[gcc r15-2455] pru: Enable section anchoring by default

[Dimitar Dimitrov via Gcc-cvs]

https://gcc.gnu.org/g:dcdefe47e18fabc340f9862a27ebd521dfa3d38c

commit r15-2455-gdcdefe47e18fabc340f9862a27ebd521dfa3d38c
Author: Dimitar Dimitrov <dimi...@dinux.eu>
Date:   Sun Jul 14 19:45:09 2024 +0300

    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 <dimi...@dinux.eu>

Diff:
---
 gcc/common/config/pru/pru-common.cc              | 12 ++++++++++++
 gcc/config/pru/pru.cc                            |  6 ++++++
 gcc/testsuite/gcc.target/pru/section-anchors-1.c | 14 ++++++++++++++
 gcc/testsuite/gcc.target/pru/section-anchors-2.c | 14 ++++++++++++++
 4 files changed, 46 insertions(+)

diff --git a/gcc/common/config/pru/pru-common.cc 
b/gcc/common/config/pru/pru-common.cc
index e8dbf28b2d28..cdc31783dfd0 100644
--- 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 491f66432b37..d07000791872 100644
--- 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
index 000000000000..4c8da5136c31
--- /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
index 000000000000..bd5467edad99
--- /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+} } } */
+}