diff mbox

[v2,SPARC] Add -mfsmuld option

Message ID 20170726085300.14685-1-sebastian.huber@embedded-brains.de
State New
Headers show

Commit Message

Sebastian Huber July 26, 2017, 8:53 a.m. UTC 
Add the -mfsmuld option to control the generation of the FsMULd
instruction.  In general, this instruction is available in architecture
version V8 and V9 CPUs with FPU.  Some CPUs of this category do not
support this instruction properly, e.g. AT697E, AT697F and UT699.  Some
CPUs of this category do not implement it in hardware, e.g. LEON3/4 with
GRFPU-lite.

gcc/
	* config/sparc/sparc.c (dump_target_flag_bits): Dump MASK_FSMULD.
	(sparc_option_override): Honour MASK_FSMULD.
	* config/sparc/sparc.h (MASK_FEATURES): Add MASK_FSMULD.
	* config/sparc/sparc.md (muldf3_extend): Use TARGET_FSMULD.
	* config/sparc/sparc.opt (mfsmuld): New option.
	* doc/invoke.texi (mfsmuld): Document option.
---
 gcc/config/sparc/sparc.c   | 30 ++++++++++++++++++++----------
 gcc/config/sparc/sparc.h   |  3 ++-
 gcc/config/sparc/sparc.md  |  2 +-
 gcc/config/sparc/sparc.opt |  4 ++++
 gcc/doc/invoke.texi        | 11 ++++++++++-
 5 files changed, 37 insertions(+), 13 deletions(-)

Comments

Eric Botcazou July 26, 2017, 12:13 p.m. UTC | #1 
> Add the -mfsmuld option to control the generation of the FsMULd
> instruction.  In general, this instruction is available in architecture
> version V8 and V9 CPUs with FPU.  Some CPUs of this category do not
> support this instruction properly, e.g. AT697E, AT697F and UT699.  Some
> CPUs of this category do not implement it in hardware, e.g. LEON3/4 with
> GRFPU-lite.
> 
> gcc/
> 	* config/sparc/sparc.c (dump_target_flag_bits): Dump MASK_FSMULD.
> 	(sparc_option_override): Honour MASK_FSMULD.
> 	* config/sparc/sparc.h (MASK_FEATURES): Add MASK_FSMULD.
> 	* config/sparc/sparc.md (muldf3_extend): Use TARGET_FSMULD.
> 	* config/sparc/sparc.opt (mfsmuld): New option.
> 	* doc/invoke.texi (mfsmuld): Document option.

OK for mainline and 7 branch modulo:

> @@ -1511,6 +1513,11 @@ sparc_option_override (void)
>        target_flags |= MASK_LONG_DOUBLE_128;
>      }
> 
> +  /* Enable the FSMULD instruction by default if not explicitly configured
> by +     the user.  It may be later disabled by the CPU target flags or if
> +     !TARGET_FPU.  */
> +  target_flags |= MASK_FSMULD & ~target_flags_explicit;

I think that:

  if (!(target_flags_explicit & MASK_FSMULD))
    target_flags |= MASK_FSMULD;

is easier to grasp (and there is a precedent with MASK_LRA a few lines below).

>    /* Code model selection.  */
>    sparc_cmodel = SPARC_DEFAULT_CMODEL;
> 
> @@ -1603,11 +1610,11 @@ sparc_option_override (void)
>    if (TARGET_VIS4B)
>      target_flags |= MASK_VIS4 | MASK_VIS3 | MASK_VIS2 | MASK_VIS;
> 
> -  /* Don't allow -mvis, -mvis2, -mvis3, -mvis4, -mvis4b and -mfmaf if
> +  /* Don't allow -mvis, -mvis2, -mvis3, -mvis4, -mvis4b, -mfmaf and
> -mfsmuld if FPU is disabled.  */
>    if (! TARGET_FPU)
>      target_flags &= ~(MASK_VIS | MASK_VIS2 | MASK_VIS3 | MASK_VIS4
> -		      | MASK_VIS4B | MASK_FMAF);
> +		      | MASK_VIS4B | MASK_FMAF | MASK_FSMULD);
> 
>    /* -mvis assumes UltraSPARC+, so we are sure v9 instructions
>       are available; -m64 also implies v9.  */
> @@ -1641,6 +1648,9 @@ sparc_option_override (void)
>    if (sparc_fix_ut699 || sparc_fix_ut700 || sparc_fix_gr712rc)
>      sparc_fix_b2bst = 1;
> 
> +  if (sparc_fix_ut699)
> +    target_flags &= ~MASK_FSMULD;

Add a stupid comment line here, something like:

