> I think you just need to add an extra (unspec [(const_int 0)]
> UNSPEC_PPX) to origin push_di pattern, then no need for particular
> handling of dwarf and cfa stuffs.
> Ditto for popp and push2p and pop2p.
Yes, such change also worked and no cfa adjustment required then,
thanks for the suggestion.
Updated patch with just 1 new UNSPEC and removed cfa handling.
Hongtao Liu <crazy...@gmail.com> 于2023年11月20日周一 14:46写道：
>
> On Fri, Nov 17, 2023 at 3:26 PM Hongyu Wang <hongyu.w...@intel.com> wrote:
> >
> > Intel APX PPX feature has been released in [1].
> >
> > PPX stands for Push-Pop Acceleration. PUSH/PUSH2 and its corresponding POP
> > can be marked with a 1-bit hint to indicate that the POP reads the
> > value written by the PUSH from the stack. The processor tracks these marked
> > instructions internally and fast-forwards register data between
> > matching PUSH and POP instructions, without going through memory or
> > through the training loop of the Fast Store Forwarding Predictor (FSFP).
> > This feature can also be adopted to PUSH2/POP2.
> >
> > For GCC, we emit explicit suffix 'p' (paired) to indicate the push/pop
> > pair are marked with PPX hint. To separate form original push/pop, we
> > use UNSPEC to restrict the PPX related patterns. So for pushp/popp, the
> > cfi is manually adjusted for the UNSPEC PPX insns.
> >
> > In the first implementation we only emit them under prologue/epilogue
> > when saving/restoring callee-saved registers to make sure push/pop are
> > paired. So an extra flag was added to check if PPX insns can be emitted
> > for those register save/restore interfaces.
> >
> > The PPX hint is purely a performance hint. If the 'p' suffix is not
> > emitted for paired push/pop, the PPX optimization will be disabled,
> > while program sematic will not be affected at all.
> >
> > Bootstrapped/regtest on x86-64-pc-linux-gnu{-m32,}.
> >
> > Ok for master?
> >
> > [1].https://www.intel.com/content/www/us/en/developer/articles/technical/advanced-performance-extensions-apx.ht
> >
> > gcc/ChangeLog:
> >
> > * config/i386/i386-opts.h (enum apx_features): Add apx_ppx, add
> > it to apx_all.
> > * config/i386/i386.cc (ix86_emit_restore_reg_using_pop): Add
> > ppx_p parameter for function declaration.
> > (gen_push2): Add ppx_p parameter, emit push2p if ppx_p is true.
> > (ix86_emit_restore_reg_using_pop2): Likewise for pop2p.
> > (gen_pushp): New function to emit pushp and adjust cfi.
> > (ix86_emit_save_regs): Emit pushp/push2p under TARGET_APX_PPX.
> > (ix86_emit_restore_reg_using_pop): Add ppx_p, emit popp insn
> > and adjust cfi when ppx_p is ture.
> > (ix86_emit_restore_reg_using_pop2): Add ppx_p and parse to its
> > callee.
> > (ix86_emit_restore_regs_using_pop2): Likewise.
> > (ix86_expand_epilogue): Parse TARGET_APX_PPX to
> > ix86_emit_restore_reg_using_pop.
> > * config/i386/i386.h (TARGET_APX_PPX): New.
> > * config/i386/i386.md (UNSPEC_APXPUSHP): New unspec.
> > (UNSPEC_APXPOPP): Likewise.
> > (UNSPEC_APXPUSH2P): Likewise.
> > (UNSPEC_APXPOP2P_LOW): Likewise.
> > (UNSPEC_APXPOP2P_HIGH): Likewise.
> > (pushp_di): New define_insn.
> > (popp_di): Likewise.
> > (push2p_di): Likewise.
> > (pop2p_di): Likewise.
> > * config/i386/i386.opt: Add apx_ppx enum.
> >
> > gcc/testsuite/ChangeLog:
> >
> > * gcc.target/i386/apx-interrupt-1.c: Adjust option to restrict them
> > under certain subfeatures.
> > * gcc.target/i386/apx-push2pop2-1.c: Likewise.
> > * gcc.target/i386/apx-push2pop2_force_drap-1.c: Likewise.
> > * gcc.target/i386/apx-push2pop2_interrupt-1.c: Likewise.
> > * gcc.target/i386/apx-ppx-1.c: New test.
> > ---
> > gcc/config/i386/i386-opts.h | 3 +-
> > gcc/config/i386/i386.cc | 113 ++++++++++++++----
> > gcc/config/i386/i386.h | 1 +
> > gcc/config/i386/i386.md | 47 +++++++-
> > gcc/config/i386/i386.opt | 3 +
> > .../gcc.target/i386/apx-interrupt-1.c | 2 +-
> > gcc/testsuite/gcc.target/i386/apx-ppx-1.c | 9 ++
> > .../gcc.target/i386/apx-push2pop2-1.c | 2 +-
> > .../i386/apx-push2pop2_force_drap-1.c | 2 +-
> > .../i386/apx-push2pop2_interrupt-1.c | 2 +-
> > 10 files changed, 158 insertions(+), 26 deletions(-)
> > create mode 100644 gcc/testsuite/gcc.target/i386/apx-ppx-1.c
> >
> > diff --git a/gcc/config/i386/i386-opts.h b/gcc/config/i386/i386-opts.h
> > index 2ec76a16bce..4d293edb399 100644
> > --- a/gcc/config/i386/i386-opts.h
> > +++ b/gcc/config/i386/i386-opts.h
> > @@ -139,7 +139,8 @@ enum apx_features {
> > apx_egpr = 1 << 0,
> > apx_push2pop2 = 1 << 1,
> > apx_ndd = 1 << 2,
> > - apx_all = apx_egpr | apx_push2pop2 | apx_ndd,
> > + apx_ppx = 1 << 3,
> > + apx_all = apx_egpr | apx_push2pop2 | apx_ndd | apx_ppx,
> > };
> >
> > #endif
> > diff --git a/gcc/config/i386/i386.cc b/gcc/config/i386/i386.cc
> > index 683ac643bc8..df2fc236c0a 100644
> > --- a/gcc/config/i386/i386.cc
> > +++ b/gcc/config/i386/i386.cc
> > @@ -105,7 +105,7 @@ along with GCC; see the file COPYING3. If not see
> > static rtx legitimize_dllimport_symbol (rtx, bool);
> > static rtx legitimize_pe_coff_extern_decl (rtx, bool);
> > static void ix86_print_operand_address_as (FILE *, rtx, addr_space_t,
> > bool);
> > -static void ix86_emit_restore_reg_using_pop (rtx);
> > +static void ix86_emit_restore_reg_using_pop (rtx, bool = false);
> >
> >
> > #ifndef CHECK_STACK_LIMIT
> > @@ -6512,7 +6512,7 @@ gen_popfl (void)
> >
> > /* Generate a "push2" pattern for input ARG. */
> > rtx
> > -gen_push2 (rtx mem, rtx reg1, rtx reg2)
> > +gen_push2 (rtx mem, rtx reg1, rtx reg2, bool ppx_p = false)
> > {
> > struct machine_function *m = cfun->machine;
> > const int offset = UNITS_PER_WORD * 2;
> > @@ -6527,9 +6527,49 @@ gen_push2 (rtx mem, rtx reg1, rtx reg2)
> > if (REG_P (reg2) && GET_MODE (reg2) != word_mode)
> > reg2 = gen_rtx_REG (word_mode, REGNO (reg2));
> >
> > - return gen_push2_di (mem, reg1, reg2);
> > + return ppx_p ? gen_push2p_di (mem, reg1, reg2):
> > + gen_push2_di (mem, reg1, reg2);
> > }
> >
> > +/* Generate a "pushp" insn for input ARG, and set reg notes. */
> > +rtx_insn *
> > +gen_pushp (rtx arg)
> > +{
> Can we just overload gen_push with an new arg bool ppx just like we
> did for push2/pop2.
