[PATCH PR target/67366 2/2] [gimple-fold.c] Support movmisalign optabs in gimple...
authorRamana Radhakrishnan <ramana@gcc.gnu.org>
Fri, 9 Oct 2015 10:58:06 +0000 (10:58 +0000)
committerRamana Radhakrishnan <ramana@gcc.gnu.org>
Fri, 9 Oct 2015 10:58:06 +0000 (10:58 +0000)
This patch by Richard allows for movmisalign optabs to be supported
in gimple-fold.c. This caused a bit of pain in the testsuite with strlenopt-8.c
in conjunction with the ARM support for movmisalign_optabs as the test
was coded up to do different things depending on whether the target
supported misaligned access or not. However now with unaligned access
being allowed for different levels of the architecture in the arm backend,
the concept of the helper function non_strict_align mapping identically
to the definition of STRICT_ALIGNMENT disappears.

Adjusted thusly for ARM. The testsuite/lib changes were tested with an
arm-none-eabi multilib that included architecture variants that did not
support unaligned access and architecture variants that did.

The testing matrix for this patch was:

1. x86_64 bootstrap and regression test - no regressions.
2. armhf bootstrap and regression test - no regressions.
3. arm-none-eabi cross build and regression test for

{-marm/-march=armv7-a/-mfpu=vfpv3-d16/-mfloat-abi=softfp}
{-mthumb/-march=armv8-a/-mfpu=crypto-neon-fp-armv8/-mfloat-abi=hard}
{-marm/-mcpu=arm7tdmi/-mfloat-abi=soft}
{-mthumb/-mcpu=arm7tdmi/-mfloat-abi=soft}

with no regressions.

Ok to apply ?

2015-10-09  Richard Biener  <rguenth@suse.de>

PR target/67366
* gimple-fold.c (optabs-query.h): Include
(gimple_fold_builtin_memory_op): Allow unaligned stores
when movmisalign_optabs are available.

2015-10-09  Ramana Radhakrishnan  <ramana.radhakrishnan@arm.com>

PR target/67366
* lib/target-supports.exp (check_effective_target_non_strict_align):
Adjust for arm*-*-*.
* gcc.target/arm/pr67366.c: New test.

From-SVN: r228644

gcc/ChangeLog
gcc/gimple-fold.c
gcc/testsuite/ChangeLog
gcc/testsuite/gcc.target/arm/pr67366.c [new file with mode: 0644]
gcc/testsuite/lib/target-supports.exp

index 8f096c7b4b0a3e0e002914fa2c168282cfe74b0e..514bb313b4d853c9c6b3a3bcb10209ef683cd81e 100644 (file)
@@ -1,3 +1,10 @@
+2015-10-09  Richard Biener  <rguenth@suse.de>
+
+       PR target/67366
+       * gimple-fold.c (optabs-query.h): Include
+       (gimple_fold_builtin_memory_op): Allow unaligned stores
+       when movmisalign_optabs are available.
+
 2015-10-09  Ramana Radhakrishnan  <ramana.radhakrishnan@arm.com>
 
         PR target/67366
index ee2a320c1fcbd8eaacf531c8f053a332d15760f3..17a23d65f39249cfea1d02a3e8bf5ca7c9acd447 100644 (file)
@@ -63,6 +63,8 @@ along with GCC; see the file COPYING3.  If not see
 #include "tree-eh.h"
 #include "gimple-match.h"
 #include "gomp-constants.h"
+#include "optabs-query.h"
+
 
 /* Return true when DECL can be referenced from current unit.
    FROM_DECL (if non-null) specify constructor of variable DECL was taken from.
@@ -709,7 +711,9 @@ gimple_fold_builtin_memory_op (gimple_stmt_iterator *gsi,
                  /* If the destination pointer is not aligned we must be able
                     to emit an unaligned store.  */
                  && (dest_align >= GET_MODE_ALIGNMENT (TYPE_MODE (type))
-                     || !SLOW_UNALIGNED_ACCESS (TYPE_MODE (type), dest_align)))
+                     || !SLOW_UNALIGNED_ACCESS (TYPE_MODE (type), dest_align)
+                     || (optab_handler (movmisalign_optab, TYPE_MODE (type))
+                         != CODE_FOR_nothing)))
                {
                  tree srctype = type;
                  tree desttype = type;
@@ -721,7 +725,10 @@ gimple_fold_builtin_memory_op (gimple_stmt_iterator *gsi,
                    srcmem = tem;
                  else if (src_align < GET_MODE_ALIGNMENT (TYPE_MODE (type))
                           && SLOW_UNALIGNED_ACCESS (TYPE_MODE (type),
-                                                    src_align))
+                                                    src_align)
+                          && (optab_handler (movmisalign_optab,
+                                             TYPE_MODE (type))
+                              == CODE_FOR_nothing))
                    srcmem = NULL_TREE;
                  if (srcmem)
                    {
index 6ce8fab13935c300c0de10a498d22df04089c04a..d7eba156ccb54e4e5d7673f16bb9d4b4543fbf28 100644 (file)
@@ -1,3 +1,10 @@
+2015-10-09  Ramana Radhakrishnan  <ramana.radhakrishnan@arm.com>
+
+       PR target/67366
+       * lib/target-supports.exp (check_effective_target_non_strict_align):
+       Adjust for arm*-*-*.
+       * gcc.target/arm/pr67366.c: New test.
+
 2015-10-09  Richard Biener  <rguenther@suse.de>
 
        PR tree-optimization/67891
diff --git a/gcc/testsuite/gcc.target/arm/pr67366.c b/gcc/testsuite/gcc.target/arm/pr67366.c
new file mode 100644 (file)
index 0000000..1e8b672
--- /dev/null
@@ -0,0 +1,14 @@
+/* { dg-do compile } */
+/* { dg-require-effective-target arm_unaligned } */
+/* { dg-options "-O2" } */
+
+typedef unsigned int u32;
+u32
+read32 (const void* ptr)
+{
+  u32 v;
+  __builtin_memcpy (&v, ptr, sizeof(v));
+  return v;
+}
+
+/* { dg-final { scan-assembler "@ unaligned" } } */
index 9057a27c6b4390c62e2699d00e46d5fb5d7f8bbc..4d5b0a3df61ee427df18af681f9d7a954f148bc4 100644 (file)
@@ -6262,6 +6262,15 @@ proc check_vect_support_and_set_flags { } {
 # Return 1 if the target does *not* require strict alignment.
 
 proc check_effective_target_non_strict_align {} {
+
+    # On ARM, the default is to use STRICT_ALIGNMENT, but there
+    # are interfaces defined for misaligned access and thus
+    # depending on the architecture levels unaligned access is
+    # available.
+    if [istarget "arm*-*-*"] {
+       return [check_effective_target_arm_unaligned]
+    }
+
     return [check_no_compiler_messages non_strict_align assembly {
        char *y;
        typedef char __attribute__ ((__aligned__(__BIGGEST_ALIGNMENT__))) c;