Some nit comments.
+static bool
+riscv_frame_pointer_required (void)
+{
+ if (riscv_save_frame_pointer && !crtl->is_leaf)
+ return true;
+
+ return false;
+}
Can be simplified to return riscv_save_frame_pointer && !crtl->is_leaf;
+ riscv_save_frame_pointer = false;
+ if (TARGET_OMIT_LEAF_FRAME_POINTER_P (global_options.x_target_flags))
+ {
+ if (!global_options.x_flag_omit_frame_pointer)
+ riscv_save_frame_pointer = true;
+
+ global_options.x_flag_omit_frame_pointer = 1;
+ }
Does this mean if omit_leaf_frame will also set the omit_frame_pointer
implicitly?
Pan
-----Original Message-----
From: Wang, Yanzhang <yanzhang.w...@intel.com>
Sent: Friday, June 2, 2023 3:07 PM
To: gcc-patches@gcc.gnu.org
Cc: juzhe.zh...@rivai.ai; kito.ch...@sifive.com; Li, Pan2 <pan2...@intel.com>;
Wang, Yanzhang <yanzhang.w...@intel.com>
Subject: [PATCH] RISCV: Add -m(no)-omit-leaf-frame-pointer support.
From: Yanzhang Wang <yanzhang.w...@intel.com>
gcc/ChangeLog:
* config/riscv/riscv.cc (riscv_save_reg_p): Save ra for leaf
when enabling -mno-omit-leaf-frame-pointer
(riscv_option_override): Override omit-frame-pointer.
(riscv_frame_pointer_required): Save s0 for non-leaf function
(TARGET_FRAME_POINTER_REQUIRED): Override defination
* config/riscv/riscv.opt: Add option support.
gcc/testsuite/ChangeLog:
* gcc.target/riscv/omit-frame-pointer-1.c: New test.
* gcc.target/riscv/omit-frame-pointer-2.c: New test.
* gcc.target/riscv/omit-frame-pointer-3.c: New test.
* gcc.target/riscv/omit-frame-pointer-4.c: New test.
* gcc.target/riscv/omit-frame-pointer-test.c: New test.
Signed-off-by: Yanzhang Wang <yanzhang.w...@intel.com>
---
gcc/config/riscv/riscv.cc | 31 ++++++++++++++++++-
gcc/config/riscv/riscv.opt | 4 +++
.../gcc.target/riscv/omit-frame-pointer-1.c | 7 +++++
.../gcc.target/riscv/omit-frame-pointer-2.c | 7 +++++
.../gcc.target/riscv/omit-frame-pointer-3.c | 7 +++++
.../gcc.target/riscv/omit-frame-pointer-4.c | 7 +++++
.../riscv/omit-frame-pointer-test.c | 13 ++++++++
7 files changed, 75 insertions(+), 1 deletion(-)
create mode 100644 gcc/testsuite/gcc.target/riscv/omit-frame-pointer-1.c
create mode 100644 gcc/testsuite/gcc.target/riscv/omit-frame-pointer-2.c
create mode 100644 gcc/testsuite/gcc.target/riscv/omit-frame-pointer-3.c
create mode 100644 gcc/testsuite/gcc.target/riscv/omit-frame-pointer-4.c
create mode 100644 gcc/testsuite/gcc.target/riscv/omit-frame-pointer-test.c
diff --git a/gcc/config/riscv/riscv.cc b/gcc/config/riscv/riscv.cc
index 5d2550871c7..e02f9cb50a4 100644
--- a/gcc/config/riscv/riscv.cc
+++ b/gcc/config/riscv/riscv.cc
@@ -408,6 +408,10 @@ static const struct riscv_tune_info
riscv_tune_info_table[] = {
#include "riscv-cores.def"
};
+/* Global variable to distinguish whether we should save and restore s0/fp for
+ function. */
+static bool riscv_save_frame_pointer;
+
void riscv_frame_info::reset(void)
{
total_size = 0;
@@ -4744,7 +4748,11 @@ riscv_save_reg_p (unsigned int regno)
if (regno == HARD_FRAME_POINTER_REGNUM && frame_pointer_needed)
return true;
- if (regno == RETURN_ADDR_REGNUM && crtl->calls_eh_return)
+ /* Need not to use ra for leaf when frame pointer is turned off by option
+ whatever the omit-leaf-frame's value. */
+ bool keep_leaf_ra = frame_pointer_needed && crtl->is_leaf
+ && !TARGET_OMIT_LEAF_FRAME_POINTER;
+ if (regno == RETURN_ADDR_REGNUM && (crtl->calls_eh_return || keep_leaf_ra))
return true;
/* If this is an interrupt handler, then must save extra registers. */
@@ -6287,6 +6295,15 @@ riscv_option_override (void)
if (flag_pic)
riscv_cmodel = CM_PIC;
+ riscv_save_frame_pointer = false;
+ if (TARGET_OMIT_LEAF_FRAME_POINTER_P (global_options.x_target_flags))
+ {
+ if (!global_options.x_flag_omit_frame_pointer)
+ riscv_save_frame_pointer = true;
+
+ global_options.x_flag_omit_frame_pointer = 1;
+ }
+
/* We get better code with explicit relocs for CM_MEDLOW, but
worse code for the others (for now). Pick the best default. */
if ((target_flags_explicit & MASK_EXPLICIT_RELOCS) == 0)
@@ -7158,6 +7175,15 @@ riscv_zero_call_used_regs (HARD_REG_SET
need_zeroed_hardregs)
& ~zeroed_hardregs);
}
+static bool
+riscv_frame_pointer_required (void)
+{
+ if (riscv_save_frame_pointer && !crtl->is_leaf)
+ return true;
+
+ return false;
+}
+
/* Initialize the GCC target structure. */
#undef TARGET_ASM_ALIGNED_HI_OP
#define TARGET_ASM_ALIGNED_HI_OP "\t.half\t"
@@ -7412,6 +7438,9 @@ riscv_zero_call_used_regs (HARD_REG_SET
need_zeroed_hardregs)
#undef TARGET_ZERO_CALL_USED_REGS
#define TARGET_ZERO_CALL_USED_REGS riscv_zero_call_used_regs
+#undef TARGET_FRAME_POINTER_REQUIRED
+#define TARGET_FRAME_POINTER_REQUIRED riscv_frame_pointer_required
+
struct gcc_target targetm = TARGET_INITIALIZER;
#include "gt-riscv.h"
diff --git a/gcc/config/riscv/riscv.opt b/gcc/config/riscv/riscv.opt
index ff1dd4ddd4f..c3e2e7c1da4 100644
--- a/gcc/config/riscv/riscv.opt
+++ b/gcc/config/riscv/riscv.opt
@@ -138,6 +138,10 @@ Enable the CSR checking for the ISA-dependent CRS and the
read-only CSR.