> > + struct machine_function *m = cfun->machine;
> > +
> > + if (m->fs.cfa_reg == stack_pointer_rtx)
> > + m->fs.cfa_offset += UNITS_PER_WORD;
> > + m->fs.sp_offset += UNITS_PER_WORD;
> > +
> > + if (REG_P (arg) && GET_MODE (arg) != word_mode)
> > + arg = gen_rtx_REG (word_mode, REGNO (arg));
> > +
> > + rtx pat = gen_rtx_MEM (word_mode,
> > + gen_rtx_PRE_DEC (Pmode,
> > + stack_pointer_rtx));
> > + rtx_insn *insn = emit_insn (gen_pushp_di (pat, arg));
> > +
> Why do we need ..
> > + rtx dwarf = gen_rtx_SEQUENCE (VOIDmode, rtvec_alloc (2));
> > +
> > + rtx dwarf_reg = gen_rtx_REG (word_mode,
> > + REGNO (arg));
> > + rtx tmp = gen_rtx_SET (gen_frame_mem (DImode,
> > + stack_pointer_rtx),
> > + dwarf_reg);
> > + RTX_FRAME_RELATED_P (tmp) = 1;
> > + XVECEXP (dwarf, 0, 1) = tmp;
> > + rtx sp_tmp = gen_rtx_SET (stack_pointer_rtx,
> > + plus_constant (Pmode,
> > + stack_pointer_rtx,
> > + -UNITS_PER_WORD));
> > + RTX_FRAME_RELATED_P (sp_tmp) = 1;
> > + XVECEXP (dwarf, 0, 0) = sp_tmp;
> > + add_reg_note (insn, REG_FRAME_RELATED_EXPR, dwarf);
> this. I assume pushp should be different from push only by ppx hint, not
> dwarf.
> > +
> > + return insn;
> > +}
> > +
> > +
> > /* Return >= 0 if there is an unused call-clobbered register available
> > for the entire function. */
> >
> > @@ -7369,7 +7409,10 @@ ix86_emit_save_regs (void)
> > for (regno = FIRST_PSEUDO_REGISTER - 1; regno >= 0; regno--)
> > if (GENERAL_REGNO_P (regno) && ix86_save_reg (regno, true, true))
> > {
> > - insn = emit_insn (gen_push (gen_rtx_REG (word_mode, regno)));
> > + if (TARGET_APX_PPX)
> > + insn = gen_pushp (gen_rtx_REG (word_mode, regno));
> > + else
> > + insn = emit_insn (gen_push (gen_rtx_REG (word_mode, regno)));
> > RTX_FRAME_RELATED_P (insn) = 1;
> > }
> > }
> > @@ -7399,7 +7442,8 @@ ix86_emit_save_regs (void)
> > gen_rtx_REG (word_mode,
> >
> > regno_list[0]),
> > gen_rtx_REG (word_mode,
> > -
> > regno_list[1])));
> > +
> > regno_list[1]),
> > + TARGET_APX_PPX));
> > RTX_FRAME_RELATED_P (insn) = 1;
> > rtx dwarf = gen_rtx_SEQUENCE (VOIDmode, rtvec_alloc
> > (3));
> >
> > @@ -7431,15 +7475,21 @@ ix86_emit_save_regs (void)
> > }
> > else
> > {
> > - insn = emit_insn (gen_push (gen_rtx_REG (word_mode,
> > regno)));
> > + if (TARGET_APX_PPX)
> > + insn = gen_pushp (gen_rtx_REG (word_mode, regno));
> > + else
> > + insn = emit_insn (gen_push (gen_rtx_REG (word_mode,
> > regno)));
> > RTX_FRAME_RELATED_P (insn) = 1;
> > aligned = true;
> > }
> > }
> > if (loaded_regnum == 1)
> > {
> > - insn = emit_insn (gen_push (gen_rtx_REG (word_mode,
> > - regno_list[0])));
> > + if (TARGET_APX_PPX)
> > + insn = gen_pushp (gen_rtx_REG (word_mode, regno_list[0]));
> > + else
> > + insn = emit_insn (gen_push (gen_rtx_REG (word_mode,
> > + regno_list[0])));
> > RTX_FRAME_RELATED_P (insn) = 1;
> > }
> > }
> > @@ -9268,15 +9318,30 @@ ix86_expand_prologue (void)
> > emit_insn (gen_prologue_use (stack_pointer_rtx));
> > }
> >
> > -/* Emit code to restore REG using a POP insn. */
> > +/* Emit code to restore REG using a POP or POPP insn. */
> >
> > static void
> > -ix86_emit_restore_reg_using_pop (rtx reg)
> > +ix86_emit_restore_reg_using_pop (rtx reg, bool ppx_p)
> > {
> > struct machine_function *m = cfun->machine;
> > - rtx_insn *insn = emit_insn (gen_pop (reg));
> > + rtx_insn *insn;
> >
> > - ix86_add_cfa_restore_note (insn, reg, m->fs.sp_offset);
> > + if (ppx_p)
> > + {
> > + rtx stack = gen_rtx_MEM (word_mode,
> > + gen_rtx_POST_INC (Pmode,
> > + stack_pointer_rtx));
> > + insn = emit_insn (gen_popp_di (reg, stack));
> Diddo for ..