"Disable FsMULd for the UT699 since it doesn't work correctly."
Sebastian Huber July 26, 2017, 12:44 p.m. UTC | #2 
On 26/07/17 14:13, Eric Botcazou wrote:

>> Add the -mfsmuld option to control the generation of the FsMULd
>> instruction.  In general, this instruction is available in architecture
>> version V8 and V9 CPUs with FPU.  Some CPUs of this category do not
>> support this instruction properly, e.g. AT697E, AT697F and UT699.  Some
>> CPUs of this category do not implement it in hardware, e.g. LEON3/4 with
>> GRFPU-lite.
>>
>> gcc/
>> 	* config/sparc/sparc.c (dump_target_flag_bits): Dump MASK_FSMULD.
>> 	(sparc_option_override): Honour MASK_FSMULD.
>> 	* config/sparc/sparc.h (MASK_FEATURES): Add MASK_FSMULD.
>> 	* config/sparc/sparc.md (muldf3_extend): Use TARGET_FSMULD.
>> 	* config/sparc/sparc.opt (mfsmuld): New option.
>> 	* doc/invoke.texi (mfsmuld): Document option.
> OK for mainline and 7 branch modulo:
>

Thanks for your quick review. I am really glad that we can now use the 
upcoming GCC 7.2 release.

I checked it in as r250570 and r250571.
Sebastian Huber July 26, 2017, 1:07 p.m. UTC | #3 
On 26/07/17 14:44, Sebastian Huber wrote:

> On 26/07/17 14:13, Eric Botcazou wrote:
>
>>> Add the -mfsmuld option to control the generation of the FsMULd
>>> instruction.  In general, this instruction is available in architecture
>>> version V8 and V9 CPUs with FPU.  Some CPUs of this category do not
>>> support this instruction properly, e.g. AT697E, AT697F and UT699.  Some
>>> CPUs of this category do not implement it in hardware, e.g. LEON3/4 
>>> with
>>> GRFPU-lite.
>>>
>>> gcc/
>>>     * config/sparc/sparc.c (dump_target_flag_bits): Dump MASK_FSMULD.
>>>     (sparc_option_override): Honour MASK_FSMULD.
>>>     * config/sparc/sparc.h (MASK_FEATURES): Add MASK_FSMULD.
>>>     * config/sparc/sparc.md (muldf3_extend): Use TARGET_FSMULD.
>>>     * config/sparc/sparc.opt (mfsmuld): New option.
>>>     * doc/invoke.texi (mfsmuld): Document option.
>> OK for mainline and 7 branch modulo:
>>
>
> Thanks for your quick review. I am really glad that we can now use the 
> upcoming GCC 7.2 release.
>
> I checked it in as r250570 and r250571.
>

I would like to add this to the web site:

Index: htdocs/gcc-7/changes.html
===================================================================
RCS file: /cvs/gcc/wwwdocs/htdocs/gcc-7/changes.html,v
retrieving revision 1.88
diff -r1.88 changes.html
1248a1249,1251
 >     <li>Use of the Floating-point Multiply Single to Double (FsMULd)
 >         instruction can now be controlled by the 
<code>-mfsmuld</code> and
 >         <code>-fno-fsmuld</code> options.</li>
cvs diff: Diffing htdocs/gcc-8
Index: htdocs/gcc-8/changes.html
===================================================================
RCS file: /cvs/gcc/wwwdocs/htdocs/gcc-8/changes.html,v
retrieving revision 1.7
diff -r1.7 changes.html
148,149c148,153
< <!-- <h3 id="sparc">SPARC</h3> -->
<
---
 > <h3 id="sparc">SPARC</h3>
 > <ul>
 >   <li>Use of the Floating-point Multiply Single to Double (FsMULd) 
instruction
 >       can now be controlled by the <code>-mfsmuld</code> and
 >       <code>-fno-fsmuld</code> options.</li>
 > </ul>
Eric Botcazou July 26, 2017, 2:02 p.m. UTC | #4 
> I would like to add this to the web site:
> 
> Index: htdocs/gcc-7/changes.html
> ===================================================================
> RCS file: /cvs/gcc/wwwdocs/htdocs/gcc-7/changes.html,v
> retrieving revision 1.88
> diff -r1.88 changes.html
> 1248a1249,1251
> 
>  >     <li>Use of the Floating-point Multiply Single to Double (FsMULd)
>  >     
>  >         instruction can now be controlled by the
> 
> <code>-mfsmuld</code> and
> 
>  >         <code>-fno-fsmuld</code> options.</li>
> 

