re PR bootstrap/85681 (r259995 breaks bootstrap on x86_64-*-freebsd)

2018-05-07  Luis Machado  <luis.machado@linaro.org>

	PR bootstrap/85681
	Revert:
	2018-05-07  Luis Machado  <luis.machado@linaro.org>

	* config/aarch64/aarch64-protos.h (cpu_prefetch_tune)
	<prefetch_dynamic_strides>: New const bool field.
	* config/aarch64/aarch64.c (generic_prefetch_tune): Update to include
	prefetch_dynamic_strides.
	(exynosm1_prefetch_tune): Likewise.
	(thunderxt88_prefetch_tune): Likewise.
	(thunderx_prefetch_tune): Likewise.
	(thunderx2t99_prefetch_tune): Likewise.
	(qdf24xx_prefetch_tune): Likewise. Set prefetch_dynamic_strides to false.
	(aarch64_override_options_internal): Update to set
	PARAM_PREFETCH_DYNAMIC_STRIDES.
	* doc/invoke.texi (prefetch-dynamic-strides): Document new option.
	* params.def (PARAM_PREFETCH_DYNAMIC_STRIDES): New.
	* params.h (PARAM_PREFETCH_DYNAMIC_STRIDES): Define.
	* tree-ssa-loop-prefetch.c (should_issue_prefetch_p): Account for
	prefetch-dynamic-strides setting.

	2018-05-07  Luis Machado  <luis.machado@linaro.org>

	* config/aarch64/aarch64-protos.h (cpu_prefetch_tune)
	<minimum_stride>: New const int field.
	* config/aarch64/aarch64.c (generic_prefetch_tune): Update to include
	minimum_stride field.
	(exynosm1_prefetch_tune): Likewise.
	(thunderxt88_prefetch_tune): Likewise.
	(thunderx_prefetch_tune): Likewise.
	(thunderx2t99_prefetch_tune): Likewise.
	(qdf24xx_prefetch_tune): Likewise. Set minimum_stride to 2048.
	(aarch64_override_options_internal): Update to set
	PARAM_PREFETCH_MINIMUM_STRIDE.
	* doc/invoke.texi (prefetch-minimum-stride): Document new option.
	* params.def (PARAM_PREFETCH_MINIMUM_STRIDE): New.
	* params.h (PARAM_PREFETCH_MINIMUM_STRIDE): Define.
	* tree-ssa-loop-prefetch.c (should_issue_prefetch_p): Return false if
	stride is constant and is below the minimum stride threshold.

From-SVN: r260000

7 files changed, 43 insertions, 102 deletions

diff --git a/gcc/ChangeLog b/gcc/ChangeLog
index 6a5a871901c..cb5582b86ad 100644
--- a/gcc/ChangeLog
+++ b/gcc/ChangeLog
@@ -1,5 +1,47 @@
 2018-05-07  Luis Machado  <luis.machado@linaro.org>
 