> > + RTX_FRAME_RELATED_P (insn) = 1;
> > + rtx dwarf = NULL_RTX;
> > + dwarf = alloc_reg_note (REG_CFA_RESTORE, reg, dwarf);
> > + REG_NOTES (insn) = dwarf;
> .. this, why it's different from pop regarding cfa?
> > + }
> > + else
> > + {
> > + insn = emit_insn (gen_pop (reg));
> > + ix86_add_cfa_restore_note (insn, reg, m->fs.sp_offset);
> > + }
> > m->fs.sp_offset -= UNITS_PER_WORD;
> >
> > if (m->fs.cfa_reg == crtl->drap_reg
> > @@ -9328,14 +9393,19 @@ ix86_emit_restore_reg_using_pop (rtx reg)
> >
> > /* Emit code to restore REG using a POP2 insn. */
> > static void
> > -ix86_emit_restore_reg_using_pop2 (rtx reg1, rtx reg2)
> > +ix86_emit_restore_reg_using_pop2 (rtx reg1, rtx reg2, bool ppx_p = false)
> > {
> > struct machine_function *m = cfun->machine;
> > const int offset = UNITS_PER_WORD * 2;
> > + rtx_insn *insn;
> >
> > rtx mem = gen_rtx_MEM (TImode, gen_rtx_POST_INC (Pmode,
> > stack_pointer_rtx));
> > - rtx_insn *insn = emit_insn (gen_pop2_di (reg1, mem, reg2));
> > +
> > + if (ppx_p)
> > + insn = emit_insn (gen_pop2p_di (reg1, mem, reg2));
> > + else
> > + insn = emit_insn (gen_pop2_di (reg1, mem, reg2));
> >
> > RTX_FRAME_RELATED_P (insn) = 1;
> >
> > @@ -9397,13 +9467,13 @@ ix86_emit_restore_reg_using_pop2 (rtx reg1, rtx
> > reg2)
> > /* Emit code to restore saved registers using POP insns. */
> >
> > static void
> > -ix86_emit_restore_regs_using_pop (void)
> > +ix86_emit_restore_regs_using_pop (bool ppx_p)
> > {
> > unsigned int regno;
> >
> > for (regno = 0; regno < FIRST_PSEUDO_REGISTER; regno++)
> > if (GENERAL_REGNO_P (regno) && ix86_save_reg (regno, false, true))
> > - ix86_emit_restore_reg_using_pop (gen_rtx_REG (word_mode, regno));
> > + ix86_emit_restore_reg_using_pop (gen_rtx_REG (word_mode, regno),
> > ppx_p);
> > }
> >
> > /* Emit code to restore saved registers using POP2 insns. */
> > @@ -9432,20 +9502,23 @@ ix86_emit_restore_regs_using_pop2 (void)
> > ix86_emit_restore_reg_using_pop2 (gen_rtx_REG (word_mode,
> >
> > regno_list[0]),
> > gen_rtx_REG (word_mode,
> > -
> > regno_list[1]));
> > +
> > regno_list[1]),
> > + TARGET_APX_PPX);
> > loaded_regnum = 0;
> > regno_list[0] = regno_list[1] = -1;
> > }
> > }
> > else
> > {
> > - ix86_emit_restore_reg_using_pop (gen_rtx_REG (word_mode,
> > regno));
> > + ix86_emit_restore_reg_using_pop (gen_rtx_REG (word_mode, regno),
> > + TARGET_APX_PPX);
> > aligned = true;
> > }
> > }
> >
> > if (loaded_regnum == 1)
> > - ix86_emit_restore_reg_using_pop (gen_rtx_REG (word_mode,
> > regno_list[0]));
> > + ix86_emit_restore_reg_using_pop (gen_rtx_REG (word_mode,
> > regno_list[0]),
> > + TARGET_APX_PPX);
> > }
> >
> > /* Emit code and notes for the LEAVE instruction. If insn is non-null,
> > @@ -9990,7 +10063,7 @@ ix86_expand_epilogue (int style)
> > if (TARGET_APX_PUSH2POP2 && m->func_type == TYPE_NORMAL)
> > ix86_emit_restore_regs_using_pop2 ();
> > else
> > - ix86_emit_restore_regs_using_pop ();
> > + ix86_emit_restore_regs_using_pop (TARGET_APX_PPX);
> > }
> >
> > /* If we used a stack pointer and haven't already got rid of it,
> > diff --git a/gcc/config/i386/i386.h b/gcc/config/i386/i386.h
> > index 037074758ea..227217a8712 100644
> > --- a/gcc/config/i386/i386.h
> > +++ b/gcc/config/i386/i386.h
> > @@ -54,6 +54,7 @@ see the files COPYING3 and COPYING.RUNTIME respectively.
> > If not, see
> > #define TARGET_APX_EGPR (ix86_apx_features & apx_egpr)
> > #define TARGET_APX_PUSH2POP2 (ix86_apx_features & apx_push2pop2)
> > #define TARGET_APX_NDD (ix86_apx_features & apx_ndd)
> > +#define TARGET_APX_PPX (ix86_apx_features & apx_ppx)
> >
> > #include "config/vxworks-dummy.h"
> >
> > diff --git a/gcc/config/i386/i386.md b/gcc/config/i386/i386.md
> > index 1b5a794b9e5..8cce4c11e35 100644
> > --- a/gcc/config/i386/i386.md
> > +++ b/gcc/config/i386/i386.md
> > @@ -210,10 +210,17 @@ (define_c_enum "unspec" [
> > ;; For insn_callee_abi:
> > UNSPEC_CALLEE_ABI
> >
> > - ;; For PUSH2/POP2 support
> > + ;; For APX PUSH2/POP2 support
> > UNSPEC_APXPUSH2
> > UNSPEC_APXPOP2_LOW
> > UNSPEC_APXPOP2_HIGH
> > +
> > + ;; For APX PPX support
> > + UNSPEC_APXPUSHP
> > + UNSPEC_APXPOPP
> > + UNSPEC_APXPUSH2P
> > + UNSPEC_APXPOP2P_LOW
> > + UNSPEC_APXPOP2P_HIGH
> > ])
> >
> > (define_c_enum "unspecv" [
> > @@ -3785,6 +3792,44 @@ (define_insn "pop2_di"
> > [(set_attr "mode" "TI")
> > (set_attr "prefix" "evex")])
> >
> > +(define_insn "pushp_di"
> > + [(set (match_operand:DI 0 "push_operand" "=<")
> > + (unspec: DI [(match_operand:DI 1 "register_operand" "r")]
> > + UNSPEC_APXPUSHP))]
> > + "TARGET_64BIT"
> > + "pushp\t%1"
> > + [(set_attr "mode" "DI")])
> I think you just need to add an extra (unspec [(const_int 0)]
> UNSPEC_PPX) to origin push_di pattern, then no need for particular
> handling of dwarf and cfa stuffs.