We document changes for only one release so the above is sufficient and OK.
diff mbox

Patch

diff --git a/gcc/config/sparc/sparc.c b/gcc/config/sparc/sparc.c
index 674a3823cb9..8eed2fc5621 100644
--- a/gcc/config/sparc/sparc.c
+++ b/gcc/config/sparc/sparc.c
@@ -1304,6 +1304,8 @@  dump_target_flag_bits (const int flags)
     fprintf (stderr, "FLAT ");
   if (flags & MASK_FMAF)
     fprintf (stderr, "FMAF ");
+  if (flags & MASK_FSMULD)
+    fprintf (stderr, "FSMULD ");
   if (flags & MASK_FPU)
     fprintf (stderr, "FPU ");
   if (flags & MASK_HARD_QUAD)
@@ -1403,24 +1405,24 @@  sparc_option_override (void)
     const int disable;
     const int enable;
   } const cpu_table[] = {
-    { "v7",		MASK_ISA, 0 },
-    { "cypress",	MASK_ISA, 0 },
+    { "v7",		MASK_ISA|MASK_FSMULD, 0 },
+    { "cypress",	MASK_ISA|MASK_FSMULD, 0 },
     { "v8",		MASK_ISA, MASK_V8 },
     /* TI TMS390Z55 supersparc */
     { "supersparc",	MASK_ISA, MASK_V8 },
     { "hypersparc",	MASK_ISA, MASK_V8 },
-    { "leon",		MASK_ISA, MASK_V8|MASK_LEON },
+    { "leon",		MASK_ISA|MASK_FSMULD, MASK_V8|MASK_LEON },
     { "leon3",		MASK_ISA, MASK_V8|MASK_LEON3 },
-    { "leon3v7",	MASK_ISA, MASK_LEON3 },
-    { "sparclite",	MASK_ISA, MASK_SPARCLITE },
+    { "leon3v7",	MASK_ISA|MASK_FSMULD, MASK_LEON3 },
+    { "sparclite",	MASK_ISA|MASK_FSMULD, MASK_SPARCLITE },
     /* The Fujitsu MB86930 is the original sparclite chip, with no FPU.  */
     { "f930",		MASK_ISA|MASK_FPU, MASK_SPARCLITE },
     /* The Fujitsu MB86934 is the recent sparclite chip, with an FPU.  */
-    { "f934",		MASK_ISA, MASK_SPARCLITE },
+    { "f934",		MASK_ISA|MASK_FSMULD, MASK_SPARCLITE },
     { "sparclite86x",	MASK_ISA|MASK_FPU, MASK_SPARCLITE },
-    { "sparclet",	MASK_ISA, MASK_SPARCLET },
+    { "sparclet",	MASK_ISA|MASK_FSMULD, MASK_SPARCLET },
     /* TEMIC sparclet */
-    { "tsc701",		MASK_ISA, MASK_SPARCLET },
+    { "tsc701",		MASK_ISA|MASK_FSMULD, MASK_SPARCLET },
     { "v9",		MASK_ISA, MASK_V9 },
     /* UltraSPARC I, II, IIi */
     { "ultrasparc",	MASK_ISA,
@@ -1511,6 +1513,11 @@  sparc_option_override (void)
       target_flags |= MASK_LONG_DOUBLE_128;
     }
 
+  /* Enable the FSMULD instruction by default if not explicitly configured by
+     the user.  It may be later disabled by the CPU target flags or if
+     !TARGET_FPU.  */
+  target_flags |= MASK_FSMULD & ~target_flags_explicit;
+
   /* Code model selection.  */
   sparc_cmodel = SPARC_DEFAULT_CMODEL;
 
@@ -1603,11 +1610,11 @@  sparc_option_override (void)
   if (TARGET_VIS4B)
     target_flags |= MASK_VIS4 | MASK_VIS3 | MASK_VIS2 | MASK_VIS;
 
-  /* Don't allow -mvis, -mvis2, -mvis3, -mvis4, -mvis4b and -mfmaf if
+  /* Don't allow -mvis, -mvis2, -mvis3, -mvis4, -mvis4b, -mfmaf and -mfsmuld if
      FPU is disabled.  */
   if (! TARGET_FPU)
     target_flags &= ~(MASK_VIS | MASK_VIS2 | MASK_VIS3 | MASK_VIS4
-		      | MASK_VIS4B | MASK_FMAF);
+		      | MASK_VIS4B | MASK_FMAF | MASK_FSMULD);
 