+	PR bootstrap/85681
+	Revert:
+	2018-05-07  Luis Machado  <luis.machado@linaro.org>
+
+	* config/aarch64/aarch64-protos.h (cpu_prefetch_tune)
+	<prefetch_dynamic_strides>: New const bool field.
+	* config/aarch64/aarch64.c (generic_prefetch_tune): Update to include
+	prefetch_dynamic_strides.
+	(exynosm1_prefetch_tune): Likewise.
+	(thunderxt88_prefetch_tune): Likewise.
+	(thunderx_prefetch_tune): Likewise.
+	(thunderx2t99_prefetch_tune): Likewise.
+	(qdf24xx_prefetch_tune): Likewise. Set prefetch_dynamic_strides to false.
+	(aarch64_override_options_internal): Update to set
+	PARAM_PREFETCH_DYNAMIC_STRIDES.
+	* doc/invoke.texi (prefetch-dynamic-strides): Document new option.
+	* params.def (PARAM_PREFETCH_DYNAMIC_STRIDES): New.
+	* params.h (PARAM_PREFETCH_DYNAMIC_STRIDES): Define.
+	* tree-ssa-loop-prefetch.c (should_issue_prefetch_p): Account for
+	prefetch-dynamic-strides setting.
+
+	2018-05-07  Luis Machado  <luis.machado@linaro.org>
+
+	* config/aarch64/aarch64-protos.h (cpu_prefetch_tune)
+	<minimum_stride>: New const int field.
+	* config/aarch64/aarch64.c (generic_prefetch_tune): Update to include
+	minimum_stride field.
+	(exynosm1_prefetch_tune): Likewise.
+	(thunderxt88_prefetch_tune): Likewise.
+	(thunderx_prefetch_tune): Likewise.
+	(thunderx2t99_prefetch_tune): Likewise.
+	(qdf24xx_prefetch_tune): Likewise. Set minimum_stride to 2048.
+	(aarch64_override_options_internal): Update to set
+	PARAM_PREFETCH_MINIMUM_STRIDE.
+	* doc/invoke.texi (prefetch-minimum-stride): Document new option.
+	* params.def (PARAM_PREFETCH_MINIMUM_STRIDE): New.
+	* params.h (PARAM_PREFETCH_MINIMUM_STRIDE): Define.
+	* tree-ssa-loop-prefetch.c (should_issue_prefetch_p): Return false if
+	stride is constant and is below the minimum stride threshold.
+
+2018-05-07  Luis Machado  <luis.machado@linaro.org>
+
 	* config/aarch64/aarch64.c (qdf24xx_prefetch_tune) <l2_cache_size>: Set
 	to 512.
 
diff --git a/gcc/config/aarch64/aarch64-protos.h b/gcc/config/aarch64/aarch64-protos.h
index 157308ddb79..cda2895d28e 100644
--- a/gcc/config/aarch64/aarch64-protos.h
+++ b/gcc/config/aarch64/aarch64-protos.h
@@ -230,12 +230,6 @@ struct cpu_prefetch_tune
   const int l1_cache_size;
   const int l1_cache_line_size;
   const int l2_cache_size;
-  /* Whether software prefetch hints should be issued for non-constant
-     strides.  */
-  const bool prefetch_dynamic_strides;
-  /* The minimum constant stride beyond which we should use prefetch
-     hints for.  */
-  const int minimum_stride;
   const int default_opt_level;
 };
 
diff --git a/gcc/config/aarch64/aarch64.c b/gcc/config/aarch64/aarch64.c
index b50e6c45b2a..6847b9a683c 100644
--- a/gcc/config/aarch64/aarch64.c
+++ b/gcc/config/aarch64/aarch64.c
@@ -547,8 +547,6 @@ static const cpu_prefetch_tune generic_prefetch_tune =
   -1,			/* l1_cache_size  */
   -1,			/* l1_cache_line_size  */
   -1,			/* l2_cache_size  */
-  true,			/* prefetch_dynamic_strides */
-  -1,			/* minimum_stride */
   -1			/* default_opt_level  */
 };
 
@@ -558,8 +556,6 @@ static const cpu_prefetch_tune exynosm1_prefetch_tune =
   -1,			/* l1_cache_size  */
   64,			/* l1_cache_line_size  */
   -1,			/* l2_cache_size  */
-  true,			/* prefetch_dynamic_strides */
-  -1,			/* minimum_stride */
   -1			/* default_opt_level  */
 };
 
@@ -569,9 +565,7 @@ static const cpu_prefetch_tune qdf24xx_prefetch_tune =
   32,			/* l1_cache_size  */
   64,			/* l1_cache_line_size  */
   512,			/* l2_cache_size  */
-  false,		/* prefetch_dynamic_strides */
-  2048,			/* minimum_stride */
-  3			/* default_opt_level  */
+  -1			/* default_opt_level  */
 };
 
 static const cpu_prefetch_tune thunderxt88_prefetch_tune =
@@ -580,8 +574,6 @@ static const cpu_prefetch_tune thunderxt88_prefetch_tune =
   32,			/* l1_cache_size  */
   128,			/* l1_cache_line_size  */
   16*1024,		/* l2_cache_size  */
-  true,			/* prefetch_dynamic_strides */
-  -1,			/* minimum_stride */
   3			/* default_opt_level  */
 };
 
