gcc/

2014-08-22  Yvan Roux  <yvan.roux@linaro.org>

	Backport from trunk r212927, r213304.
	2014-07-30  Jiong Wang  <jiong.wang@arm.com>

	* config/arm/arm.c (arm_get_frame_offsets): Adjust condition for
	Thumb2.

	2014-07-23  Jiong Wang  <jiong.wang@arm.com>

	* config/arm/arm.c (arm_get_frame_offsets): If both r3 and other
	callee-saved registers are available for padding purpose
	and r3 is not mandatory, then prefer use those callee-saved
	instead of r3.

gcc/testsuite/
2014-08-22  Yvan Roux  <yvan.roux@linaro.org>

	Backport from trunk r212927.
	2014-07-23  Jiong Wang  <jiong.wang@arm.com>

	* gcc.dg/ira-shrinkwrap-prep-1.c (target): Add arm_nothumb.
	* gcc.dg/ira-shrinkwrap-prep-2.c (target): Likewise.
	* gcc.dg/pr10474.c (target): Likewise.

git-svn-id: svn+ssh://gcc.gnu.org/svn/gcc/branches/linaro/gcc-4_9-branch@214314 138bc75d-0d04-0410-961f-82ee72b054a4

diff --git a/gcc/ChangeLog.linaro b/gcc/ChangeLog.linaro
index 39fbd71..3781582 100644 (file)
--- a/gcc/ChangeLog.linaro
+++ b/gcc/ChangeLog.linaro
@@ -1,5 +1,20 @@
 2014-08-22  Yvan Roux  <yvan.roux@linaro.org>
 
+       Backport from trunk r212927, r213304.
+       2014-07-30  Jiong Wang  <jiong.wang@arm.com>
+
+       * config/arm/arm.c (arm_get_frame_offsets): Adjust condition for
+       Thumb2.
+
+       2014-07-23  Jiong Wang  <jiong.wang@arm.com>
+
+       * config/arm/arm.c (arm_get_frame_offsets): If both r3 and other
+       callee-saved registers are available for padding purpose
+       and r3 is not mandatory, then prefer use those callee-saved
+       instead of r3.
+
+2014-08-22  Yvan Roux  <yvan.roux@linaro.org>
+
        Backport from trunk r211717, r213692.
        2014-08-07  Kugan Vivekanandarajah  <kuganv@linaro.org>
 

diff --git a/gcc/config/arm/arm.c b/gcc/config/arm/arm.c
index 2f88c1c..a9c53dc 100644 (file)
--- a/gcc/config/arm/arm.c
+++ b/gcc/config/arm/arm.c
@@ -20772,30 +20772,47 @@ arm_get_frame_offsets (void)
        {
          int reg = -1;
 
+         /* Register r3 is caller-saved.  Normally it does not need to be
+            saved on entry by the prologue.  However if we choose to save
+            it for padding then we may confuse the compiler into thinking
+            a prologue sequence is required when in fact it is not.  This
+            will occur when shrink-wrapping if r3 is used as a scratch
+            register and there are no other callee-saved writes.
+
+            This situation can be avoided when other callee-saved registers
+            are available and r3 is not mandatory if we choose a callee-saved
+            register for padding.  */
+         bool prefer_callee_reg_p = false;
+
          /* If it is safe to use r3, then do so.  This sometimes
             generates better code on Thumb-2 by avoiding the need to
             use 32-bit push/pop instructions.  */
           if (! any_sibcall_could_use_r3 ()
              && arm_size_return_regs () <= 12
              && (offsets->saved_regs_mask & (1 << 3)) == 0
-              && (TARGET_THUMB2
+             && (TARGET_THUMB2
                  || !(TARGET_LDRD && current_tune->prefer_ldrd_strd)))
            {
              reg = 3;
+             if (!TARGET_THUMB2)
+               prefer_callee_reg_p = true;
+           }
+         if (reg == -1
+             || prefer_callee_reg_p)
+           {
+             for (i = 4; i <= (TARGET_THUMB1 ? LAST_LO_REGNUM : 11); i++)
+               {
+                 /* Avoid fixed registers; they may be changed at
+                    arbitrary times so it's unsafe to restore them
+                    during the epilogue.  */
+                 if (!fixed_regs[i]
+                     && (offsets->saved_regs_mask & (1 << i)) == 0)
+                   {
+                     reg = i;
+                     break;
+                   }
+               }
            }
-         else
-           for (i = 4; i <= (TARGET_THUMB1 ? LAST_LO_REGNUM : 11); i++)
-             {
-               /* Avoid fixed registers; they may be changed at
-                  arbitrary times so it's unsafe to restore them
-                  during the epilogue.  */
-               if (!fixed_regs[i]
-                   && (offsets->saved_regs_mask & (1 << i)) == 0)
-                 {
-                   reg = i;
-                   break;
-                 }
-             }
 