   /* -mvis assumes UltraSPARC+, so we are sure v9 instructions
      are available; -m64 also implies v9.  */
@@ -1641,6 +1648,9 @@  sparc_option_override (void)
   if (sparc_fix_ut699 || sparc_fix_ut700 || sparc_fix_gr712rc)
     sparc_fix_b2bst = 1;
 
+  if (sparc_fix_ut699)
+    target_flags &= ~MASK_FSMULD;
+
   /* Supply a default value for align_functions.  */
   if (align_functions == 0)
     {
diff --git a/gcc/config/sparc/sparc.h b/gcc/config/sparc/sparc.h
index d7c617e06c3..15a62179af5 100644
--- a/gcc/config/sparc/sparc.h
+++ b/gcc/config/sparc/sparc.h
@@ -438,7 +438,8 @@  extern enum cmodel sparc_cmodel;
 /* Mask of all CPU feature flags.  */
 #define MASK_FEATURES						\
   (MASK_FPU + MASK_HARD_QUAD + MASK_VIS + MASK_VIS2 + MASK_VIS3	\
-   + MASK_VIS4 + MASK_CBCOND + MASK_FMAF + MASK_POPC + MASK_SUBXC)
+   + MASK_VIS4 + MASK_CBCOND + MASK_FMAF + MASK_FSMULD		\
+   + MASK_POPC + MASK_SUBXC)
  
 /* TARGET_HARD_MUL: Use 32-bit hardware multiply instructions but not %y.  */
 #define TARGET_HARD_MUL				\
diff --git a/gcc/config/sparc/sparc.md b/gcc/config/sparc/sparc.md
index b154003c54a..751bacdbcac 100644
--- a/gcc/config/sparc/sparc.md
+++ b/gcc/config/sparc/sparc.md
@@ -6121,7 +6121,7 @@  visl")
   [(set (match_operand:DF 0 "register_operand" "=e")
 	(mult:DF (float_extend:DF (match_operand:SF 1 "register_operand" "f"))
 		 (float_extend:DF (match_operand:SF 2 "register_operand" "f"))))]
-  "(TARGET_V8 || TARGET_V9) && TARGET_FPU && !sparc_fix_ut699"
+  "TARGET_FSMULD"
   "fsmuld\t%1, %2, %0"
   [(set_attr "type" "fpmul")
    (set_attr "fptype" "double")])
diff --git a/gcc/config/sparc/sparc.opt b/gcc/config/sparc/sparc.opt
index ae63d2018e3..22267f50e90 100644
--- a/gcc/config/sparc/sparc.opt
+++ b/gcc/config/sparc/sparc.opt
@@ -93,6 +93,10 @@  mfmaf
 Target Report Mask(FMAF)
 Use UltraSPARC Fused Multiply-Add extensions.
 
+mfsmuld
+Target Report Mask(FSMULD)
+Use Floating-point Multiply Single to Double (FsMULd) instruction.
+
 mpopc
 Target Report Mask(POPC)
 Use UltraSPARC Population-Count instruction.
diff --git a/gcc/doc/invoke.texi b/gcc/doc/invoke.texi
index a6da37c8203..6e174c5b3ff 100644
--- a/gcc/doc/invoke.texi
+++ b/gcc/doc/invoke.texi
@@ -1124,7 +1124,7 @@  See RS/6000 and PowerPC Options.
 -mv8plus  -mno-v8plus  -mvis  -mno-vis @gol
 -mvis2  -mno-vis2  -mvis3  -mno-vis3 @gol
 -mvis4 -mno-vis4 -mvis4b -mno-vis4b @gol
--mcbcond  -mno-cbcond  -mfmaf  -mno-fmaf  @gol
+-mcbcond  -mno-cbcond  -mfmaf  -mno-fmaf  -mfsmuld  -mno-fsmuld  @gol
 -mpopc  -mno-popc  -msubxc  -mno-subxc @gol
 -mfix-at697f  -mfix-ut699  -mfix-ut700  -mfix-gr712rc @gol
 -mlra  -mno-lra}
@@ -24069,6 +24069,15 @@  Fused Multiply-Add Floating-point instructions.  The default is @option{-mfmaf}
 when targeting a CPU that supports such instructions, such as Niagara-3 and
 later.
 
+@item -mfsmuld
+@itemx -mno-fsmuld
+@opindex mfsmuld
+@opindex mno-fsmuld
+With @option{-mfsmuld}, GCC generates code that takes advantage of the
+Floating-point Multiply Single to Double (FsMULd) instruction.  The default is
+@option{-mfsmuld} when targeting a CPU supporting the architecture versions V8
+or V9 with FPU except @option{-mcpu=leon}.
+
 @item -mpopc
 @itemx -mno-popc
 @opindex mpopc