@@ -591,8 +583,6 @@ static const cpu_prefetch_tune thunderx_prefetch_tune =
   32,			/* l1_cache_size  */
   128,			/* l1_cache_line_size  */
   -1,			/* l2_cache_size  */
-  true,			/* prefetch_dynamic_strides */
-  -1,			/* minimum_stride */
   -1			/* default_opt_level  */
 };
 
@@ -602,8 +592,6 @@ static const cpu_prefetch_tune thunderx2t99_prefetch_tune =
   32,			/* l1_cache_size  */
   64,			/* l1_cache_line_size  */
   256,			/* l2_cache_size  */
-  true,			/* prefetch_dynamic_strides */
-  -1,			/* minimum_stride */
   -1			/* default_opt_level  */
 };
 
@@ -10608,16 +10596,6 @@ aarch64_override_options_internal (struct gcc_options *opts)
 			   aarch64_tune_params.prefetch->l2_cache_size,
 			   opts->x_param_values,
 			   global_options_set.x_param_values);
-  if (!aarch64_tune_params.prefetch->prefetch_dynamic_strides)
-    maybe_set_param_value (PARAM_PREFETCH_DYNAMIC_STRIDES,
-			   0,
-			   opts->x_param_values,
-			   global_options_set.x_param_values);
-  if (aarch64_tune_params.prefetch->minimum_stride >= 0)
-    maybe_set_param_value (PARAM_PREFETCH_MINIMUM_STRIDE,
-			   aarch64_tune_params.prefetch->minimum_stride,
-			   opts->x_param_values,
-			   global_options_set.x_param_values);
 
   /* Use the alternative scheduling-pressure algorithm by default.  */
   maybe_set_param_value (PARAM_SCHED_PRESSURE_ALGORITHM, SCHED_PRESSURE_MODEL,
diff --git a/gcc/doc/invoke.texi b/gcc/doc/invoke.texi
index 7e57e9650f6..255149fcfb8 100644
--- a/gcc/doc/invoke.texi
+++ b/gcc/doc/invoke.texi
@@ -10733,31 +10733,6 @@ The size of L1 cache, in kilobytes.
 @item l2-cache-size
 The size of L2 cache, in kilobytes.
 
-@item prefetch-dynamic-strides
-Whether the loop array prefetch pass should issue software prefetch hints
-for strides that are non-constant.  In some cases this may be
-beneficial, though the fact the stride is non-constant may make it
-hard to predict when there is clear benefit to issuing these hints.
-
-Set to 1, the default, if the prefetch hints should be issued for non-constant
-strides.  Set to 0 if prefetch hints should be issued only for strides that
-are known to be constant and below @option{prefetch-minimum-stride}.
-
-@item prefetch-minimum-stride
-Minimum constant stride, in bytes, to start using prefetch hints for.  If
-the stride is less than this threshold, prefetch hints will not be issued.
-
-This setting is useful for processors that have hardware prefetchers, in
-which case there may be conflicts between the hardware prefetchers and
-the software prefetchers.  If the hardware prefetchers have a maximum
-stride they can handle, it should be used here to improve the use of
-software prefetchers.
-
-A value of -1, the default, means we don't have a threshold and therefore
-prefetch hints can be issued for any constant stride.
-
-This setting is only useful for strides that are known and constant.
-
 @item loop-interchange-max-num-stmts
 The maximum number of stmts in a loop to be interchanged.
 