          if (reg != -1)
            {

diff --git a/gcc/testsuite/ChangeLog.linaro b/gcc/testsuite/ChangeLog.linaro
index cfe89af..a033dbd 100644 (file)
--- a/gcc/testsuite/ChangeLog.linaro
+++ b/gcc/testsuite/ChangeLog.linaro
@@ -1,3 +1,12 @@
+2014-08-22  Yvan Roux  <yvan.roux@linaro.org>
+
+       Backport from trunk r212927.
+       2014-07-23  Jiong Wang  <jiong.wang@arm.com>
+
+       * gcc.dg/ira-shrinkwrap-prep-1.c (target): Add arm_nothumb.
+       * gcc.dg/ira-shrinkwrap-prep-2.c (target): Likewise.
+       * gcc.dg/pr10474.c (target): Likewise.
+
 2014-08-14  Yvan Roux  <yvan.roux@linaro.org>
 
        GCC Linaro 4.9-2014.08 released.

diff --git a/gcc/testsuite/gcc.dg/ira-shrinkwrap-prep-1.c b/gcc/testsuite/gcc.dg/ira-shrinkwrap-prep-1.c
index 54d3e76..1025218 100644 (file)
--- a/gcc/testsuite/gcc.dg/ira-shrinkwrap-prep-1.c
+++ b/gcc/testsuite/gcc.dg/ira-shrinkwrap-prep-1.c
@@ -1,4 +1,4 @@
-/* { dg-do compile { target { { x86_64-*-* && lp64 } || { powerpc*-*-* && lp64 } } } } */
+/* { dg-do compile { target { { x86_64-*-* && lp64 } || { { powerpc*-*-* && lp64 } || arm_nothumb } } } } */
 /* { dg-options "-O3 -fdump-rtl-ira -fdump-rtl-pro_and_epilogue"  } */
 
 long __attribute__((noinline, noclone))

diff --git a/gcc/testsuite/gcc.dg/ira-shrinkwrap-prep-2.c b/gcc/testsuite/gcc.dg/ira-shrinkwrap-prep-2.c
index ed08494..e945835 100644 (file)
--- a/gcc/testsuite/gcc.dg/ira-shrinkwrap-prep-2.c
+++ b/gcc/testsuite/gcc.dg/ira-shrinkwrap-prep-2.c
@@ -1,4 +1,4 @@
-/* { dg-do compile { target { { x86_64-*-* && lp64 } || { powerpc*-*-* && lp64 } } } } */
+/* { dg-do compile { target { { x86_64-*-* && lp64 } || { { powerpc*-*-* && lp64 } || arm_nothumb } } } } */
 /* { dg-options "-O3 -fdump-rtl-ira -fdump-rtl-pro_and_epilogue"  } */
 
 long __attribute__((noinline, noclone))

diff --git a/gcc/testsuite/gcc.dg/pr10474.c b/gcc/testsuite/gcc.dg/pr10474.c
index 77ccc46..803fa10 100644 (file)
--- a/gcc/testsuite/gcc.dg/pr10474.c
+++ b/gcc/testsuite/gcc.dg/pr10474.c
@@ -1,4 +1,4 @@
-/* { dg-do compile { target { { x86_64-*-* && lp64 } || { powerpc*-*-* && lp64 } } } } */
+/* { dg-do compile { target { { x86_64-*-* && lp64 } || { { powerpc*-*-* && lp64 } || arm_nothumb } } } } */
 /* { dg-options "-O3 -fdump-rtl-pro_and_epilogue"  } */
 
 void f(int *i)