re PR target/60991 ([avr] Stack corruption when using 24-bit integers __int24 or…

re PR target/60991 ([avr] Stack corruption when using 24-bit integers __int24 or __memx pointers in large stack frame)

gcc/ChangeLog

	PR target/60991
	* config/avr/avr.c (avr_out_store_psi): Use correct constant
	to restore Y.

gcc/testsuite/ChangeLog

	PR target/60991
	* gcc.target/avr/pr60991.c: New testcase.

From-SVN: r210325

gcc/ChangeLog

+2014-05-12  Senthil Kumar Selvaraj  <senthil_kumar.selvaraj@atmel.com>
+
+	PR target/60991
+	* config/avr/avr.c (avr_out_store_psi): Use correct constant
+	to restore Y.
+
 2014-05-12  Georg-Johann Lay  <avr@gjlay.de>
 
 	* config/arm/arm.h (License): Add GCC Runtime Library Exception.

gcc/config/avr/avr.c

@@ -3999,7 +3999,7 @@ avr_out_store_psi (rtx insn, rtx *op, int *plen)
                                 "std Y+61,%A1"    CR_TAB
                                 "std Y+62,%B1"    CR_TAB
                                 "std Y+63,%C1"    CR_TAB
-                                "sbiw r28,%o0-60", op, plen, -5);
+                                "sbiw r28,%o0-61", op, plen, -5);
 
           return avr_asm_len ("subi r28,lo8(-%o0)" CR_TAB
                               "sbci r29,hi8(-%o0)" CR_TAB

gcc/testsuite/ChangeLog

+2014-05-12  Senthil Kumar Selvaraj  <senthil_kumar.selvaraj@atmel.com>
+
+	PR target/60991
+	* gcc.target/avr/pr60991.c: New testcase.
+
 2014-05-12  Paolo Carlini  <paolo.carlini@oracle.com>
 
 	PR c++/60054

gcc/testsuite/gcc.target/avr/pr60991.c

+/* { dg-do run } */
+/* { dg-options "-O1" } */
+
+/* This testcase (simplified from the original bug report) exposes 
+   PR60991. The code generated for writing the __int24 value corrupts
+   the frame pointer if the offset is <= 63 + MAX_LD_OFFSET */
+
+#include <stdlib.h>
+
+int main(void)
+{
+    volatile char junk[62];
+    junk[0] = 5;
+    volatile __int24 staticConfig = 0;
+
+    if (junk[0] != 5)
+      abort();
+
+    exit(0);
+    return 0;
+}