Add IFN_COND_FMA functions

This patch adds conditional equivalents of the IFN_FMA built-in functions.
Most of it is just a mechanical extension of the binary stuff.

2018-07-12  Richard Sandiford  <richard.sandiford@linaro.org>

gcc/
	* doc/md.texi (cond_fma, cond_fms, cond_fnma, cond_fnms): Document.
	* optabs.def (cond_fma_optab, cond_fms_optab, cond_fnma_optab)
	(cond_fnms_optab): New optabs.
	* internal-fn.def (COND_FMA, COND_FMS, COND_FNMA, COND_FNMS): New
	internal functions.
	(FMA): Use DEF_INTERNAL_FLT_FN rather than DEF_INTERNAL_FLT_FLOATN_FN.
	* internal-fn.h (get_conditional_internal_fn): Declare.
	(get_unconditional_internal_fn): Likewise.
	* internal-fn.c (cond_ternary_direct): New macro.
	(expand_cond_ternary_optab_fn): Likewise.
	(direct_cond_ternary_optab_supported_p): Likewise.
	(FOR_EACH_COND_FN_PAIR): Likewise.
	(get_conditional_internal_fn): New function.
	(get_unconditional_internal_fn): Likewise.
	* gimple-match.h (gimple_match_op::MAX_NUM_OPS): Bump to 5.
	(gimple_match_op::gimple_match_op): Add a new overload for 5
	operands.
	(gimple_match_op::set_op): Likewise.
	(gimple_resimplify5): Declare.
	* genmatch.c (decision_tree::gen): Generate simplifications for
	5 operands.
	* gimple-match-head.c (gimple_simplify): Define an overload for
	5 operands.  Handle calls with 5 arguments in the top-level overload.
	(convert_conditional_op): Handle conversions from unconditional
	internal functions to conditional ones.
	(gimple_resimplify5): New function.
	(build_call_internal): Pass a fifth operand.
	(maybe_push_res_to_seq): Likewise.
	(try_conditional_simplification): Try converting conditional
	internal functions to unconditional internal functions.
	Handle 3-operand unconditional forms.
	* match.pd (UNCOND_TERNARY, COND_TERNARY): Operator lists.
	Define ternary equivalents of the current rules for binary conditional
	internal functions.
	* config/aarch64/aarch64.c (aarch64_preferred_else_value): Handle
	ternary operations.
	* config/aarch64/iterators.md (UNSPEC_COND_FMLA, UNSPEC_COND_FMLS)
	(UNSPEC_COND_FNMLA, UNSPEC_COND_FNMLS): New unspecs.
	(optab): Handle them.
	(SVE_COND_FP_TERNARY): New int iterator.
	(sve_fmla_op, sve_fmad_op): New int attributes.
	* config/aarch64/aarch64-sve.md (cond_<optab><mode>)
	(*cond_<optab><mode>_2, *cond_<optab><mode_4)
	(*cond_<optab><mode>_any): New SVE_COND_FP_TERNARY patterns.

gcc/testsuite/
	* gcc.dg/vect/vect-cond-arith-3.c: New test.
	* gcc.target/aarch64/sve/vcond_13.c: Likewise.
	* gcc.target/aarch64/sve/vcond_13_run.c: Likewise.
	* gcc.target/aarch64/sve/vcond_14.c: Likewise.
	* gcc.target/aarch64/sve/vcond_14_run.c: Likewise.
	* gcc.target/aarch64/sve/vcond_15.c: Likewise.
	* gcc.target/aarch64/sve/vcond_15_run.c: Likewise.
	* gcc.target/aarch64/sve/vcond_16.c: Likewise.
	* gcc.target/aarch64/sve/vcond_16_run.c: Likewise.


git-svn-id: https://gcc.gnu.org/svn/gcc/trunk@262587 138bc75d-0d04-0410-961f-82ee72b054a4

1 files changed, 56 insertions, 0 deletions

diff --git a/gcc/internal-fn.c b/gcc/internal-fn.c
index eb5493fcd81..474a16bc6fb 100644
--- a/gcc/internal-fn.c
+++ b/gcc/internal-fn.c
@@ -113,6 +113,7 @@ init_internal_fns ()
 #define ternary_direct { 0, 0, true }
 #define cond_unary_direct { 1, 1, true }
 #define cond_binary_direct { 1, 1, true }
+#define cond_ternary_direct { 1, 1, true }
 #define while_direct { 0, 2, false }
 #define fold_extract_direct { 2, 2, false }
 #define fold_left_direct { 1, 1, false }
@@ -2993,6 +2994,9 @@ expand_while_optab_fn (internal_fn, gcall *stmt, convert_optab optab)
 #define expand_cond_binary_optab_fn(FN, STMT, OPTAB) \
   expand_direct_optab_fn (FN, STMT, OPTAB, 4)
 
+#define expand_cond_ternary_optab_fn(FN, STMT, OPTAB) \
+  expand_direct_optab_fn (FN, STMT, OPTAB, 5)
+
 #define expand_fold_extract_optab_fn(FN, STMT, OPTAB) \
   expand_direct_optab_fn (FN, STMT, OPTAB, 3)
 
@@ -3075,6 +3079,7 @@ multi_vector_optab_supported_p (convert_optab optab, tree_pair types,
 #define direct_ternary_optab_supported_p direct_optab_supported_p
 #define direct_cond_unary_optab_supported_p direct_optab_supported_p
 #define direct_cond_binary_optab_supported_p direct_optab_supported_p
+#define direct_cond_ternary_optab_supported_p direct_optab_supported_p
 #define direct_mask_load_optab_supported_p direct_optab_supported_p
 #define direct_load_lanes_optab_supported_p multi_vector_optab_supported_p
 #define direct_mask_load_lanes_optab_supported_p multi_vector_optab_supported_p
@@ -3277,6 +3282,57 @@ conditional_internal_fn_code (internal_fn ifn)
     }
 }
 
+/* Invoke T(IFN) for each internal function IFN that also has an
+   IFN_COND_* form.  */
+#define FOR_EACH_COND_FN_PAIR(T) \
+  T (FMA) \
+  T (FMS) \
+  T (FNMA) \
+  T (FNMS)
+
+/* Return a function that only performs internal function FN when a
+   certain condition is met and that uses a given fallback value otherwise.
+   In other words, the returned function FN' is such that:
+
+     LHS = FN' (COND, A1, ... An, ELSE)
+
+   is equivalent to the C expression:
+
+     LHS = COND ? FN (A1, ..., An) : ELSE;
+
+   operating elementwise if the operands are vectors.
+
+   Return IFN_LAST if no such function exists.  */
+
+internal_fn
+get_conditional_internal_fn (internal_fn fn)
+{
+  switch (fn)
+    {
+#define CASE(NAME) case IFN_##NAME: return IFN_COND_##NAME;
+      FOR_EACH_COND_FN_PAIR(CASE)
+#undef CASE
+    default:
+      return IFN_LAST;
+    }
+}
+
+/* If IFN implements the conditional form of an unconditional internal
+   function, return that unconditional function, otherwise return IFN_LAST.  */
+
+internal_fn
+get_unconditional_internal_fn (internal_fn ifn)
+{
+  switch (ifn)
+    {
+#define CASE(NAME) case IFN_COND_##NAME: return IFN_##NAME;
+      FOR_EACH_COND_FN_PAIR(CASE)
+#undef CASE
+    default:
+      return IFN_LAST;
+    }
+}
+
 /* Return true if IFN is some form of load from memory.  */
 
 bool