Add a target calls hook: TARGET_PUSH_ARGUMENT

1. Replace PUSH_ARGS with a target calls hook, TARGET_PUSH_ARGUMENT, which
takes an integer argument.  When it returns true, push instructions will
be used to pass outgoing arguments.  If the argument is nonzero, it is
the number of bytes to push and indicates the PUSH instruction usage is
optional so that the backend can decide if PUSH instructions should be
generated.  Otherwise, the argument is zero.
2. Implement x86 target hook which returns false when the number of bytes
to push is no less than 16 (8 for 32-bit targets) if vector load and store
can be used.
3. Remove target PUSH_ARGS definitions which return 0 as it is the same
as the default.
4. Define TARGET_PUSH_ARGUMENT of cr16 and m32c to always return true.

gcc/

	PR target/100704
	* calls.c (expand_call): Replace PUSH_ARGS with
	targetm.calls.push_argument (0).
	(emit_library_call_value_1): Likewise.
	* defaults.h (PUSH_ARGS): Removed.
	(PUSH_ARGS_REVERSED): Replace PUSH_ARGS with
	targetm.calls.push_argument (0).
	* expr.c (block_move_libcall_safe_for_call_parm): Likewise.
	(emit_push_insn): Pass the number bytes to push to
	targetm.calls.push_argument and pass 0 if ARGS_ADDR is 0.
	* hooks.c (hook_bool_uint_true): New.
	* hooks.h (hook_bool_uint_true): Likewise.
	* rtlanal.c (nonzero_bits1): Replace PUSH_ARGS with
	targetm.calls.push_argument (0).
	* target.def (push_argument): Add a targetm.calls hook.
	* targhooks.c (default_push_argument): New.
	* targhooks.h (default_push_argument): Likewise.
	* config/bpf/bpf.h (PUSH_ARGS): Removed.
	* config/cr16/cr16.c (TARGET_PUSH_ARGUMENT): New.
	* config/cr16/cr16.h (PUSH_ARGS): Removed.
	* config/i386/i386.c (ix86_push_argument): New.
	(TARGET_PUSH_ARGUMENT): Likewise.
	* config/i386/i386.h (PUSH_ARGS): Removed.
	* config/m32c/m32c.c (TARGET_PUSH_ARGUMENT): New.
	* config/m32c/m32c.h (PUSH_ARGS): Removed.
	* config/nios2/nios2.h (PUSH_ARGS): Likewise.
	* config/pru/pru.h (PUSH_ARGS): Likewise.
	* doc/tm.texi.in: Remove PUSH_ARGS documentation.  Add
	TARGET_PUSH_ARGUMENT hook.
	* doc/tm.texi: Regenerated.

gcc/testsuite/

	PR target/100704
	* gcc.target/i386/pr100704-1.c: New test.
	* gcc.target/i386/pr100704-2.c: Likewise.
	* gcc.target/i386/pr100704-3.c: Likewise.

9 files changed, 20 insertions, 14 deletions

diff --git a/gcc/config/bpf/bpf.h b/gcc/config/bpf/bpf.h
index 4c5b19e..80195ce 100644
--- a/gcc/config/bpf/bpf.h
+++ b/gcc/config/bpf/bpf.h
@@ -288,9 +288,6 @@ enum reg_class
    never used when passing arguments.  However, we still have to
    define the constants below.  */
 
-/* If nonzero, push insns will be used to pass outgoing arguments.  */
-#define PUSH_ARGS 0
-
 /* If nonzero, function arguments will be evaluated from last to
    first, rather than from first to last.  */
 #define PUSH_ARGS_REVERSED 1
diff --git a/gcc/config/cr16/cr16.c b/gcc/config/cr16/cr16.c
index 6c81c39..aaa2260 100644
--- a/gcc/config/cr16/cr16.c
+++ b/gcc/config/cr16/cr16.c
@@ -158,6 +158,8 @@ static void cr16_print_operand_address (FILE *, machine_mode, rtx);
 #define TARGET_CLASS_LIKELY_SPILLED_P	cr16_class_likely_spilled_p
 
 /* Passing function arguments.  */
+#undef TARGET_PUSH_ARGUMENT
+#define TARGET_PUSH_ARGUMENT		hook_bool_uint_true
 #undef TARGET_FUNCTION_ARG
 #define TARGET_FUNCTION_ARG 		cr16_function_arg
 #undef TARGET_FUNCTION_ARG_ADVANCE
diff --git a/gcc/config/cr16/cr16.h b/gcc/config/cr16/cr16.h
index 4ce9e81..a3ad035 100644
--- a/gcc/config/cr16/cr16.h
+++ b/gcc/config/cr16/cr16.h
@@ -376,8 +376,6 @@ enum reg_class
 
 #define ACCUMULATE_OUTGOING_ARGS 0
 
-#define PUSH_ARGS 1
-
 #define PUSH_ROUNDING(BYTES) cr16_push_rounding (BYTES)
 
