i386.opt (recip_mask, [...]): New variables and cl_target member.

	* i386/i386.opt (recip_mask, recip_mask_explicit,
	x_recip_mask_explicit): New variables and cl_target member.
	(mrecip=): New option.
	* i386/i386.h (RECIP_MASK_DIV, RECIP_MASK_SQRT, RECIP_MASK_VEC_DIV,
	RECIP_MASK_VEC_SQRT, RECIP_MASK_ALL, RECIP_MASK_NONE): New bitmasks.
	(TARGET_RECIP_DIV, TARGET_RECIP_SQRT, TARGET_RECIP_VEC_DIV,
	TARGET_RECIP_VEC_SQRT): New tests.
	* i386/i386.md (divsf3): Check TARGET_RECIP_DIV.
	(sqrt<mode>2): Check TARGET_RECIP_SQRT.
	* i386/sse.md (div<mode>3): Check TARGET_RECIP_VEC_DIV.
	(sqrt<mode>2): Check TARGET_RECIP_VEC_SQRT.
	* i386/i386.c (ix86_option_override_internal): Set recip_mask
	for -mrecip and -mrecip=options.
	(ix86_function_specific_save): Save recip_mask_explicit.
	(ix86_function_specific_restore): Restore recip_mask_explicit.

	* doc/invoke.texi (ix86 Options): Document the new option.

From-SVN: r179608

7 files changed, 145 insertions, 5 deletions

diff --git a/gcc/ChangeLog b/gcc/ChangeLog
index 2747f2b..7e6bf33 100644
--- a/gcc/ChangeLog
+++ b/gcc/ChangeLog
@@ -1,3 +1,23 @@
+2011-10-06  Michael Matz  <matz@suse.de>
+
+	* i386/i386.opt (recip_mask, recip_mask_explicit,
+	x_recip_mask_explicit): New variables and cl_target member.
+	(mrecip=): New option.
+	* i386/i386.h (RECIP_MASK_DIV, RECIP_MASK_SQRT, RECIP_MASK_VEC_DIV,
+	RECIP_MASK_VEC_SQRT, RECIP_MASK_ALL, RECIP_MASK_NONE): New bitmasks.
+	(TARGET_RECIP_DIV, TARGET_RECIP_SQRT, TARGET_RECIP_VEC_DIV,
+	TARGET_RECIP_VEC_SQRT): New tests.
+	* i386/i386.md (divsf3): Check TARGET_RECIP_DIV.
+	(sqrt<mode>2): Check TARGET_RECIP_SQRT.
+	* i386/sse.md (div<mode>3): Check TARGET_RECIP_VEC_DIV.
+	(sqrt<mode>2): Check TARGET_RECIP_VEC_SQRT.
+	* i386/i386.c (ix86_option_override_internal): Set recip_mask
+	for -mrecip and -mrecip=options.
+	(ix86_function_specific_save): Save recip_mask_explicit.
+	(ix86_function_specific_restore): Restore recip_mask_explicit.
+
+	* doc/invoke.texi (ix86 Options): Document the new option.
+
 2011-10-06  Bernd Schmidt  <bernds@codesourcery.com>
 
 	PR target/49049
diff --git a/gcc/config/i386/i386.c b/gcc/config/i386/i386.c
index faad3a5..688fba1 100644
--- a/gcc/config/i386/i386.c
+++ b/gcc/config/i386/i386.c
@@ -3057,6 +3057,22 @@ ix86_option_override_internal (bool main_args_p)
 	PTA_64BIT /* flags are only used for -march switch.  */ },
     };
 
+  /* -mrecip options.  */
+  static struct
+    {
+      const char *string;           /* option name */
+      unsigned int mask;            /* mask bits to set */
+    }
+  const recip_options[] =
+    {
+      { "all",       RECIP_MASK_ALL },
+      { "none",      RECIP_MASK_NONE },
+      { "div",       RECIP_MASK_DIV },
+      { "sqrt",      RECIP_MASK_SQRT },
+      { "vec-div",   RECIP_MASK_VEC_DIV },
+      { "vec-sqrt",  RECIP_MASK_VEC_SQRT },
+    };
+
   int const pta_size = ARRAY_SIZE (processor_alias_table);
 
   /* Set up prefix/suffix so the error messages refer to either the command
@@ -3814,6 +3830,56 @@ ix86_option_override_internal (bool main_args_p)
       target_flags &= ~MASK_VZEROUPPER;
     }
 
