Handle writes to immutable and partly immutable registers.

rizinorg · Nov 11, 2023 · 33a05ca · 33a05ca
1 parent 8f3b134
commit 33a05ca
Showing 1 changed file with 35 additions and 16 deletions.
diff --git a/handwritten/hexagon_il_c/functions.c b/handwritten/hexagon_il_c/functions.c
@@ -467,11 +467,15 @@ static void log_reg_write(RZ_BORROW HexInsnPktBundle *bundle, ut8 reg_num, HexRe
 		pkt->il_op_stats.gpr_written |= (1 << reg_num);
 		break;
 	case HEX_REG_CLASS_CTR_REGS64:
-		pkt->il_op_stats.ctr_written |= (1 << (reg_num + 1));
+		if (hex_ctr_immut_masks[reg_num + 1] != HEX_IMMUTABLE_MASK) {
+			pkt->il_op_stats.ctr_written |= (1 << (reg_num + 1));
+		}
 		// fallthrough
 	case HEX_REG_CLASS_MOD_REGS:
 	case HEX_REG_CLASS_CTR_REGS:
-		pkt->il_op_stats.ctr_written |= (1 << reg_num);
+		if (hex_ctr_immut_masks[reg_num] != HEX_IMMUTABLE_MASK) {
+			pkt->il_op_stats.ctr_written |= (1 << reg_num);
+		}
 		break;
 	case HEX_REG_CLASS_PRED_REGS:
 		pkt->il_op_stats.pred_written |= (1 << reg_num);
@@ -509,6 +513,12 @@ static bool other_slot_wrote_to_pred(const HexInsnPktBundle *bundle, ut32 pred_n
 	return (pw != 0) && slot_w;
 }
 
+static inline RzILOpPure *get_masked_reg_val(RzILOpPure *reg_val, RzILOpPure *val, ut32 mask) {
+	RzILOpPure *masked_val = LOGAND(val, LOGNOT(U32(mask)));
+	RzILOpPure *masked_reg = LOGAND(reg_val, U32(mask));
+	return LOGOR(masked_reg, masked_val);
+}
+
 /**
  * \brief Writes the given value to the register specified in \p op and logs the write.
  * If the register is a double register, each of its sub-registers are written separately.
@@ -528,7 +538,7 @@ RZ_IPI RZ_OWN RzILOpEffect *hex_write_reg(RZ_BORROW HexInsnPktBundle *bundle, co
 	RzILOpPure *high_val = NULL;
 	RzILOpPure *low_val = NULL;
 	ut32 reg_num = hex_resolve_reg_enum_id(op->class, op->op.reg);
-	ut32 dest_width = 0;
+	ut32 dest_width = HEX_GPR_WIDTH;
 	switch (op->class) {
 	default:
 		rz_warn_if_reached();
@@ -544,17 +554,25 @@ RZ_IPI RZ_OWN RzILOpEffect *hex_write_reg(RZ_BORROW HexInsnPktBundle *bundle, co
 	case HEX_REG_CLASS_GENERAL_SUB_REGS:
 		low_name = hex_get_reg_in_class(HEX_REG_CLASS_INT_REGS, reg_num, false, true, true);
 		low_val = CAST(HEX_GPR_WIDTH, IL_FALSE, val);
-		dest_width = HEX_GPR_WIDTH;
 		break;
 	case HEX_REG_CLASS_CTR_REGS64:
-		high_name = hex_get_reg_in_class(HEX_REG_CLASS_CTR_REGS, reg_num + 1, false, true, true);
-		high_val = SHIFTR0(DUP(val), U8(HEX_GPR_WIDTH));
+		if (hex_ctr_immut_masks[reg_num + 1] != HEX_IMMUTABLE_MASK) {
+			high_name = hex_get_reg_in_class(HEX_REG_CLASS_CTR_REGS, reg_num + 1, false, true, true);
+			high_val = SHIFTR0(DUP(val), U8(HEX_GPR_WIDTH));
+			if (hex_ctr_immut_masks[reg_num + 1] != 0) {
+				high_val = get_masked_reg_val(VARG(high_name), CAST(HEX_GPR_WIDTH, IL_FALSE, high_val), hex_ctr_immut_masks[reg_num + 1]);
+			}
+		}
 		// fallthrough
 	case HEX_REG_CLASS_MOD_REGS:
 	case HEX_REG_CLASS_CTR_REGS:
-		low_name = hex_get_reg_in_class(HEX_REG_CLASS_CTR_REGS, reg_num, false, true, true);
-		low_val = CAST(HEX_GPR_WIDTH, IL_FALSE, val);
-		dest_width = HEX_GPR_WIDTH;
+		if (hex_ctr_immut_masks[reg_num] != HEX_IMMUTABLE_MASK) {
+			low_name = hex_get_reg_in_class(HEX_REG_CLASS_CTR_REGS, reg_num, false, true, true);
+			low_val = CAST(HEX_GPR_WIDTH, IL_FALSE, val);
+			if (hex_ctr_immut_masks[reg_num] != 0) {
+				low_val = get_masked_reg_val(VARG(low_name), low_val, hex_ctr_immut_masks[reg_num]);
+			}
+		}
 		break;
 	case HEX_REG_CLASS_PRED_REGS:
 		low_name = hex_get_reg_in_class(HEX_REG_CLASS_PRED_REGS, reg_num, false, true, true);
@@ -567,17 +585,18 @@ RZ_IPI RZ_OWN RzILOpEffect *hex_write_reg(RZ_BORROW HexInsnPktBundle *bundle, co
 		dest_width = HEX_PRED_WIDTH;
 		break;
 	}
-	if (!low_val || dest_width == 0) {
-		rz_warn_if_reached();
-		return NULL;
-	}
 	RzILOpEffect *write_high = high_val ? SETG(high_name, CAST(dest_width, IL_FALSE, high_val)) : NULL;
-	RzILOpEffect *write_low = SETG(low_name, CAST(dest_width, IL_FALSE, low_val));
+	RzILOpEffect *write_low = low_val ? SETG(low_name, CAST(dest_width, IL_FALSE, low_val)) : NULL;
 	log_reg_write(bundle, reg_num, op->class, false, true);
-	if (write_high) {
+
+	if (write_high && write_low) {
 		return SEQ2(write_low, write_high);
+	} else if (write_low) {
+		return write_low;
+	} else if (write_high) {
+		return write_high;
 	}
-	return write_low;
+	return EMPTY();
 }
 
 static inline bool read_cond_faulty(RzILOpPure *low_val, RzILOpPure *high_val, ut32 val_width) {