> Ditto for popp and push2p and pop2p.
> > +
> > +(define_insn "popp_di"
> > + [(set (match_operand:DI 0 "nonimmediate_operand" "=r")
> > + (unspec:DI [(match_operand:DI 1 "pop_operand" ">")]
> > + UNSPEC_APXPOPP))]
> > + "TARGET_APX_PPX"
> > + "popp\t%0"
> > + [(set_attr "mode" "DI")])
> > +
> > +(define_insn "push2p_di"
> > + [(set (match_operand:TI 0 "push_operand" "=<")
> > + (unspec:TI [(match_operand:DI 1 "register_operand" "r")
> > + (match_operand:DI 2 "register_operand" "r")]
> > + UNSPEC_APXPUSH2P))]
> > + "TARGET_APX_PUSH2POP2 && TARGET_APX_PPX"
> > + "push2p\t%1, %2"
> > + [(set_attr "mode" "TI")
> > + (set_attr "type" "multi")
> > + (set_attr "prefix" "evex")])
> > +
> > +(define_insn "pop2p_di"
> > + [(parallel [(set (match_operand:DI 0 "register_operand" "=r")
> > + (unspec:DI [(match_operand:TI 1 "pop_operand" ">")]
> > + UNSPEC_APXPOP2P_LOW))
> > + (set (match_operand:DI 2 "register_operand" "=r")
> > + (unspec:DI [(const_int 0)] UNSPEC_APXPOP2P_HIGH))])]
> > + "TARGET_APX_PUSH2POP2 && TARGET_APX_PPX"
> > + "pop2p\t%0, %2"
> > + [(set_attr "mode" "TI")
> > + (set_attr "prefix" "evex")])
> > +
> > (define_insn "*pushsf_rex64"
> > [(set (match_operand:SF 0 "push_operand" "=X,X,X")
> > (match_operand:SF 1 "nonmemory_no_elim_operand" "f,rF,v"))]
> > diff --git a/gcc/config/i386/i386.opt b/gcc/config/i386/i386.opt
> > index 0c3b8f4b621..ee8898e3abb 100644
> > --- a/gcc/config/i386/i386.opt
> > +++ b/gcc/config/i386/i386.opt
> > @@ -1333,6 +1333,9 @@ Enum(apx_features) String(push2pop2)
> > Value(apx_push2pop2) Set(3)
> > EnumValue
> > Enum(apx_features) String(ndd) Value(apx_ndd) Set(4)
> >
> > +EnumValue
> > +Enum(apx_features) String(ppx) Value(apx_ppx) Set(5)
> > +
> > EnumValue
> > Enum(apx_features) String(all) Value(apx_all) Set(1)
> >
> > diff --git a/gcc/testsuite/gcc.target/i386/apx-interrupt-1.c
> > b/gcc/testsuite/gcc.target/i386/apx-interrupt-1.c
> > index 5f732d3e316..ffcb8fce71c 100644
> > --- a/gcc/testsuite/gcc.target/i386/apx-interrupt-1.c
> > +++ b/gcc/testsuite/gcc.target/i386/apx-interrupt-1.c
> > @@ -1,5 +1,5 @@
> > /* { dg-do compile { target { ! ia32 } } } */
> > -/* { dg-options "-mapxf -m64 -O2 -mgeneral-regs-only -mno-cld
> > -mno-push-args -maccumulate-outgoing-args" } */
> > +/* { dg-options "-mapx-features=egpr -m64 -O2 -mgeneral-regs-only -mno-cld
> > -mno-push-args -maccumulate-outgoing-args" } */
> > /* { dg-skip-if "does not emit .cfi_xxx" "*-*-darwin*" } */
> >
> > extern void foo (void *) __attribute__ ((interrupt));
> > diff --git a/gcc/testsuite/gcc.target/i386/apx-ppx-1.c
> > b/gcc/testsuite/gcc.target/i386/apx-ppx-1.c
> > new file mode 100644
> > index 00000000000..e9a595381e3
> > --- /dev/null
> > +++ b/gcc/testsuite/gcc.target/i386/apx-ppx-1.c
> > @@ -0,0 +1,9 @@
> > +/* { dg-do compile { target { ! ia32 } } } */
> > +/* { dg-options "-O2 -mapx-features=egpr,push2pop2,ppx" } */
> > +
> > +#include "apx-push2pop2-1.c"
> > +
> > +/* { dg-final { scan-assembler "pushp" } } */
> > +/* { dg-final { scan-assembler "popp" } } */
> > +/* { dg-final { scan-assembler "push2p" } } */
> > +/* { dg-final { scan-assembler "pop2p" } } */
> > diff --git a/gcc/testsuite/gcc.target/i386/apx-push2pop2-1.c
> > b/gcc/testsuite/gcc.target/i386/apx-push2pop2-1.c
> > index 089941d3726..c53112758a5 100644
> > --- a/gcc/testsuite/gcc.target/i386/apx-push2pop2-1.c
> > +++ b/gcc/testsuite/gcc.target/i386/apx-push2pop2-1.c
> > @@ -1,5 +1,5 @@
> > /* { dg-do compile { target { ! ia32 } } } */
> > -/* { dg-options "-O2 -mapxf" } */
> > +/* { dg-options "-O2 -mapx-features=push2pop2" } */
> > /* { dg-skip-if "does not emit .cfi_xxx" "*-*-darwin*" } */
> >
> > extern int bar (int);
> > diff --git a/gcc/testsuite/gcc.target/i386/apx-push2pop2_force_drap-1.c
> > b/gcc/testsuite/gcc.target/i386/apx-push2pop2_force_drap-1.c
> > index 656ca91391a..022113bb1e2 100644
