1 files changed, 31 insertions, 22 deletions

diff --git a/includes/compiler/PCode.h b/includes/compiler/PCode.h
index f1f786c..b38d9e1 100644
--- a/includes/compiler/PCode.h
+++ b/includes/compiler/PCode.h
@@ -34,19 +34,19 @@ enum {
 
 typedef enum {
     RefType_0,
-    RefType_1,
-    RefType_2,
-    RefType_3,
+    RefType_1, // like D, but 32-bit?
+    RefType_2, // matches MW_RELOC_3?
+    RefType_3, // matches MW_RELOC_4?
     RefType_4,
     RefType_5,
-    RefType_6,
-    RefType_7,
-    RefType_8,
+    RefType_6, // LO16?
+    RefType_7, // HI16?
+    RefType_8, // HA16?
     RefType_9,
-    RefType_A,
-    RefType_B,
-    RefType_C,
-    RefType_D
+    RefType_A, // another LO
+    RefType_B, // another HA
+    RefType_C, // another HA
+    RefType_D // another LO
 } PCRefType;
 
 struct PCodeArg {
@@ -94,6 +94,12 @@ struct PCodeArg {
  (_op)->data.reg.reg == (_reg) &&                   \
  ((_op)->data.reg.effect & EffectWrite))
 
+#define PC_OP_IS_R_OR_W_REGISTER(_op, _rclass, _reg) \
+((_op)->kind == PCOp_REGISTER &&                    \
+ (_op)->arg == (_rclass) &&                         \
+ (_op)->data.reg.reg == (_reg) &&                   \
+ ((_op)->data.reg.effect & (EffectRead | EffectWrite)))
+
 #define PC_OP_IS_ANY_REGISTER(_op, _rclass) \
 ((_op)->kind == PCOp_REGISTER &&            \
  (_op)->arg == (_rclass))
@@ -152,16 +158,16 @@ struct PCodeBlock {
 
 /* PCode Flags */
 enum {
-    fPCodeFlag1 = 1,
-    fPCodeFlag2 = 2, // some kinda load
-    fPCodeFlag4 = 4, // some kinda store
-    fPCodeFlag8 = 8,
-    fPCodeFlag10 = 0x10,
-    fPCodeFlag20 = 0x20,
+    fPCodeFlag1 = 1, // some kinds of branches
+    fPCodeFlag2 = 2, // read from memory
+    fPCodeFlag4 = 4, // write to memory
+    fPCodeFlag8 = 8, // other kinds of branches
+    fPCodeFlag10 = 0x10, // moves
+    fPCodeFlag20 = 0x20, // indexed operations
     // Always valid
     fIsConst = 0x40,
     fIsVolatile = 0x80,
-    fSideEffects = 0x100,
+    fSideEffects = 0x100, // instructions that do weird stuff with PPC state
     fPCodeFlag200 = 0x200, // ?
     fPCodeFlag400 = 0x400, // ?
     fPCodeFlag800 = 0x800, // ?
@@ -171,23 +177,24 @@ enum {
     fPCodeFlag8000 = 0x8000,
     fPCodeFlag20000 = 0x20000, // some kinda load?
     fPCodeFlag40000 = 0x40000, // some kinda store?
-    // Set 1 only
+    // Set 1 (branches) only
     fLink = 0x1000000,
     fBranchNotTaken = 0x4000000,
     fBranchTaken = 0x8000000,
     fAbsolute = 0x10000000,
-    // Set 2 only
+    // Set 2 (non-branches) only
     fIsPtrOp = 0x20,
     fOverflow = 0x800000,
     fSetsCarry = 0x10000000,
+    fPCodeFlag20000000 = 0x20000000, // record bit?
     // ??
     fPCodeFlag2000000 = 0x2000000,
     fPCodeFlag4000000 = 0x4000000,
     fPCodeFlag8000000 = 0x8000000,
     fPCodeFlag10000000 = 0x10000000,
-    fPCodeFlag20000000 = 0x20000000, // record bit?
     fPCodeFlag40000000 = 0x40000000,
-    fPCodeFlag80000000 = 0x80000000
+    fPCodeFlag80000000 = 0x80000000,
+    fPCodeFlagC0000000 = 0xC0000000
 };
 
 enum {
@@ -198,7 +205,9 @@ enum {
     fPCBlockFlag10 = 0x10,
     fPCBlockFlag20 = 0x20,
     fPCBlockFlag2000 = 0x2000,
-    fPCBlockFlag4000 = 0x4000
+    fPCBlockFlag4000 = 0x4000,
+    fPCBlockFlag6000 = 0x6000,
+    fPCBlockFlag8000 = 0x8000
 };
 
 extern PCodeBlock *pcbasicblocks;