pru: Enable section anchoring by default

Loading an arbitrary constant address in a register is expensive for
PRU.  So enable section anchoring by default to utilize the unsigned
byte constant offset operand of load/store instructions.

gcc/ChangeLog:

	* common/config/pru/pru-common.cc
	(TARGET_OPTION_OPTIMIZATION_TABLE): New definition.
	* config/pru/pru.cc (TARGET_MIN_ANCHOR_OFFSET): Set minimal
	anchor offset.
	(TARGET_MAX_ANCHOR_OFFSET): Set maximum anchor offset.

gcc/testsuite/ChangeLog:

	* gcc.target/pru/section-anchors-1.c: New test.
	* gcc.target/pru/section-anchors-2.c: New test.

Signed-off-by: Dimitar Dimitrov <dimitar@dinux.eu>

diff --git a/gcc/common/config/pru/pru-common.cc b/gcc/common/config/pru/pru-common.cc
index e8dbf28b2d288412523a57dc214e7abb96610973..cdc31783dfd03a99c4a8258948cf3cbe3222a440 100644 (file)
--- a/gcc/common/config/pru/pru-common.cc
+++ b/gcc/common/config/pru/pru-common.cc
@@ -33,4 +33,16 @@ along with GCC; see the file COPYING3.  If not see
 #undef TARGET_EXCEPT_UNWIND_INFO
 #define TARGET_EXCEPT_UNWIND_INFO sjlj_except_unwind_info
 
+#undef  TARGET_OPTION_OPTIMIZATION_TABLE
+#define TARGET_OPTION_OPTIMIZATION_TABLE pru_option_optimization_table
+
+/* Set default optimization options.  */
+static const struct default_options pru_option_optimization_table[] =
+  {
+    /* Enable section anchors by default at -O1 or higher.  */
+    { OPT_LEVELS_1_PLUS, OPT_fsection_anchors, NULL, 1 },
+
+    { OPT_LEVELS_NONE, 0, NULL, 0 }
+  };
+
 struct gcc_targetm_common targetm_common = TARGETM_COMMON_INITIALIZER;

diff --git a/gcc/config/pru/pru.cc b/gcc/config/pru/pru.cc
index 491f66432b372e6d862418424cb8b60d76d9987a..d070007918720a66c3dbe7bcfb250b0eeb1ed90f 100644 (file)
--- a/gcc/config/pru/pru.cc
+++ b/gcc/config/pru/pru.cc
@@ -3249,6 +3249,12 @@ pru_unwind_word_mode (void)
 #undef TARGET_PRINT_OPERAND_ADDRESS
 #define TARGET_PRINT_OPERAND_ADDRESS pru_print_operand_address
 
+#undef  TARGET_MIN_ANCHOR_OFFSET
+#define TARGET_MIN_ANCHOR_OFFSET  0
+
+#undef  TARGET_MAX_ANCHOR_OFFSET
+#define TARGET_MAX_ANCHOR_OFFSET  255
+
 #undef TARGET_OPTION_OVERRIDE
 #define TARGET_OPTION_OVERRIDE pru_option_override
 

diff --git a/gcc/testsuite/gcc.target/pru/section-anchors-1.c b/gcc/testsuite/gcc.target/pru/section-anchors-1.c
new file mode 100644 (file)
index 0000000..4c8da51
--- /dev/null
+++ b/gcc/testsuite/gcc.target/pru/section-anchors-1.c
@@ -0,0 +1,14 @@
+/* Ensure section anchors are enabled by default.  */
+
+/* { dg-do assemble } */
+/* { dg-options "-O1" } */
+/* { dg-final { object-size text == 24 } } */
+
+int aa;
+int bb;
+
+int
+test (void)
+{
+  return aa + bb;
+}

diff --git a/gcc/testsuite/gcc.target/pru/section-anchors-2.c b/gcc/testsuite/gcc.target/pru/section-anchors-2.c
new file mode 100644 (file)
index 0000000..bd5467e
--- /dev/null
+++ b/gcc/testsuite/gcc.target/pru/section-anchors-2.c
@@ -0,0 +1,14 @@
+/* Ensure section anchors are enabled by default.  */
+
+/* { dg-do compile } */
+/* { dg-options "-O1" } */
+
+int aa;
+int bb;
+
+int
+test (void)
+{
+  return aa + bb;
+  /* { dg-final { scan-assembler {\n\tldi32\tr\d+, \.LANCHOR\d+} } } */
+}