diff mbox series

[APX,PPX] Support Intel APX PPX

Message ID 20231117072548.3543202-1-hongyu.wang@intel.com
State Unresolved
Headers
Series [APX,PPX] Support Intel APX PPX |

Checks

Context Check Description
snail/gcc-patch-check warning Git am fail log

Commit Message

Hongyu Wang Nov. 17, 2023, 7:25 a.m. UTC 
  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 mbox series

Patch

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)
+{
+  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));
+
+  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);
+
+  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));
+      RTX_FRAME_RELATED_P (insn) = 1;
+      rtx dwarf = NULL_RTX;
+      dwarf = alloc_reg_note (REG_CFA_RESTORE, reg, dwarf);
+      REG_NOTES (insn) = dwarf;
+    }
+  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")])
+
+(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));