From 86a48bfea137500c525fabd6ee5bfdfadef3144b Mon Sep 17 00:00:00 2001
From: Ash Wolf <ninji@wuffs.org>
Date: Sat, 14 Jan 2023 13:23:03 +0000
Subject: [PATCH] a little more cleanup

---
 compiler_and_linker/unsorted/Alias.c            | 17 ++++-------------
 .../unsorted/InterferenceGraph.c                | 15 +++++----------
 2 files changed, 9 insertions(+), 23 deletions(-)

diff --git a/compiler_and_linker/unsorted/Alias.c b/compiler_and_linker/unsorted/Alias.c
index b86fb41..8223bf4 100644
--- a/compiler_and_linker/unsorted/Alias.c
+++ b/compiler_and_linker/unsorted/Alias.c
@@ -309,30 +309,24 @@ static int addresspropagatestouse(int candidateID, int useID) {
 
     if (candidate_pcode->block == use_pcode->block && precedes(candidate_pcode, use_pcode)) {
         for (scan = candidate_pcode->nextPCode; scan && scan != use_pcode; scan = scan->nextPCode) {
-            op = scan->args;
-            i = scan->argCount;
-            while (i--) {
+            for (op = scan->args, i = scan->argCount; i--; op++) {
                 if (op->kind == PCOp_REGISTER &&
                     op->arg == RegClass_GPR &&
                     (op->data.reg.effect & EffectWrite) &&
                     op->data.reg.reg == reg)
                     return 1;
-                op++;
             }
         }
     } else {
         if (!bitvectorgetbit(candidateID, propinfo[use_pcode->block->blockIndex].vec8)) {
             if (bitvectorgetbit(candidate_pcode->defID, usedefinfo[use_pcode->block->blockIndex].defvec8)) {
                 for (scan = use_pcode->block->firstPCode; scan && scan != use_pcode; scan = scan->nextPCode) {
-                    op = scan->args;
-                    i = scan->argCount;
-                    while (i--) {
+                    for (op = scan->args, i = scan->argCount; i--; op++) {
                         if (op->kind == PCOp_REGISTER &&
                             op->arg == RegClass_GPR &&
                             (op->data.reg.effect & EffectWrite) &&
                             op->data.reg.reg == reg)
                             return 1;
-                        op++;
                     }
                 }
             } else {
@@ -343,15 +337,12 @@ static int addresspropagatestouse(int candidateID, int useID) {
         for (scan = use_pcode->block->firstPCode; scan; scan = scan->nextPCode) {
             if (scan == use_pcode)
                 break;
-            op = scan->args;
-            i = scan->argCount;
-            while (i--) {
+            for (op = scan->args, i = scan->argCount; i--; op++) {
                 if (op->kind == PCOp_REGISTER &&
                     op->arg == RegClass_GPR &&
                     (op->data.reg.effect & EffectWrite) &&
                     op->data.reg.reg == reg)
                     return 1;
-                op++;
             }
         }
     }
@@ -538,7 +529,7 @@ void gather_alias_info(void) {
                                 if (
                                     (!(pcode->flags & (fIsWrite | fPCodeFlag40000)) || op != pcode->args) &&
                                     op->kind == PCOp_REGISTER &&
-                                    (RegClass) op->arg == RegClass_GPR &&
+                                    op->arg == RegClass_GPR &&
                                     (op->data.reg.effect & EffectRead)
                                     ) {
                                     alias_array[aliases_idx] = NULL;
diff --git a/compiler_and_linker/unsorted/InterferenceGraph.c b/compiler_and_linker/unsorted/InterferenceGraph.c
index 99f4512..d589502 100644
--- a/compiler_and_linker/unsorted/InterferenceGraph.c
+++ b/compiler_and_linker/unsorted/InterferenceGraph.c
@@ -33,16 +33,14 @@ int interferes(UInt32 a, UInt32 b) {
 }
 
 static void buildinterferencematrix(void) {
-    UInt32 regs; // r31
     PCodeBlock *block; // r30
     PCode *instr; // r29
-    UInt32 *vec; // r28
     PCodeArg *op;
-    int reg;
+    UInt32 *vec; // r28
     UInt32 i;
     UInt32 j;
 
-    regs = used_virtual_registers[coloring_class];
+    UInt32 regs = used_virtual_registers[coloring_class];
     interferencematrix = oalloc(4 * ((((regs * regs) / 2) + 31) >> 5));
     bitvectorinitialize(interferencematrix, (regs * regs) / 2, 0);
 
@@ -57,7 +55,7 @@ static void buildinterferencematrix(void) {
         for (instr = block->lastPCode; instr; instr = instr->prevPCode) {
             for (op = instr->args, i = instr->argCount; i--; op++) {
                 if (PC_OP_IS_WRITE_ANY_REGISTER(op, coloring_class)) {
-                    reg = op->data.reg.reg;
+                    int reg = op->data.reg.reg;
                     bitvectorclearbit(reg, vec);
                     for (j = 0; j < regs; j++) {
                         if (bitvectorgetbit(j, vec)) {
@@ -75,7 +73,7 @@ static void buildinterferencematrix(void) {
 
             for (op = instr->args, i = instr->argCount; i--; op++) {
                 if (PC_OP_IS_READ_ANY_REGISTER(op, coloring_class)) {
-                    reg = op->data.reg.reg;
+                    int reg = op->data.reg.reg;
                     if (bitvectorgetbit(op->data.reg.reg, vec) == 0)
                         op->data.reg.effect |= Effect4;
                     bitvectorsetbit(reg, vec);
@@ -124,14 +122,11 @@ static void buildinterferencematrix(void) {
                     CError_ASSERT(226, i <= instr->argCount);
                 }
 
-                op = instr->args + i;
-                while (i < instr->argCount) {
+                for (op = instr->args + i; i < instr->argCount; i++, op++) {
                     if (op->kind == PCOp_REGISTER && op->arg == RegClass_GPR) {
                         for (j = 0; j < n_scratch_registers[coloring_class]; j++)
                             makeinterfere(op->data.reg.reg, scratch_registers[coloring_class][j]);
                     }
-                    i++;
-                    op++;
                 }
             }
         }