re PR target/77904 ([ARM Cortex-M0] Frame pointer thrashes registers if assembly...

2016-11-22  Thomas Preud'homme  <thomas.preudhomme@arm.com>

    gcc/
    PR target/77904
    * config/arm/arm.c (thumb1_compute_save_reg_mask): Mark frame pointer
    in save register mask if it is needed.

    gcc/testsuite/
    PR target/77904
    * gcc.target/arm/pr77904.c: New test.

From-SVN: r242693

diff --git a/gcc/ChangeLog b/gcc/ChangeLog
index 1bc5856..f5e1e54 100644 (file)
--- a/gcc/ChangeLog
+++ b/gcc/ChangeLog
@@ -1,3 +1,9 @@
+2016-11-22  Thomas Preud'homme  <thomas.preudhomme@arm.com>
+
+       PR target/77904
+       * config/arm/arm.c (thumb1_compute_save_reg_mask): Mark frame pointer
+       in save register mask if it is needed.
+
 2016-11-22  Jakub Jelinek  <jakub@redhat.com>
 
        PR tree-optimization/78436

diff --git a/gcc/config/arm/arm.c b/gcc/config/arm/arm.c
index dc88853..abd3276 100644 (file)
--- a/gcc/config/arm/arm.c
+++ b/gcc/config/arm/arm.c
@@ -18275,6 +18275,10 @@ thumb1_compute_save_reg_mask (void)
     if (df_regs_ever_live_p (reg) && callee_saved_reg_p (reg))
       mask |= 1 << reg;
 
+  /* Handle the frame pointer as a special case.  */
+  if (frame_pointer_needed)
+    mask |= 1 << HARD_FRAME_POINTER_REGNUM;
+
   if (flag_pic
       && !TARGET_SINGLE_PIC_BASE
       && arm_pic_register != INVALID_REGNUM

diff --git a/gcc/testsuite/ChangeLog b/gcc/testsuite/ChangeLog
index 3aec5a1..edcc79e 100644 (file)
--- a/gcc/testsuite/ChangeLog
+++ b/gcc/testsuite/ChangeLog
@@ -1,3 +1,8 @@
+2016-11-22  Thomas Preud'homme  <thomas.preudhomme@arm.com>
+
+       PR target/77904
+       * gcc.target/arm/pr77904.c: New test.
+
 2016-11-22  Toma Tabacu  <toma.tabacu@imgtec.com>
 
        * gcc.target/mips/interrupt_handler-bug-1.c (dg-options): Add

diff --git a/gcc/testsuite/gcc.target/arm/pr77904.c b/gcc/testsuite/gcc.target/arm/pr77904.c
new file mode 100644 (file)
index 0000000..76728c0
--- /dev/null
+++ b/gcc/testsuite/gcc.target/arm/pr77904.c
@@ -0,0 +1,45 @@
+/* { dg-do run } */
+/* { dg-options "-O2" } */
+
+__attribute__ ((noinline, noclone)) void
+clobber_sp (void)
+{
+  __asm volatile ("" : : : "sp");
+}
+
+int
+main (void)
+{
+  int ret;
+
+  __asm volatile ("mov\tr4, #0xf4\n\t"
+                 "mov\tr5, #0xf5\n\t"
+                 "mov\tr6, #0xf6\n\t"
+                 "mov\tr7, #0xf7\n\t"
+                 "mov\tr0, #0xf8\n\t"
+                 "mov\tr8, r0\n\t"
+                 "mov\tr0, #0xfa\n\t"
+                 "mov\tr10, r0"
+                 : : : "r0", "r4", "r5", "r6", "r7", "r8", "r10");
+  clobber_sp ();
+
+  __asm volatile ("cmp\tr4, #0xf4\n\t"
+                 "bne\tfail\n\t"
+                 "cmp\tr5, #0xf5\n\t"
+                 "bne\tfail\n\t"
+                 "cmp\tr6, #0xf6\n\t"
+                 "bne\tfail\n\t"
+                 "cmp\tr7, #0xf7\n\t"
+                 "bne\tfail\n\t"
+                 "mov\tr0, r8\n\t"
+                 "cmp\tr0, #0xf8\n\t"
+                 "bne\tfail\n\t"
+                 "mov\tr0, r10\n\t"
+                 "cmp\tr0, #0xfa\n\t"
+                 "bne\tfail\n\t"
+                 "mov\t%0, #1\n"
+                 "fail:\n\t"
+                 "sub\tr0, #1"
+                 : "=r" (ret) : :);
+  return ret;
+}