> > --- a/gcc/testsuite/gcc.target/i386/apx-push2pop2_force_drap-1.c
> > +++ b/gcc/testsuite/gcc.target/i386/apx-push2pop2_force_drap-1.c
> > @@ -1,5 +1,5 @@
> > /* { dg-do compile { target { ! ia32 } } } */
> > -/* { dg-options "-O2 -mapxf -mforce-drap" } */
> > +/* { dg-options "-O2 -mapx-features=push2pop2 -mforce-drap" } */
> > /* { dg-skip-if "does not emit .cfi_xxx" "*-*-darwin*" } */
> >
> > #include "apx-push2pop2-1.c"
> > diff --git a/gcc/testsuite/gcc.target/i386/apx-push2pop2_interrupt-1.c
> > b/gcc/testsuite/gcc.target/i386/apx-push2pop2_interrupt-1.c
> > index 747f7aaf191..a5b46893208 100644
> > --- a/gcc/testsuite/gcc.target/i386/apx-push2pop2_interrupt-1.c
> > +++ b/gcc/testsuite/gcc.target/i386/apx-push2pop2_interrupt-1.c
> > @@ -1,5 +1,5 @@
> > /* { dg-do compile { target { ! ia32 } } } */
> > -/* { dg-options "-O2 -mapxf -mgeneral-regs-only -mno-cld -mno-push-args
> > -maccumulate-outgoing-args" } */
> > +/* { dg-options "-O2 -mapx-features=egpr,push2pop2 -mgeneral-regs-only
> > -mno-cld -mno-push-args -maccumulate-outgoing-args" } */
> >
> > extern void foo (void *) __attribute__ ((interrupt));
> >
> > --
> > 2.31.1
> >
>
>
> --
> BR,
> Hongtao
From d9c4a1cf3dd1d9027c47e3670fe89f0087f7b0f9 Mon Sep 17 00:00:00 2001
From: Hongyu Wang <hongyu.w...@intel.com>
Date: Thu, 16 Nov 2023 15:18:07 +0800
Subject: [PATCH] [APX PPX] Support Intel APX PPX
PPX stands for Push-Pop Acceleration. PUSH/PUSH2 and its corresponding POP
can be marked with a 1-bit hint to indicate that the POP reads the
value written by the PUSH from the stack. The processor tracks these marked
instructions internally and fast-forwards register data between
matching PUSH and POP instructions, without going through memory or
through the training loop of the Fast Store Forwarding Predictor (FSFP).
This feature can also be adopted to PUSH2/POP2.
For GCC, we emit explicit suffix 'p' (paired) to indicate the push/pop
pair are marked with PPX hint. To separate form original push/pop, we
add an UNSPEC on top of those PUSH/POP patterns.
In the first implementation we only emit them under prologue/epilogue
when saving/restoring callee-saved registers to make sure push/pop are
paired. So an extra flag was added to check if PPX insns can be emitted
for those register save/restore interfaces.
The PPX hint is purely a performance hint. If the 'p' suffix is not
emitted for paired push/pop, the PPX optimization will be disabled,
while program sematic will not be affected at all.
gcc/ChangeLog:
* config/i386/i386-expand.h (gen_push): Add default bool
parameter.
(gen_pop): Likewise.
* config/i386/i386-opts.h (enum apx_features): Add apx_ppx, add
it to apx_all.
* config/i386/i386.cc (ix86_emit_restore_reg_using_pop): Add
ppx_p parameter for function declaration.
(gen_push2): Add ppx_p parameter, emit push2p if ppx_p is true.
(gen_push): Likewise.
(ix86_emit_restore_reg_using_pop2): Likewise for pop2p.
(ix86_emit_save_regs): Emit pushp/push2p under TARGET_APX_PPX.
(ix86_emit_restore_reg_using_pop): Add ppx_p, emit popp insn
and adjust cfi when ppx_p is ture.
(ix86_emit_restore_reg_using_pop2): Add ppx_p and parse to its
callee.
(ix86_emit_restore_regs_using_pop2): Likewise.
(ix86_expand_epilogue): Parse TARGET_APX_PPX to
ix86_emit_restore_reg_using_pop.
* config/i386/i386.h (TARGET_APX_PPX): New.
* config/i386/i386.md (UNSPEC_APX_PPX): New unspec.
(pushp_di): New define_insn.
(popp_di): Likewise.
(push2p_di): Likewise.
(pop2p_di): Likewise.
* config/i386/i386.opt: Add apx_ppx enum.
gcc/testsuite/ChangeLog:
* gcc.target/i386/apx-interrupt-1.c: Adjust option to restrict them
under certain subfeatures.
* gcc.target/i386/apx-push2pop2-1.c: Likewise.
* gcc.target/i386/apx-push2pop2_force_drap-1.c: Likewise.
* gcc.target/i386/apx-push2pop2_interrupt-1.c: Likewise.
* gcc.target/i386/apx-ppx-1.c: New test.