+  if (ix86_recip_name)
+    {
+      char *p = ASTRDUP (ix86_recip_name);
+      char *q;
+      unsigned int mask, i;
+      bool invert;
+
+      while ((q = strtok (p, ",")) != NULL)
+	{
+	  p = NULL;
+	  if (*q == '!')
+	    {
+	      invert = true;
+	      q++;
+	    }
+	  else
+	    invert = false;
+
+	  if (!strcmp (q, "default"))
+	    mask = RECIP_MASK_ALL;
+	  else
+	    {
+	      for (i = 0; i < ARRAY_SIZE (recip_options); i++)
+		if (!strcmp (q, recip_options[i].string))
+		  {
+		    mask = recip_options[i].mask;
+		    break;
+		  }
+
+	      if (i == ARRAY_SIZE (recip_options))
+		{
+		  error ("unknown option for -mrecip=%s", q);
+		  invert = false;
+		  mask = RECIP_MASK_NONE;
+		}
+	    }
+
+	  recip_mask_explicit |= mask;
+	  if (invert)
+	    recip_mask &= ~mask;
+	  else
+	    recip_mask |= mask;
+	}
+    }
+
+  if (TARGET_RECIP)
+    recip_mask |= RECIP_MASK_ALL & ~recip_mask_explicit;
+  else if (target_flags_explicit & MASK_RECIP)
+    recip_mask &= ~(RECIP_MASK_ALL & ~recip_mask_explicit);
+
   /* Save the initial options in case the user does function specific
      options.  */
   if (main_args_p)
@@ -3946,6 +4012,7 @@ ix86_function_specific_save (struct cl_target_option *ptr)
   ptr->arch_specified = ix86_arch_specified;
   ptr->x_ix86_isa_flags_explicit = ix86_isa_flags_explicit;
   ptr->ix86_target_flags_explicit = target_flags_explicit;
+  ptr->x_recip_mask_explicit = recip_mask_explicit;
 
   /* The fields are char but the variables are not; make sure the
      values fit in the fields.  */
@@ -3973,6 +4040,7 @@ ix86_function_specific_restore (struct cl_target_option *ptr)
   ix86_arch_specified = ptr->arch_specified;
   ix86_isa_flags_explicit = ptr->x_ix86_isa_flags_explicit;
   target_flags_explicit = ptr->ix86_target_flags_explicit;
+  recip_mask_explicit = ptr->x_recip_mask_explicit;
 
   /* Recreate the arch feature tests if the arch changed */
   if (old_arch != ix86_arch)
diff --git a/gcc/config/i386/i386.h b/gcc/config/i386/i386.h
index 7d6e058..bd69ec2 100644
--- a/gcc/config/i386/i386.h
+++ b/gcc/config/i386/i386.h
@@ -2315,6 +2315,19 @@ extern void debug_dispatch_window (int);
 	((FLAGS) & (IX86_CALLCVT_CDECL | IX86_CALLCVT_STDCALL \
 		    | IX86_CALLCVT_FASTCALL | IX86_CALLCVT_THISCALL))
 
+#define RECIP_MASK_NONE		0x00
+#define RECIP_MASK_DIV		0x01
+#define RECIP_MASK_SQRT		0x02
+#define RECIP_MASK_VEC_DIV	0x04
+#define RECIP_MASK_VEC_SQRT	0x08
+#define RECIP_MASK_ALL	(RECIP_MASK_DIV | RECIP_MASK_SQRT \
+			 | RECIP_MASK_VEC_DIV | RECIP_MASK_VEC_SQRT)
+
+#define TARGET_RECIP_DIV	((recip_mask & RECIP_MASK_DIV) != 0)
+#define TARGET_RECIP_SQRT	((recip_mask & RECIP_MASK_SQRT) != 0)
+#define TARGET_RECIP_VEC_DIV	((recip_mask & RECIP_MASK_VEC_DIV) != 0)
+#define TARGET_RECIP_VEC_SQRT	((recip_mask & RECIP_MASK_VEC_SQRT) != 0)
+
 /*
 Local variables:
 version-control: t
diff --git a/gcc/config/i386/i386.md b/gcc/config/i386/i386.md
index b8a649c..a11a71b 100644
--- a/gcc/config/i386/i386.md
+++ b/gcc/config/i386/i386.md
@@ -7062,7 +7062,9 @@
   "(TARGET_80387 && X87_ENABLE_ARITH (SFmode))
     || TARGET_SSE_MATH"
 {
-  if (TARGET_SSE_MATH && TARGET_RECIP && optimize_insn_for_speed_p ()
+  if (TARGET_SSE_MATH
+      && TARGET_RECIP_DIV
+      && optimize_insn_for_speed_p ()
       && flag_finite_math_only && !flag_trapping_math
       && flag_unsafe_math_optimizations)
     {
@@ -13438,7 +13440,9 @@
    || (SSE_FLOAT_MODE_P (<MODE>mode) && TARGET_SSE_MATH)"
 {
   if (<MODE>mode == SFmode
-      && TARGET_SSE_MATH && TARGET_RECIP && !optimize_function_for_size_p (cfun)
+      && TARGET_SSE_MATH
+      && TARGET_RECIP_SQRT
+      && !optimize_function_for_size_p (cfun)
       && flag_finite_math_only && !flag_trapping_math
       && flag_unsafe_math_optimizations)
     {
diff --git a/gcc/config/i386/i386.opt b/gcc/config/i386/i386.opt
index 8e4d51b..43009a3 100644
--- a/gcc/config/i386/i386.opt
+++ b/gcc/config/i386/i386.opt
@@ -31,6 +31,15 @@ HOST_WIDE_INT ix86_isa_flags = TARGET_64BIT_DEFAULT | TARGET_SUBTARGET_ISA_DEFAU
 Variable
 HOST_WIDE_INT ix86_isa_flags_explicit
 
