From eec4ed45d12fb5dfc03202b78a362f7b2dd1699d Mon Sep 17 00:00:00 2001
From: drmortalwombat <90205530+drmortalwombat@users.noreply.github.com>
Date: Mon, 20 Nov 2023 22:53:12 +0100
Subject: [PATCH] Fix global array aliasing error

---
 include/fixmath.c               | 30 +++++++++++++++++++++---------
 oscar64/InterCode.cpp           |  2 +-
 oscar64/InterCodeGenerator.cpp  |  2 +-
 oscar64/NativeCodeGenerator.cpp | 14 ++++++++++++++
 4 files changed, 37 insertions(+), 11 deletions(-)

diff --git a/include/fixmath.c b/include/fixmath.c
index 7503a8d..70cf017 100644
--- a/include/fixmath.c
+++ b/include/fixmath.c
@@ -630,19 +630,31 @@ unsigned long lmul16f16(unsigned long x, unsigned long y)
 
 __native long lmul16f16s(long x, long y)
 {
-	if (x < 0)
+	unsigned lox = x;
+	int hix = x >> 16;
+	unsigned loy = y;
+	int hiy = y >> 16;
+
+	long	r = (long)(hix * hiy) << 16;
+
+	if (lox)
 	{
-		if (y < 0)
-			return lmul16f16(-x, -y);
-		else
-			return -lmul16f16(-x, y);
+		r += lmul16u(lox, hiy);
+		if (hiy < 0)
+			r -= (unsigned long)lox << 16;
 	}
-	else if (y < 0)
+	if (loy)
 	{
-		return -lmul16f16(x, -y);
+		r += lmul16u(loy, hix);
+		if (hix < 0)
+			r -= (unsigned long)loy << 16;
 	}
-	else
-		return lmul16f16(x, y);
+	if (lox && loy)
+	{
+		r += lmul16u(lox, loy) >> 16;
+	}
+
+	return r;
 }
 
 __native unsigned long ldiv16f16(unsigned long x, unsigned long y)
diff --git a/oscar64/InterCode.cpp b/oscar64/InterCode.cpp
index 51509e9..c5503f1 100644
--- a/oscar64/InterCode.cpp
+++ b/oscar64/InterCode.cpp
@@ -18594,7 +18594,7 @@ void InterCodeProcedure::Close(void)
 {
 	GrowingTypeArray	tstack(IT_NONE);
 
-	CheckFunc = !strcmp(mIdent->mString, "test");
+	CheckFunc = !strcmp(mIdent->mString, "interpret_expression");
 	CheckCase = false;
 
 	mEntryBlock = mBlocks[0];
diff --git a/oscar64/InterCodeGenerator.cpp b/oscar64/InterCodeGenerator.cpp
index 173c371..43afdbe 100644
--- a/oscar64/InterCodeGenerator.cpp
+++ b/oscar64/InterCodeGenerator.cpp
@@ -686,7 +686,7 @@ void InterCodeGenerator::InitGlobalVariable(InterCodeModule * mod, Declaration*
 		var->mDeclaration = dec;
 		mod->mGlobalVars.Push(var);
 
-		if (dec->mFlags & DTF_VAR_ALIASING)
+		if ((dec->mFlags & DTF_VAR_ALIASING) || (dec->mBase->mType == DT_TYPE_ARRAY && !(type->mFlags & DTF_CONST)))
 			var->mAliased = true;
 
 		dec->mVarIndex = var->mIndex;
diff --git a/oscar64/NativeCodeGenerator.cpp b/oscar64/NativeCodeGenerator.cpp
index f74c204..194253d 100644
--- a/oscar64/NativeCodeGenerator.cpp
+++ b/oscar64/NativeCodeGenerator.cpp
@@ -40431,6 +40431,20 @@ bool NativeCodeBasicBlock::PeepHoleOptimizer(NativeCodeProcedure* proc, int pass
 						else
 							mIns[i + 4].mType = ASMIT_NOP;
 
+						progress = true;
+					}
+					else if (
+						mIns[i + 0].mType == ASMIT_LDA &&
+						mIns[i + 1].mType == ASMIT_STA &&
+						mIns[i + 2].mType == ASMIT_CLC &&
+						mIns[i + 3].mType == ASMIT_ADC && mIns[i + 3].mMode == ASMIM_IMMEDIATE && mIns[i + 3].mAddress == 1 &&
+						mIns[i + 4].mType == ASMIT_STA && mIns[i + 4].SameEffectiveAddress(mIns[i + 0]) && !(mIns[i + 4].mLive & (LIVE_CPU_REG_A | LIVE_CPU_REG_C)) &&
+						HasAsmInstructionMode(ASMIT_INC, mIns[i + 0].mMode))
+					{
+						mIns[i + 4].mType = ASMIT_INC;
+						mIns[i + 2].mType = ASMIT_NOP; mIns[i + 3].mMode = ASMIM_IMPLIED;
+						mIns[i + 3].mType = ASMIT_NOP; mIns[i + 3].mMode = ASMIM_IMPLIED;
+
 						progress = true;
 					}
 #endif