x86_32_common: fix some warnings

Mostly "Dead assignment" reported by Clang static analyzer.

Change-Id: Ibf81d2ba2462570ee3a40e57a60c55a1d1fa0c00
Signed-off-by: Paul Fertser <fercerpav@gmail.com>
Reviewed-on: http://openocd.zylin.com/4351
Tested-by: jenkins

1 files changed, 28 insertions, 15 deletions

diff --git a/src/target/x86_32_common.c b/src/target/x86_32_common.c
index 0d87ba5..ef4f806 100644
--- a/src/target/x86_32_common.c
+++ b/src/target/x86_32_common.c
@@ -209,15 +209,16 @@ static int read_phys_mem(struct target *t, uint32_t phys_address,
 			LOG_ERROR("%s invalid read size", __func__);
 			break;
 		}
+		if (retval != ERROR_OK)
+			break;
 	}
 	/* restore CR0.PG bit if needed (regardless of retval) */
 	if (pg_disabled) {
-		retval = x86_32->enable_paging(t);
-		if (retval != ERROR_OK) {
+		int retval2 = x86_32->enable_paging(t);
+		if (retval2 != ERROR_OK) {
 			LOG_ERROR("%s could not enable paging", __func__);
-			return retval;
+			return retval2;
 		}
-		pg_disabled = true;
 	}
 	/* TODO: After reading memory from target, we must replace
 	 * software breakpoints with the original instructions again.
@@ -364,6 +365,9 @@ static int read_mem(struct target *t, uint32_t size,
 			break;
 	}
 
+	if (retval != ERROR_OK)
+		return retval;
+
 	/* read_hw_reg() will write to 4 bytes (uint32_t)
 	 * Watch out, the buffer passed into read_mem() might be 1 or 2 bytes.
 	 */
@@ -436,6 +440,10 @@ static int write_mem(struct target *t, uint32_t size,
 			LOG_ERROR("%s invalid write mem size", __func__);
 			return ERROR_FAIL;
 	}
+
+	if (retval != ERROR_OK)
+		return retval;
+
 	retval = x86_32->transaction_status(t);
 	if (retval != ERROR_OK) {
 		LOG_ERROR("%s error on mem write", __func__);
@@ -606,7 +614,6 @@ int x86_32_common_read_memory(struct target *t, target_addr_t addr,
 			&& x86_32_common_read_phys_mem(t, physaddr, size, count, buf) != ERROR_OK) {
 			LOG_ERROR("%s failed to read memory from physical address " TARGET_ADDR_FMT,
 					  __func__, physaddr);
-			retval = ERROR_FAIL;
 		}
 		/* restore PG bit if it was cleared prior (regardless of retval) */
 		retval = x86_32->enable_paging(t);
@@ -662,7 +669,6 @@ int x86_32_common_write_memory(struct target *t, target_addr_t addr,
 			&& x86_32_common_write_phys_mem(t, physaddr, size, count, buf) != ERROR_OK) {
 			LOG_ERROR("%s failed to write memory to physical address " TARGET_ADDR_FMT,
 					__func__, physaddr);
-			retval = ERROR_FAIL;
 		}
 		/* restore PG bit if it was cleared prior (regardless of retval) */
 		retval = x86_32->enable_paging(t);
@@ -733,15 +739,19 @@ int x86_32_common_read_io(struct target *t, uint32_t addr,
 			LOG_ERROR("%s invalid read io size", __func__);
 			return ERROR_FAIL;
 	}
+
 	/* restore CR0.PG bit if needed */
 	if (pg_disabled) {
-		retval = x86_32->enable_paging(t);
-		if (retval != ERROR_OK) {
+		int retval2 = x86_32->enable_paging(t);
+		if (retval2 != ERROR_OK) {
 			LOG_ERROR("%s could not enable paging", __func__);
-			return retval;
+			return retval2;
 		}
-		pg_disabled = false;
 	}
+
+	if (retval != ERROR_OK)
+		return retval;
+
 	uint32_t regval = 0;
 	retval = x86_32->read_hw_reg(t, EAX, &regval, 0);
 	if (retval != ERROR_OK) {
@@ -818,15 +828,19 @@ int x86_32_common_write_io(struct target *t, uint32_t addr,
 			LOG_ERROR("%s invalid write io size", __func__);
 			return ERROR_FAIL;
 	}
+
 	/* restore CR0.PG bit if needed */
 	if (pg_disabled) {
-		retval = x86_32->enable_paging(t);
-		if (retval != ERROR_OK) {
+		int retval2 = x86_32->enable_paging(t);
+		if (retval2 != ERROR_OK) {
 			LOG_ERROR("%s could not enable paging", __func__);
-			return retval;
+			return retval2;
 		}
-		pg_disabled = false;
 	}
+
+	if (retval != ERROR_OK)
+		return retval;
+
 	retval = x86_32->transaction_status(t);
 	if (retval != ERROR_OK) {
 		LOG_ERROR("%s error on io write", __func__);
@@ -1141,7 +1155,6 @@ static int set_breakpoint(struct target *t, struct breakpoint *bp)
 			}
 		} else {
 			LOG_ERROR("%s core doesn't support SW breakpoints", __func__);
-			error = ERROR_FAIL;
 			return ERROR_FAIL;
 		}
 	}