Merge pull request capstone-engine#2121 from Rot127/arm-implicit-reads

[ARM] Add CPSR implicit read for every instruction with predicate

Mapping.c

@@ -85,6 +85,25 @@ void map_add_implicit_write(MCInst *MI, uint32_t Reg)
 	}
 }
 
+/// Adds a register to the implicit read register list.
+/// It will not add the same register twice.
+void map_add_implicit_read(MCInst *MI, uint32_t Reg)
+{
+	if (!MI->flat_insn->detail)
+		return;
+
+	uint16_t *regs_read = MI->flat_insn->detail->regs_read;
+	for (int i = 0; i < MAX_IMPL_W_REGS; ++i) {
+		if (i == MI->flat_insn->detail->regs_read_count) {
+			regs_read[i] = Reg;
+			MI->flat_insn->detail->regs_read_count++;
+			return;
+		}
+		if (regs_read[i] == Reg)
+			return;
+	}
+}
+
 /// Removes a register from the implicit write register list.
 void map_remove_implicit_write(MCInst *MI, uint32_t Reg)
 {
@@ -160,7 +179,8 @@ void map_implicit_writes(MCInst *MI, const insn_map *imap)
 }
 
 /// Adds a given group to @MI->flat_insn.
-void add_group(MCInst *MI, unsigned /* arch_group */ group) {
+void add_group(MCInst *MI, unsigned /* arch_group */ group)
+{
 #ifndef CAPSTONE_DIET
 	if (!MI->flat_insn->detail)
 		return;

Mapping.h

@@ -21,9 +21,9 @@ typedef struct insn_map {
 	unsigned short mapid;		    // The Capstone instruction id
 #ifndef CAPSTONE_DIET
 	uint16_t regs_use[MAX_IMPL_R_REGS]; ///< list of implicit registers used by
-		///< this instruction
+					    ///< this instruction
 	uint16_t regs_mod[MAX_IMPL_W_REGS]; ///< list of implicit registers modified
-		///< by this instruction
+					    ///< by this instruction
 	unsigned char groups
 		[MAX_NUM_GROUPS]; ///< list of group this instruction belong to
 	bool branch;		  // branch instruction?
@@ -47,7 +47,7 @@ typedef struct {
 	uint8_t /* cs_ac_type */ access; ///< The access type (read, write)
 	uint8_t				 /* cs_data_type */
 		dtypes[MAX_NO_DATA_TYPES]; ///< List of op types. Terminated by
-		///< CS_DATA_TYPE_LAST
+					   ///< CS_DATA_TYPE_LAST
 } mapping_op;
 
 #define MAX_NO_INSN_MAP_OPS 16
@@ -98,6 +98,7 @@ int name2id(const name_map *map, int max, const char *name);
 const char *id2name(const name_map *map, int max, const unsigned int id);
 
 void map_add_implicit_write(MCInst *MI, uint32_t Reg);
+void map_add_implicit_read(MCInst *MI, uint32_t Reg);
 void map_remove_implicit_write(MCInst *MI, uint32_t Reg);
 
 void map_implicit_reads(MCInst *MI, const insn_map *imap);

arch/ARM/ARMMapping.c

@@ -868,6 +868,8 @@ static void add_cs_detail_general(MCInst *MI, arm_op_group op_group,
 			return;
 		}
 		ARM_get_detail(MI)->cc = CC;
+		if (CC != ARMCC_AL)
+			map_add_implicit_read(MI, ARM_REG_CPSR);
 		break;
 	}
 	case ARM_OP_GROUP_VPTPredicateOperand: {