diff --git a/gcc/params.def b/gcc/params.def
index 7408843c8cc..dad47ec2b00 100644
--- a/gcc/params.def
+++ b/gcc/params.def
@@ -790,24 +790,6 @@ DEFPARAM (PARAM_L2_CACHE_SIZE,
 	  "The size of L2 cache.",
 	  512, 0, 0)
 
-/* Whether software prefetch hints should be issued for non-constant
-   strides.  */
-
-DEFPARAM (PARAM_PREFETCH_DYNAMIC_STRIDES,
-	  "prefetch-dynamic-strides",
-	  "Whether software prefetch hints should be issued for non-constant "
-	  "strides.",
-	  1, 0, 1)
-
-/* The minimum constant stride beyond which we should use prefetch hints
-   for.  */
-
-DEFPARAM (PARAM_PREFETCH_MINIMUM_STRIDE,
-	  "prefetch-minimum-stride",
-	  "The minimum constant stride beyond which we should use prefetch "
-	  "hints for.",
-	  -1, 0, 0)
-
 /* Maximum number of statements in loop nest for loop interchange.  */
 
 DEFPARAM (PARAM_LOOP_INTERCHANGE_MAX_NUM_STMTS,
diff --git a/gcc/params.h b/gcc/params.h
index 8aa960a904e..98249d2a1f6 100644
--- a/gcc/params.h
+++ b/gcc/params.h
@@ -196,10 +196,6 @@ extern void init_param_values (int *params);
   PARAM_VALUE (PARAM_L1_CACHE_LINE_SIZE)
 #define L2_CACHE_SIZE \
   PARAM_VALUE (PARAM_L2_CACHE_SIZE)
-#define PREFETCH_DYNAMIC_STRIDES \
-  PARAM_VALUE (PARAM_PREFETCH_DYNAMIC_STRIDES)
-#define PREFETCH_MINIMUM_STRIDE \
-  PARAM_VALUE (PARAM_PREFETCH_MINIMUM_STRIDE)
 #define USE_CANONICAL_TYPES \
   PARAM_VALUE (PARAM_USE_CANONICAL_TYPES)
 #define IRA_MAX_LOOPS_NUM \
diff --git a/gcc/tree-ssa-loop-prefetch.c b/gcc/tree-ssa-loop-prefetch.c
index af89d7070e3..2f10db18590 100644
--- a/gcc/tree-ssa-loop-prefetch.c
+++ b/gcc/tree-ssa-loop-prefetch.c
@@ -992,32 +992,6 @@ prune_by_reuse (struct mem_ref_group *groups)
 static bool
 should_issue_prefetch_p (struct mem_ref *ref)
 {
-  /* Do we want to issue prefetches for non-constant strides?  */
-  if (!cst_and_fits_in_hwi (ref->group->step) && PREFETCH_DYNAMIC_STRIDES == 0)
-    {
-      if (dump_file && (dump_flags & TDF_DETAILS))
-	fprintf (dump_file,
-		 "Skipping non-constant step for reference %u:%u\n",
-		 ref->group->uid, ref->uid);
-      return false;
-    }
-
-  /* Some processors may have a hardware prefetcher that may conflict with
-     prefetch hints for a range of strides.  Make sure we don't issue
-     prefetches for such cases if the stride is within this particular
-     range.  */
-  if (cst_and_fits_in_hwi (ref->group->step)
-      && absu_hwi (int_cst_value (ref->group->step)) < PREFETCH_MINIMUM_STRIDE)
-    {
-      if (dump_file && (dump_flags & TDF_DETAILS))
-	fprintf (dump_file,
-		 "Step for reference %u:%u (%d) is less than the mininum "
-		 "required stride of %d\n",
-		 ref->group->uid, ref->uid, int_cst_value (ref->group->step),
-		 PREFETCH_MINIMUM_STRIDE);
-      return false;
-    }
-
   /* For now do not issue prefetches for only first few of the
      iterations.  */
   if (ref->prefetch_before != PREFETCH_ALL)