 #ifndef CUMULATIVE_ARGS
diff --git a/gcc/config/i386/i386.c b/gcc/config/i386/i386.c
index a612558..7d0d414 100644
--- a/gcc/config/i386/i386.c
+++ b/gcc/config/i386/i386.c
@@ -4191,6 +4191,18 @@ ix86_return_in_memory (const_tree type, const_tree fntype ATTRIBUTE_UNUSED)
     }
 }
 
+/* Implement TARGET_PUSH_ARGUMENT.  */
+
+static bool
+ix86_push_argument (unsigned int npush)
+{
+  /* If SSE2 is available, use vector move to put large argument onto
+     stack.  NB:  In 32-bit mode, use 8-byte vector move.  */
+  return ((!TARGET_SSE2 || npush < (TARGET_64BIT ? 16 : 8))
+	  && TARGET_PUSH_ARGS
+	  && !ACCUMULATE_OUTGOING_ARGS);
+}
+
 
 /* Create the va_list data type.  */
 
@@ -23695,6 +23707,8 @@ ix86_run_selftests (void)
 #define TARGET_C_EXCESS_PRECISION ix86_get_excess_precision
 #undef TARGET_PROMOTE_PROTOTYPES
 #define TARGET_PROMOTE_PROTOTYPES hook_bool_const_tree_true
+#undef TARGET_PUSH_ARGUMENT
+#define TARGET_PUSH_ARGUMENT ix86_push_argument
 #undef TARGET_SETUP_INCOMING_VARARGS
 #define TARGET_SETUP_INCOMING_VARARGS ix86_setup_incoming_varargs
 #undef TARGET_MUST_PASS_IN_STACK
diff --git a/gcc/config/i386/i386.h b/gcc/config/i386/i386.h
index 182b327..6e0340a 100644
--- a/gcc/config/i386/i386.h
+++ b/gcc/config/i386/i386.h
@@ -1462,13 +1462,8 @@ enum reg_class
    || TARGET_64BIT_MS_ABI \
    || (TARGET_MACHO && crtl->profile))
 
-/* If defined, a C expression whose value is nonzero when we want to use PUSH
-   instructions to pass outgoing arguments.  */
-
-#define PUSH_ARGS (TARGET_PUSH_ARGS && !ACCUMULATE_OUTGOING_ARGS)
-
 /* We want the stack and args grow in opposite directions, even if
-   PUSH_ARGS is 0.  */
+   targetm.calls.push_argument returns false.  */
 #define PUSH_ARGS_REVERSED 1
 
 /* Offset of first parameter from the argument pointer register value.  */
diff --git a/gcc/config/m32c/m32c.c b/gcc/config/m32c/m32c.c
index b1cb359..d22bdd7 100644
--- a/gcc/config/m32c/m32c.c
+++ b/gcc/config/m32c/m32c.c
@@ -1296,6 +1296,9 @@ m32c_push_rounding (poly_int64 n)
   return (n + 1) & ~1;
 }
 
+#undef TARGET_PUSH_ARGUMENT
+#define TARGET_PUSH_ARGUMENT hook_bool_uint_true
+
 /* Passing Arguments in Registers */
 
 /* Implements TARGET_FUNCTION_ARG.  Arguments are passed partly in
diff --git a/gcc/config/m32c/m32c.h b/gcc/config/m32c/m32c.h
index 635f592..228a73d 100644
--- a/gcc/config/m32c/m32c.h
+++ b/gcc/config/m32c/m32c.h
@@ -472,7 +472,6 @@ enum reg_class
 
 /* Passing Function Arguments on the Stack */
 
-#define PUSH_ARGS 1
 #define PUSH_ROUNDING(N) m32c_push_rounding (N)
 #define CALL_POPS_ARGS(C) 0
 
diff --git a/gcc/config/nios2/nios2.h b/gcc/config/nios2/nios2.h
index 1840a46..dfca12c 100644
--- a/gcc/config/nios2/nios2.h
+++ b/gcc/config/nios2/nios2.h
@@ -297,7 +297,6 @@ typedef struct nios2_args
   ((REGNO) >= FIRST_ARG_REGNO && (REGNO) <= LAST_ARG_REGNO)
 
 /* Passing function arguments on stack.  */
-#define PUSH_ARGS 0
 #define ACCUMULATE_OUTGOING_ARGS 1
 
 /* We define TARGET_RETURN_IN_MEMORY, so set to zero.  */
diff --git a/gcc/config/pru/pru.h b/gcc/config/pru/pru.h
index 4c35a7d..9b6be32 100644
--- a/gcc/config/pru/pru.h
+++ b/gcc/config/pru/pru.h
@@ -339,7 +339,6 @@ typedef struct pru_args
   ((REGNO) >= FIRST_ARG_REGNUM && (REGNO) <= LAST_ARG_REGNUM)
 
 /* Passing function arguments on stack.  */
-#define PUSH_ARGS 0
 #define ACCUMULATE_OUTGOING_ARGS 1
 
 /* We define TARGET_RETURN_IN_MEMORY, so set to zero.  */