SCI: change segment offsets in reg segments to be in half reg_t.

This makes offsets in raw and reg segments consistent, which
fixes string addressing in savegame dialogs.

svn-id: r44396

3 files changed, 5 insertions, 9 deletions

diff --git a/engines/sci/engine/seg_manager.cpp b/engines/sci/engine/seg_manager.cpp
index 942c3f6299..5d81d8ef35 100644
--- a/engines/sci/engine/seg_manager.cpp
+++ b/engines/sci/engine/seg_manager.cpp
@@ -859,9 +859,8 @@ byte *SegManager::derefBulkPtr(reg_t pointer, int entries) {
 }
 
 reg_t *SegManager::derefRegPtr(reg_t pointer, int entries) {
-	const int align = sizeof(reg_t);
-	if (pointer.offset & (align - 1)) {
-		warning("Unaligned pointer read: %04x:%04x expected with %d alignment", PRINT_REG(pointer), align);
+	if (pointer.offset & 1) {
+		warning("Unaligned pointer read: %04x:%04x expected with word alignment", PRINT_REG(pointer));
 		return NULL;
 	}
 
diff --git a/engines/sci/engine/segment.cpp b/engines/sci/engine/segment.cpp
index 793878f7b5..5851ec994a 100644
--- a/engines/sci/engine/segment.cpp
+++ b/engines/sci/engine/segment.cpp
@@ -264,7 +264,7 @@ SegmentRef LocalVariables::dereference(reg_t pointer) {
 	SegmentRef ret;
 	ret.isRaw = false;	// reg_t based data!
 	ret.maxSize = _locals.size() * sizeof(reg_t);
-	ret.raw = (byte *)&_locals[0] + pointer.offset;
+	ret.raw = (byte *)&_locals[pointer.offset/2];
 	return ret;
 }
 
@@ -279,7 +279,7 @@ SegmentRef DataStack::dereference(reg_t pointer) {
 	// FIXME: Is this correct? See comment in LocalVariables::dereference
 	if (pointer.offset & 1)
 		warning("LocalVariables::dereference: Odd offset in pointer  %04x:%04x", PRINT_REG(pointer));
-	ret.raw = (byte *)_entries + pointer.offset;
+	ret.raw = (byte *)&_entries[pointer.offset/2];
 	return ret;
 }
 
diff --git a/engines/sci/engine/vm.cpp b/engines/sci/engine/vm.cpp
index ed20c9fed6..78f2d24a1c 100644
--- a/engines/sci/engine/vm.cpp
+++ b/engines/sci/engine/vm.cpp
@@ -490,9 +490,6 @@ static reg_t pointer_add(EngineState *s, reg_t base, int offset) {
 	switch (mobj->getType()) {
 
 	case SEG_TYPE_LOCALS:
-		base.offset += 2 * offset;
-		return base;
-
 	case SEG_TYPE_SCRIPT:
 	case SEG_TYPE_STACK:
 	case SEG_TYPE_DYNMEM:
@@ -1112,7 +1109,7 @@ void run_vm(EngineState *s, int restoring) {
 				r_temp.offset += signed_validate_arithmetic(s->r_acc);
 
 			r_temp.offset += opparams[1];  // Add index
-			r_temp.offset *= sizeof(reg_t);
+			r_temp.offset *= 2; // variables are 16 bit
 			// That's the immediate address now
 			s->r_acc = r_temp;
 			break;