[arm][2/X] Implement __qadd, __qsub, __qdbl intrinsics

This patch implements some more Q-bit-setting intrinsics from ACLE.
With the plumbing from patch 1 in place they are a simple builtin->RTL
affair.

	* config/arm/arm.md (arm_<ss_op>): New define_expand.
	(arm_<ss_op><add_clobber_q_name>_insn): New define_insn.
	* config/arm/arm_acle.h (__qadd, __qsub, __qdbl): Define.
	* config/arm/arm_acle_builtins.def: Add builtins for qadd, qsub.
	* config/arm/iterators.md (SSPLUSMINUS): New code iterator.
	(ss_op): New code_attr.

	* gcc.target/arm/acle/dsp_arith.c: New test.

From-SVN: r277915

gcc/ChangeLog

 2019-11-07  Kyrylo Tkachov  <kyrylo.tkachov@arm.com>
 
+	* config/arm/arm.md (arm_<ss_op>): New define_expand.
+	(arm_<ss_op><add_clobber_q_name>_insn): New define_insn.
+	* config/arm/arm_acle.h (__qadd, __qsub, __qdbl): Define.
+	* config/arm/arm_acle_builtins.def: Add builtins for qadd, qsub.
+	* config/arm/iterators.md (SSPLUSMINUS): New code iterator.
+	(ss_op): New code_attr.
+
+2019-11-07  Kyrylo Tkachov  <kyrylo.tkachov@arm.com>
+
 	* config/arm/aout.h (REGISTER_NAMES): Add apsrq.
 	* config/arm/arm.md (APSRQ_REGNUM): Define.
 	(add_setq): New define_subst.

gcc/config/arm/arm.md

@@ -4076,6 +4076,32 @@
    (set_attr "type" "multiple")]
 )
 
+
+(define_expand "arm_<ss_op>"
+  [(set (match_operand:SI 0 "s_register_operand")
+	(SSPLUSMINUS:SI (match_operand:SI 1 "s_register_operand")
+			(match_operand:SI 2 "s_register_operand")))]
+  "TARGET_DSP_MULTIPLY"
+  {
+    if (ARM_Q_BIT_READ)
+      emit_insn (gen_arm_<ss_op>_setq_insn (operands[0],
+					    operands[1], operands[2]));
+    else
+      emit_insn (gen_arm_<ss_op>_insn (operands[0], operands[1], operands[2]));
+    DONE;
+  }
+)
+
+(define_insn "arm_<ss_op><add_clobber_q_name>_insn"
+  [(set (match_operand:SI 0 "s_register_operand" "=r")
+	(SSPLUSMINUS:SI (match_operand:SI 1 "s_register_operand" "r")
+			(match_operand:SI 2 "s_register_operand" "r")))]
+  "TARGET_DSP_MULTIPLY && <add_clobber_q_pred>"
+  "<ss_op>%?\t%0, %1, %2"
+  [(set_attr "predicable" "yes")
+   (set_attr "type" "alu_dsp_reg")]
+)
+
 (define_code_iterator SAT [smin smax])
 (define_code_attr SATrev [(smin "smax") (smax "smin")])
 (define_code_attr SATlo [(smin "1") (smax "2")])

gcc/config/arm/arm_acle.h

@@ -478,6 +478,29 @@ __ignore_saturation (void)
   })
 #endif
 
+#ifdef __ARM_FEATURE_DSP
+__extension__ extern __inline int32_t
+__attribute__  ((__always_inline__, __gnu_inline__, __artificial__))
+__qadd (int32_t __a, int32_t __b)
+{
+  return __builtin_arm_qadd (__a, __b);
+}
+
+__extension__ extern __inline int32_t
+__attribute__  ((__always_inline__, __gnu_inline__, __artificial__))
+__qsub (int32_t __a, int32_t __b)
+{
+  return __builtin_arm_qsub (__a, __b);
+}
+
+__extension__ extern __inline int32_t
+__attribute__  ((__always_inline__, __gnu_inline__, __artificial__))
+__qdbl (int32_t __x)
+{
+  return __qadd (__x, __x);
+}
+#endif
+
 #pragma GCC push_options
 #ifdef __ARM_FEATURE_CRC32
 #ifdef __ARM_FP

gcc/config/arm/arm_acle_builtins.def

@@ -84,3 +84,5 @@ VAR1 (SAT_BINOP_UNSIGNED_IMM, ssat, si)
 VAR1 (UNSIGNED_SAT_BINOP_UNSIGNED_IMM, usat, si)
 VAR1 (SAT_OCCURRED, saturation_occurred, si)
 VAR1 (SET_SAT, set_saturation, void)
+VAR1 (BINOP, qadd, si)
+VAR1 (BINOP, qsub, si)

gcc/config/arm/iterators.md

@@ -264,6 +264,9 @@
 ;; Conversions.
 (define_code_iterator FCVT [unsigned_float float])
 
+;; Saturating addition, subtraction
+(define_code_iterator SSPLUSMINUS [ss_plus ss_minus])
+
 ;; plus and minus are the only SHIFTABLE_OPS for which Thumb2 allows
 ;; a stack pointer operand.  The minus operation is a candidate for an rsub
 ;; and hence only plus is supported.
@@ -282,6 +285,8 @@
 
 (define_code_attr vfml_op [(plus "a") (minus "s")])
 
+(define_code_attr ss_op [(ss_plus "qadd") (ss_minus "qsub")])
+
 ;;----------------------------------------------------------------------------
 ;; Int iterators
 ;;----------------------------------------------------------------------------

gcc/testsuite/ChangeLog

 2019-11-07  Kyrylo Tkachov  <kyrylo.tkachov@arm.com>
 
+	* gcc.target/arm/acle/dsp_arith.c: New test.
+
+2019-11-07  Kyrylo Tkachov  <kyrylo.tkachov@arm.com>
+
 	* gcc.target/arm/acle/saturation.c: New test.
 	* gcc.target/arm/acle/sat_no_smlatb.c: Likewise.
 	* lib/target-supports.exp (check_effective_target_arm_qbit_ok_nocache):

gcc/testsuite/gcc.target/arm/acle/dsp_arith.c

+/* { dg-do compile } */
+/* { dg-require-effective-target arm_qbit_ok } */
+/* { dg-add-options arm_qbit  } */
+
+#include <arm_acle.h>
+
+int32_t
+test_qadd (int32_t a, int32_t b)
+{
+  return __qadd (a, b);
+}
+
+int32_t
+test_qdbl (int32_t a)
+{
+  return __qdbl(a);
+}
+
+/* { dg-final { scan-assembler-times "qadd\t...?, ...?, ...?" 2 } } */
+
+int32_t
+test_qsub (int32_t a, int32_t b)
+{
+  return __qsub (a, b);
+}
+
+/* { dg-final { scan-assembler-times "qsub\t...?, ...?, ...?" 1 } } */