The ISA-dependent CSR are only valid when the specific ISA is set. The
read-only CSR can not be written by the CSR instructions.
+momit-leaf-frame-pointer
+Target Mask (OMIT_LEAF_FRAME_POINTER) Save
+Omit the frame pointer in leaf functions.
+
Mask(64BIT)
Mask(MUL)
diff --git a/gcc/testsuite/gcc.target/riscv/omit-frame-pointer-1.c
b/gcc/testsuite/gcc.target/riscv/omit-frame-pointer-1.c
new file mode 100644
index 00000000000..c96123ea702
--- /dev/null
+++ b/gcc/testsuite/gcc.target/riscv/omit-frame-pointer-1.c
@@ -0,0 +1,7 @@
+/* { dg-do compile } */
+/* { dg-options "-march=rv64gc -mabi=lp64 -O2 -fno-omit-frame-pointer
-mno-omit-leaf-frame-pointer -fno-inline" } */
+
+#include "omit-frame-pointer-test.c"
+
+/* { dg-final { scan-assembler-times "sd\tra,\[0-9\]+\\(sp\\)" 2 } } */
+/* { dg-final { scan-assembler-times "sd\ts0,\[0-9\]+\\(sp\\)" 2 } } */
diff --git a/gcc/testsuite/gcc.target/riscv/omit-frame-pointer-2.c
b/gcc/testsuite/gcc.target/riscv/omit-frame-pointer-2.c
new file mode 100644
index 00000000000..067148c6a58
--- /dev/null
+++ b/gcc/testsuite/gcc.target/riscv/omit-frame-pointer-2.c
@@ -0,0 +1,7 @@
+/* { dg-do compile } */
+/* { dg-options "-march=rv64gc -mabi=lp64 -O2 -fno-omit-frame-pointer
-momit-leaf-frame-pointer -fno-inline" } */
+
+#include "omit-frame-pointer-test.c"
+
+/* { dg-final { scan-assembler-times "sd\tra,\[0-9\]+\\(sp\\)" 1 } } */
+/* { dg-final { scan-assembler-times "sd\ts0,\[0-9\]+\\(sp\\)" 1 } } */
diff --git a/gcc/testsuite/gcc.target/riscv/omit-frame-pointer-3.c
b/gcc/testsuite/gcc.target/riscv/omit-frame-pointer-3.c
new file mode 100644
index 00000000000..b4d7d6f4f0d
--- /dev/null
+++ b/gcc/testsuite/gcc.target/riscv/omit-frame-pointer-3.c
@@ -0,0 +1,7 @@
+/* { dg-do compile } */
+/* { dg-options "-march=rv64gc -mabi=lp64 -O2 -fomit-frame-pointer
-mno-omit-leaf-frame-pointer -fno-inline" } */
+
+#include "omit-frame-pointer-test.c"
+
+/* { dg-final { scan-assembler-times "sd\tra,\[0-9\]+\\(sp\\)" 1 } } */
+/* { dg-final { scan-assembler-not "sd\ts0,\[0-9\]+\\(sp\\)"} } */
diff --git a/gcc/testsuite/gcc.target/riscv/omit-frame-pointer-4.c
b/gcc/testsuite/gcc.target/riscv/omit-frame-pointer-4.c
new file mode 100644
index 00000000000..5a5b540ef4e
--- /dev/null
+++ b/gcc/testsuite/gcc.target/riscv/omit-frame-pointer-4.c
@@ -0,0 +1,7 @@
+/* { dg-do compile } */
+/* { dg-options "-march=rv64gc -mabi=lp64 -O2 -fomit-frame-pointer
-momit-leaf-frame-pointer -fno-inline" } */
+
+#include "omit-frame-pointer-test.c"
+
+/* { dg-final { scan-assembler-times "sd\tra,\[0-9\]+\\(sp\\)" 1 } } */
+/* { dg-final { scan-assembler-not "sd\ts0,\[0-9\]+\\(sp\\)"} } */
diff --git a/gcc/testsuite/gcc.target/riscv/omit-frame-pointer-test.c
b/gcc/testsuite/gcc.target/riscv/omit-frame-pointer-test.c
new file mode 100644
index 00000000000..cf19f001e29
--- /dev/null
+++ b/gcc/testsuite/gcc.target/riscv/omit-frame-pointer-test.c
@@ -0,0 +1,13 @@
+int inc(int n)
+{
+ return n + 1;
+}
+
+
+int bar(void)
+{
+ int n = 100;
+ n = inc(n);
+ n = inc(n) + 100;
+ return n;
+}
--
2.40.1