---
gcc/config/i386/i386-expand.h | 4 +-
gcc/config/i386/i386-opts.h | 3 +-
gcc/config/i386/i386.cc | 70 +++++++++++--------
gcc/config/i386/i386.h | 1 +
gcc/config/i386/i386.md | 45 +++++++++++-
gcc/config/i386/i386.opt | 3 +
.../gcc.target/i386/apx-interrupt-1.c | 2 +-
gcc/testsuite/gcc.target/i386/apx-ppx-1.c | 9 +++
.../gcc.target/i386/apx-push2pop2-1.c | 2 +-
.../i386/apx-push2pop2_force_drap-1.c | 2 +-
.../i386/apx-push2pop2_interrupt-1.c | 2 +-
11 files changed, 107 insertions(+), 36 deletions(-)
create mode 100644 gcc/testsuite/gcc.target/i386/apx-ppx-1.c
diff --git a/gcc/config/i386/i386-expand.h b/gcc/config/i386/i386-expand.h
index 1ea789c4c3a..997cb7db059 100644
--- a/gcc/config/i386/i386-expand.h
+++ b/gcc/config/i386/i386-expand.h
@@ -44,9 +44,9 @@ void ix86_emit_binop (enum rtx_code code, machine_mode mode, rtx dst, rtx src);
enum calling_abi ix86_function_abi (const_tree fndecl);
bool ix86_function_ms_hook_prologue (const_tree fn);
void warn_once_call_ms2sysv_xlogues (const char *feature);
-rtx gen_push (rtx arg);
+rtx gen_push (rtx arg, bool = false);
rtx gen_pushfl (void);
-rtx gen_pop (rtx arg);
+rtx gen_pop (rtx arg, bool = false);
rtx gen_popfl (void);
rtx ix86_expand_builtin (tree exp, rtx target, rtx subtarget,
machine_mode mode, int ignore);
diff --git a/gcc/config/i386/i386-opts.h b/gcc/config/i386/i386-opts.h
index 2ec76a16bce..4d293edb399 100644
--- a/gcc/config/i386/i386-opts.h
+++ b/gcc/config/i386/i386-opts.h
@@ -139,7 +139,8 @@ enum apx_features {
apx_egpr = 1 << 0,
apx_push2pop2 = 1 << 1,
apx_ndd = 1 << 2,
- apx_all = apx_egpr | apx_push2pop2 | apx_ndd,
+ apx_ppx = 1 << 3,
+ apx_all = apx_egpr | apx_push2pop2 | apx_ndd | apx_ppx,
};
#endif
diff --git a/gcc/config/i386/i386.cc b/gcc/config/i386/i386.cc
index 683ac643bc8..bd340582a33 100644
--- a/gcc/config/i386/i386.cc
+++ b/gcc/config/i386/i386.cc
@@ -105,7 +105,7 @@ along with GCC; see the file COPYING3. If not see
static rtx legitimize_dllimport_symbol (rtx, bool);
static rtx legitimize_pe_coff_extern_decl (rtx, bool);
static void ix86_print_operand_address_as (FILE *, rtx, addr_space_t, bool);
-static void ix86_emit_restore_reg_using_pop (rtx);
+static void ix86_emit_restore_reg_using_pop (rtx, bool = false);
#ifndef CHECK_STACK_LIMIT
@@ -6448,7 +6448,7 @@ output_set_got (rtx dest, rtx label)
/* Generate an "push" pattern for input ARG. */
rtx
-gen_push (rtx arg)
+gen_push (rtx arg, bool ppx_p)
{
struct machine_function *m = cfun->machine;
@@ -6459,10 +6459,10 @@ gen_push (rtx arg)
if (REG_P (arg) && GET_MODE (arg) != word_mode)
arg = gen_rtx_REG (word_mode, REGNO (arg));
- return gen_rtx_SET (gen_rtx_MEM (word_mode,
- gen_rtx_PRE_DEC (Pmode,
- stack_pointer_rtx)),
- arg);
+ rtx stack = gen_rtx_MEM (word_mode,
+ gen_rtx_PRE_DEC (Pmode,
+ stack_pointer_rtx));
+ return ppx_p ? gen_pushp_di (stack, arg) : gen_rtx_SET (stack, arg);
}
rtx
@@ -6486,15 +6486,16 @@ gen_pushfl (void)
/* Generate an "pop" pattern for input ARG. */
rtx
-gen_pop (rtx arg)
+gen_pop (rtx arg, bool ppx_p)
{
if (REG_P (arg) && GET_MODE (arg) != word_mode)
arg = gen_rtx_REG (word_mode, REGNO (arg));
- return gen_rtx_SET (arg,
- gen_rtx_MEM (word_mode,
- gen_rtx_POST_INC (Pmode,
- stack_pointer_rtx)));
+ rtx stack = gen_rtx_MEM (word_mode,
+ gen_rtx_POST_INC (Pmode,
+ stack_pointer_rtx));
+
+ return ppx_p ? gen_popp_di (arg, stack) : gen_rtx_SET (arg, stack);
}
rtx
@@ -6512,7 +6513,7 @@ gen_popfl (void)
/* Generate a "push2" pattern for input ARG. */
rtx
-gen_push2 (rtx mem, rtx reg1, rtx reg2)
+gen_push2 (rtx mem, rtx reg1, rtx reg2, bool ppx_p = false)
{
struct machine_function *m = cfun->machine;
const int offset = UNITS_PER_WORD * 2;
@@ -6527,7 +6528,8 @@ gen_push2 (rtx mem, rtx reg1, rtx reg2)
if (REG_P (reg2) && GET_MODE (reg2) != word_mode)
reg2 = gen_rtx_REG (word_mode, REGNO (reg2));
- return gen_push2_di (mem, reg1, reg2);
+ return ppx_p ? gen_push2p_di (mem, reg1, reg2):
+ gen_push2_di (mem, reg1, reg2);
}
/* Return >= 0 if there is an unused call-clobbered register available
@@ -7369,7 +7371,8 @@ ix86_emit_save_regs (void)
for (regno = FIRST_PSEUDO_REGISTER - 1; regno >= 0; regno--)
if (GENERAL_REGNO_P (regno) && ix86_save_reg (regno, true, true))
{
- insn = emit_insn (gen_push (gen_rtx_REG (word_mode, regno)));
+ insn = emit_insn (gen_push (gen_rtx_REG (word_mode, regno),
+ TARGET_APX_PPX));
RTX_FRAME_RELATED_P (insn) = 1;
}
}
@@ -7399,7 +7402,8 @@ ix86_emit_save_regs (void)
gen_rtx_REG (word_mode,
regno_list[0]),
gen_rtx_REG (word_mode,
- regno_list[1])));
+ regno_list[1]),
+ TARGET_APX_PPX));
RTX_FRAME_RELATED_P (insn) = 1;
rtx dwarf = gen_rtx_SEQUENCE (VOIDmode, rtvec_alloc (3));
