GetOpInfo(m3opcode_t opcode);
+IM3OpInfo  GetOpInfo  (m3opcode_t opcode);
 
 // TODO: This helper should be removed, when MultiValue is implemented
 static inline