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 | 34 ++++++++++++++++++- 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, 78 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 706c18416db..caae6168c29 100644 --- a/gcc/config/riscv/riscv.cc +++ b/gcc/config/riscv/riscv.cc @@ -379,6 +379,10 @@ 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; @@ -4948,7 +4952,11 @@ 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. */ @@ -6577,6 +6585,21 @@ riscv_option_override (void) if (flag_pic) riscv_cmodel = CM_PIC; + /* We need to save the fp with ra for non-leaf functions with no fp and ra + for leaf functions while no-omit-frame-pointer with + omit-leaf-frame-pointer. The x_flag_omit_frame_pointer has the first + priority to determine whether the frame pointer is needed. If we do not + override it, the fp and ra will be stored for leaf functions, which is not + our wanted. */ + 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) @@ -7857,6 +7880,12 @@ riscv_preferred_else_value (unsigned, tree, unsigned int nops, tree *ops) return nops == 3 ? ops[2] : ops[0]; } +static bool +riscv_frame_pointer_required (void) +{ + return riscv_save_frame_pointer && !crtl->is_leaf; +} + /* Initialize the GCC target structure. */ #undef TARGET_ASM_ALIGNED_HI_OP #define TARGET_ASM_ALIGNED_HI_OP "\t.half\t" @@ -8161,6 +8190,9 @@ riscv_preferred_else_value (unsigned, tree, unsigned int nops, tree *ops) #undef TARGET_PREFERRED_ELSE_VALUE #define TARGET_PREFERRED_ELSE_VALUE riscv_preferred_else_value +#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 dd062f1c8bd..8e6a94fd01a 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