@@ -7431,7 +7435,8 @@ ix86_emit_save_regs (void)
}
else
{
- insn = emit_insn (gen_push (gen_rtx_REG (word_mode, regno)));
+ insn = emit_insn (gen_push (gen_rtx_REG (word_mode, regno),
+ TARGET_APX_PPX));
RTX_FRAME_RELATED_P (insn) = 1;
aligned = true;
}
@@ -7439,7 +7444,8 @@ ix86_emit_save_regs (void)
if (loaded_regnum == 1)
{
insn = emit_insn (gen_push (gen_rtx_REG (word_mode,
- regno_list[0])));
+ regno_list[0]),
+ TARGET_APX_PPX));
RTX_FRAME_RELATED_P (insn) = 1;
}
}
@@ -9268,13 +9274,13 @@ ix86_expand_prologue (void)
emit_insn (gen_prologue_use (stack_pointer_rtx));
}
-/* Emit code to restore REG using a POP insn. */
+/* Emit code to restore REG using a POP or POPP insn. */
static void
-ix86_emit_restore_reg_using_pop (rtx reg)
+ix86_emit_restore_reg_using_pop (rtx reg, bool ppx_p)
{
struct machine_function *m = cfun->machine;
- rtx_insn *insn = emit_insn (gen_pop (reg));
+ rtx_insn *insn = emit_insn (gen_pop (reg, ppx_p));
ix86_add_cfa_restore_note (insn, reg, m->fs.sp_offset);
m->fs.sp_offset -= UNITS_PER_WORD;
@@ -9328,14 +9334,19 @@ ix86_emit_restore_reg_using_pop (rtx reg)
/* Emit code to restore REG using a POP2 insn. */
static void
-ix86_emit_restore_reg_using_pop2 (rtx reg1, rtx reg2)
+ix86_emit_restore_reg_using_pop2 (rtx reg1, rtx reg2, bool ppx_p = false)
{
struct machine_function *m = cfun->machine;
const int offset = UNITS_PER_WORD * 2;
+ rtx_insn *insn;
rtx mem = gen_rtx_MEM (TImode, gen_rtx_POST_INC (Pmode,
stack_pointer_rtx));
- rtx_insn *insn = emit_insn (gen_pop2_di (reg1, mem, reg2));
+
+ if (ppx_p)
+ insn = emit_insn (gen_pop2p_di (reg1, mem, reg2));
+ else
+ insn = emit_insn (gen_pop2_di (reg1, mem, reg2));
RTX_FRAME_RELATED_P (insn) = 1;
@@ -9397,13 +9408,13 @@ ix86_emit_restore_reg_using_pop2 (rtx reg1, rtx reg2)
/* Emit code to restore saved registers using POP insns. */
static void
-ix86_emit_restore_regs_using_pop (void)
+ix86_emit_restore_regs_using_pop (bool ppx_p)
{
unsigned int regno;
for (regno = 0; regno < FIRST_PSEUDO_REGISTER; regno++)
if (GENERAL_REGNO_P (regno) && ix86_save_reg (regno, false, true))
- ix86_emit_restore_reg_using_pop (gen_rtx_REG (word_mode, regno));
+ ix86_emit_restore_reg_using_pop (gen_rtx_REG (word_mode, regno), ppx_p);
}
/* Emit code to restore saved registers using POP2 insns. */
@@ -9432,20 +9443,23 @@ ix86_emit_restore_regs_using_pop2 (void)
ix86_emit_restore_reg_using_pop2 (gen_rtx_REG (word_mode,
regno_list[0]),
gen_rtx_REG (word_mode,
- regno_list[1]));
+ regno_list[1]),
+ TARGET_APX_PPX);
loaded_regnum = 0;
regno_list[0] = regno_list[1] = -1;
}
}
else
{
- ix86_emit_restore_reg_using_pop (gen_rtx_REG (word_mode, regno));
+ ix86_emit_restore_reg_using_pop (gen_rtx_REG (word_mode, regno),
+ TARGET_APX_PPX);
aligned = true;
}
}
if (loaded_regnum == 1)
- ix86_emit_restore_reg_using_pop (gen_rtx_REG (word_mode, regno_list[0]));
+ ix86_emit_restore_reg_using_pop (gen_rtx_REG (word_mode, regno_list[0]),
+ TARGET_APX_PPX);
}
/* Emit code and notes for the LEAVE instruction. If insn is non-null,
@@ -9990,7 +10004,7 @@ ix86_expand_epilogue (int style)
if (TARGET_APX_PUSH2POP2 && m->func_type == TYPE_NORMAL)
ix86_emit_restore_regs_using_pop2 ();
else
- ix86_emit_restore_regs_using_pop ();
+ ix86_emit_restore_regs_using_pop (TARGET_APX_PPX);
}
/* If we used a stack pointer and haven't already got rid of it,
diff --git a/gcc/config/i386/i386.h b/gcc/config/i386/i386.h
index 037074758ea..227217a8712 100644
--- a/gcc/config/i386/i386.h
+++ b/gcc/config/i386/i386.h
@@ -54,6 +54,7 @@ see the files COPYING3 and COPYING.RUNTIME respectively. If not, see
#define TARGET_APX_EGPR (ix86_apx_features & apx_egpr)
#define TARGET_APX_PUSH2POP2 (ix86_apx_features & apx_push2pop2)
#define TARGET_APX_NDD (ix86_apx_features & apx_ndd)
+#define TARGET_APX_PPX (ix86_apx_features & apx_ppx)
#include "config/vxworks-dummy.h"
diff --git a/gcc/config/i386/i386.md b/gcc/config/i386/i386.md
index 1b5a794b9e5..03e4ddd3037 100644
--- a/gcc/config/i386/i386.md
+++ b/gcc/config/i386/i386.md
@@ -210,10 +210,13 @@ (define_c_enum "unspec" [
;; For insn_callee_abi:
UNSPEC_CALLEE_ABI
- ;; For PUSH2/POP2 support
+ ;; For APX PUSH2/POP2 support
UNSPEC_APXPUSH2
UNSPEC_APXPOP2_LOW
UNSPEC_APXPOP2_HIGH
+
+ ;; For APX PPX support
+ UNSPEC_APX_PPX
])
(define_c_enum "unspecv" [
@@ -3785,6 +3788,46 @@ (define_insn "pop2_di"
[(set_attr "mode" "TI")
(set_attr "prefix" "evex")])
+(define_insn "pushp_di"
+ [(set (match_operand:DI 0 "push_operand" "=<")
+ (match_operand:DI 1 "register_operand" "r"))
+ (unspec:DI [(const_int 0)] UNSPEC_APX_PPX)]
+ "TARGET_64BIT"
+ "pushp\t%1"