+TargetVariable
+int recip_mask
+
+Variable
+int recip_mask_explicit
+
+TargetSave
+int x_recip_mask_explicit
+
 ;; Definitions to add to the cl_target_option structure
 ;; -march= processor
 TargetSave
@@ -373,6 +382,10 @@ mrecip
 Target Report Mask(RECIP) Save
 Generate reciprocals instead of divss and sqrtss.
 
+mrecip=
+Target Report RejectNegative Joined Var(ix86_recip_name)
+Control generation of reciprocal estimates.
+
 mcld
 Target Report Mask(CLD) Save
 Generate cld instruction in the function prologue.
diff --git a/gcc/config/i386/sse.md b/gcc/config/i386/sse.md
index ee9cf0b..88f4d6c 100644
--- a/gcc/config/i386/sse.md
+++ b/gcc/config/i386/sse.md
@@ -779,7 +779,9 @@
 {
   ix86_fixup_binary_operands_no_copy (DIV, <MODE>mode, operands);
 
-  if (TARGET_SSE_MATH && TARGET_RECIP && !optimize_insn_for_size_p ()
+  if (TARGET_SSE_MATH
+      && TARGET_RECIP_VEC_DIV
+      && !optimize_insn_for_size_p ()
       && flag_finite_math_only && !flag_trapping_math
       && flag_unsafe_math_optimizations)
     {
@@ -857,7 +859,9 @@
 	(sqrt:VF1 (match_operand:VF1 1 "nonimmediate_operand" "")))]
   "TARGET_SSE"
 {
-  if (TARGET_SSE_MATH && TARGET_RECIP && !optimize_insn_for_size_p ()
+  if (TARGET_SSE_MATH
+      && TARGET_RECIP_VEC_SQRT
+      && !optimize_insn_for_size_p ()
       && flag_finite_math_only && !flag_trapping_math
       && flag_unsafe_math_optimizations)
     {
diff --git a/gcc/doc/invoke.texi b/gcc/doc/invoke.texi
index 0588284..ef7ac68 100644
--- a/gcc/doc/invoke.texi
+++ b/gcc/doc/invoke.texi
@@ -605,7 +605,9 @@ Objective-C and Objective-C++ Dialects}.
 -mno-wide-multiply  -mrtd  -malign-double @gol
 -mpreferred-stack-boundary=@var{num} @gol
 -mincoming-stack-boundary=@var{num} @gol
--mcld -mcx16 -msahf -mmovbe -mcrc32 -mrecip -mvzeroupper @gol
+-mcld -mcx16 -msahf -mmovbe -mcrc32 @gol
+-mrecip -mrecip=@var{opt} @gol
+-mvzeroupper @gol
 -mmmx  -msse  -msse2 -msse3 -mssse3 -msse4.1 -msse4.2 -msse4 -mavx @gol
 -mavx2 -maes -mpclmul -mfsgsbase -mrdrnd -mf16c -mfma @gol
 -msse4a -m3dnow -mpopcnt -mabm -mbmi -mtbm -mfma4 -mxop -mlzcnt @gol
@@ -12871,6 +12873,22 @@ Note that GCC implements 1.0f/sqrtf(x) in terms of RSQRTSS (or RSQRTPS)
 already with @option{-ffast-math} (or the above option combination), and
 doesn't need @option{-mrecip}.
 
+@item -mrecip=@var{opt}
+@opindex mrecip=opt
+This option allows to control which reciprocal estimate instructions
+may be used.  @var{opt} is a comma separated list of options, that may
+be preceded by a @code{!} to invert the option:
+@code{all}: enable all estimate instructions,
+@code{default}: enable the default instructions, equivalent to @option{-mrecip},
+@code{none}: disable all estimate instructions, equivalent to @option{-mno-recip},
+@code{div}: enable the approximation for scalar division,
+@code{vec-div}: enable the approximation for vectorized division,
+@code{sqrt}: enable the approximation for scalar square root,
+@code{vec-sqrt}: enable the approximation for vectorized square root.
+
+So for example, @option{-mrecip=all,!sqrt} would enable
+all of the reciprocal approximations, except for square root.
+
 @item -mveclibabi=@var{type}
 @opindex mveclibabi
 Specifies the ABI type to use for vectorizing intrinsics using an