PR78255: Make postreload aware of NO_FUNCTION_CSE

gcc/ChangeLog:
2016-12-09  Andre Vieira <andre.simoesdiasvieira@arm.com>

	PR rtl-optimization/78255
	* gcc/postreload.c (reload_cse_simplify): Do not CSE a function if
	NO_FUNCTION_CSE is true.

gcc/testsuite/ChangeLog:
2016-12-09  Andre Vieira <andre.simoesdiasvieira@arm.com>

	PR rtl-optimization/78255
	* gcc.target/aarch64/pr78255.c: New.
	* gcc.target/arm/pr78255-1.c: New.
	* gcc.target/arm/pr78255-2.c: New.

From-SVN: r243494

gcc/ChangeLog

+2016-12-09  Andre Vieira <andre.simoesdiasvieira@arm.com>
+
+	PR rtl-optimization/78255
+	* gcc/postreload.c (reload_cse_simplify): Do not CSE a function if
+	NO_FUNCTION_CSE is true.
+
 2016-12-09  Cesar Philippidis  <cesar@codesourcery.com>
 
 	PR ipa/78027

gcc/postreload.c

@@ -90,6 +90,11 @@ reload_cse_simplify (rtx_insn *insn, rtx testreg)
   basic_block insn_bb = BLOCK_FOR_INSN (insn);
   unsigned insn_bb_succs = EDGE_COUNT (insn_bb->succs);
 
+  /* If NO_FUNCTION_CSE has been set by the target, then we should not try
+     to cse function calls.  */
+  if (NO_FUNCTION_CSE && CALL_P (insn))
+    return false;
+
   if (GET_CODE (body) == SET)
     {
       int count = 0;

gcc/testsuite/ChangeLog

+2016-12-09  Andre Vieira <andre.simoesdiasvieira@arm.com>
+
+	PR rtl-optimization/78255
+	* gcc.target/aarch64/pr78255.c: New.
+	* gcc.target/arm/pr78255-1.c: New.
+	* gcc.target/arm/pr78255-2.c: New.
+
 2016-12-09  Will Schmidt  <will_schmidt@vnet.ibm.com>
 
 	* gcc.target/powerpc/dimode-1.c: Update syntax on scan-assembler

gcc/testsuite/gcc.target/aarch64/pr78255.c

+/* { dg-do compile } */
+/* { dg-options "-O2 -mcmodel=tiny" } */
+
+extern int bar (void *);
+
+int
+foo (void)
+{
+  return bar ((void *)bar);
+}
+
+/* { dg-final { scan-assembler "b\\s+bar" } } */

gcc/testsuite/gcc.target/arm/pr78255-1.c

+/* { dg-do run } */
+/* { dg-options "-O2" }  */
+
+#include <string.h>
+
+struct table_s
+    {
+    void (*fun0)
+        ( void );
+    void (*fun1)
+        ( void );
+    void (*fun2)
+        ( void );
+    void (*fun3)
+        ( void );
+    void (*fun4)
+        ( void );
+    void (*fun5)
+        ( void );
+    void (*fun6)
+        ( void );
+    void (*fun7)
+        ( void );
+    } table;
+
+void callback0(){__asm("mov r0, r0 \n\t");}
+void callback1(){__asm("mov r0, r0 \n\t");}
+void callback2(){__asm("mov r0, r0 \n\t");}
+void callback3(){__asm("mov r0, r0 \n\t");}
+void callback4(){__asm("mov r0, r0 \n\t");}
+
+void test (void) {
+    memset(&table, 0, sizeof table);
+
+    asm volatile ("" : : : "r3");
+
+    table.fun0 = callback0;
+    table.fun1 = callback1;
+    table.fun2 = callback2;
+    table.fun3 = callback3;
+    table.fun4 = callback4;
+    table.fun0();
+}
+
+void foo (void)
+{
+  __builtin_abort ();
+}
+
+int main (void)
+{
+  unsigned long p = (unsigned long) &foo;
+  asm volatile ("mov r3, %0" : : "r" (p));
+  test ();
+
+  return 0;
+}

gcc/testsuite/gcc.target/arm/pr78255-2.c

+/* { dg-do compile } */
+/* { dg-options "-O2" }  */
+
+extern int bar (void *);
+
+int
+foo (void)
+{
+  return bar ((void*)bar);
+}
+
+/* { dg-final { scan-assembler "b\\s+bar" } } */