+ [(set_attr "mode" "DI")])
+
+(define_insn "popp_di"
+ [(set (match_operand:DI 0 "register_operand" "=r")
+ (match_operand:DI 1 "pop_operand" ">"))
+ (unspec:DI [(const_int 0)] UNSPEC_APX_PPX)]
+ "TARGET_APX_PPX"
+ "popp\t%0"
+ [(set_attr "mode" "DI")])
+
+(define_insn "push2p_di"
+ [(set (match_operand:TI 0 "push_operand" "=<")
+ (unspec:TI [(match_operand:DI 1 "register_operand" "r")
+ (match_operand:DI 2 "register_operand" "r")]
+ UNSPEC_APXPUSH2))
+ (unspec:DI [(const_int 0)] UNSPEC_APX_PPX)]
+ "TARGET_APX_PUSH2POP2 && TARGET_APX_PPX"
+ "push2p\t%1, %2"
+ [(set_attr "mode" "TI")
+ (set_attr "type" "multi")
+ (set_attr "prefix" "evex")])
+
+(define_insn "pop2p_di"
+ [(parallel [(set (match_operand:DI 0 "register_operand" "=r")
+ (unspec:DI [(match_operand:TI 1 "pop_operand" ">")]
+ UNSPEC_APXPOP2_LOW))
+ (set (match_operand:DI 2 "register_operand" "=r")
+ (unspec:DI [(const_int 0)] UNSPEC_APXPOP2_HIGH))
+ (unspec:DI [(const_int 0)] UNSPEC_APX_PPX)])]
+ "TARGET_APX_PUSH2POP2 && TARGET_APX_PPX"
+ "pop2p\t%0, %2"
+ [(set_attr "mode" "TI")
+ (set_attr "prefix" "evex")])
+
(define_insn "*pushsf_rex64"
[(set (match_operand:SF 0 "push_operand" "=X,X,X")
(match_operand:SF 1 "nonmemory_no_elim_operand" "f,rF,v"))]
diff --git a/gcc/config/i386/i386.opt b/gcc/config/i386/i386.opt
index 0c3b8f4b621..ee8898e3abb 100644
--- a/gcc/config/i386/i386.opt
+++ b/gcc/config/i386/i386.opt
@@ -1333,6 +1333,9 @@ Enum(apx_features) String(push2pop2) Value(apx_push2pop2) Set(3)
EnumValue
Enum(apx_features) String(ndd) Value(apx_ndd) Set(4)
+EnumValue
+Enum(apx_features) String(ppx) Value(apx_ppx) Set(5)
+
EnumValue
Enum(apx_features) String(all) Value(apx_all) Set(1)
diff --git a/gcc/testsuite/gcc.target/i386/apx-interrupt-1.c b/gcc/testsuite/gcc.target/i386/apx-interrupt-1.c
index 5f732d3e316..ffcb8fce71c 100644
--- a/gcc/testsuite/gcc.target/i386/apx-interrupt-1.c
+++ b/gcc/testsuite/gcc.target/i386/apx-interrupt-1.c
@@ -1,5 +1,5 @@
/* { dg-do compile { target { ! ia32 } } } */
-/* { dg-options "-mapxf -m64 -O2 -mgeneral-regs-only -mno-cld -mno-push-args -maccumulate-outgoing-args" } */
+/* { dg-options "-mapx-features=egpr -m64 -O2 -mgeneral-regs-only -mno-cld -mno-push-args -maccumulate-outgoing-args" } */
/* { dg-skip-if "does not emit .cfi_xxx" "*-*-darwin*" } */
extern void foo (void *) __attribute__ ((interrupt));
diff --git a/gcc/testsuite/gcc.target/i386/apx-ppx-1.c b/gcc/testsuite/gcc.target/i386/apx-ppx-1.c
new file mode 100644
index 00000000000..e9a595381e3
--- /dev/null
+++ b/gcc/testsuite/gcc.target/i386/apx-ppx-1.c
@@ -0,0 +1,9 @@
+/* { dg-do compile { target { ! ia32 } } } */
+/* { dg-options "-O2 -mapx-features=egpr,push2pop2,ppx" } */
+
+#include "apx-push2pop2-1.c"
+
+/* { dg-final { scan-assembler "pushp" } } */
+/* { dg-final { scan-assembler "popp" } } */
+/* { dg-final { scan-assembler "push2p" } } */
+/* { dg-final { scan-assembler "pop2p" } } */
diff --git a/gcc/testsuite/gcc.target/i386/apx-push2pop2-1.c b/gcc/testsuite/gcc.target/i386/apx-push2pop2-1.c
index 089941d3726..c53112758a5 100644
--- a/gcc/testsuite/gcc.target/i386/apx-push2pop2-1.c
+++ b/gcc/testsuite/gcc.target/i386/apx-push2pop2-1.c
@@ -1,5 +1,5 @@
/* { dg-do compile { target { ! ia32 } } } */
-/* { dg-options "-O2 -mapxf" } */
+/* { dg-options "-O2 -mapx-features=push2pop2" } */
/* { dg-skip-if "does not emit .cfi_xxx" "*-*-darwin*" } */
extern int bar (int);
diff --git a/gcc/testsuite/gcc.target/i386/apx-push2pop2_force_drap-1.c b/gcc/testsuite/gcc.target/i386/apx-push2pop2_force_drap-1.c
index 656ca91391a..022113bb1e2 100644
--- a/gcc/testsuite/gcc.target/i386/apx-push2pop2_force_drap-1.c
+++ b/gcc/testsuite/gcc.target/i386/apx-push2pop2_force_drap-1.c
@@ -1,5 +1,5 @@
/* { dg-do compile { target { ! ia32 } } } */
-/* { dg-options "-O2 -mapxf -mforce-drap" } */
+/* { dg-options "-O2 -mapx-features=push2pop2 -mforce-drap" } */
/* { dg-skip-if "does not emit .cfi_xxx" "*-*-darwin*" } */
#include "apx-push2pop2-1.c"
diff --git a/gcc/testsuite/gcc.target/i386/apx-push2pop2_interrupt-1.c b/gcc/testsuite/gcc.target/i386/apx-push2pop2_interrupt-1.c
index 747f7aaf191..a5b46893208 100644
--- a/gcc/testsuite/gcc.target/i386/apx-push2pop2_interrupt-1.c
+++ b/gcc/testsuite/gcc.target/i386/apx-push2pop2_interrupt-1.c
@@ -1,5 +1,5 @@
/* { dg-do compile { target { ! ia32 } } } */
-/* { dg-options "-O2 -mapxf -mgeneral-regs-only -mno-cld -mno-push-args -maccumulate-outgoing-args" } */
+/* { dg-options "-O2 -mapx-features=egpr,push2pop2 -mgeneral-regs-only -mno-cld -mno-push-args -maccumulate-outgoing-args" } */
extern void foo (void *) __attribute__ ((interrupt));
--
2.31.1
