[Clang][SVE2.1] Add pfalse builtin

[CarolineConcatto]

Summary

As described in: https://github.com/ARM-software/acle/pull/257

Patch by : Sander de Smalen<[e-mail]>

[CarolineConcatto]

-Rebase

[dtemirbulatov]

LGTM.

[CarolineConcatto]

-Rebase

clang/include/clang/Basic/arm_sve.td

 def SVBEXT_N : SInst<"svbext[_n_{d}]", "dda", "UcUsUiUl", MergeNone, "aarch64_sve_bext_x">;
 def SVBGRP   : SInst<"svbgrp[_{d}]",   "ddd", "UcUsUiUl", MergeNone, "aarch64_sve_bgrp_x">;
 def SVBGRP_N : SInst<"svbgrp[_n_{d}]", "dda", "UcUsUiUl", MergeNone, "aarch64_sve_bgrp_x">;
 }
 
 let TargetGuard = "sve2p1" in {
 def SVFCLAMP   : SInst<"svclamp[_{d}]", "dddd", "hfd", MergeNone, "aarch64_sve_fclamp", [], []>;
 def SVPTRUE_COUNT  : SInst<"svptrue_{d}", "}v", "QcQsQiQl", MergeNone, "aarch64_sve_ptrue_{d}", [IsOverloadNone], []>;
+def SVPFALSE_COUNT_ALIAS : SInst<"svpfalse_c", "}v", "", MergeNone, "", [IsOverloadNone]>;
 
 def SVPEXT_SINGLE : SInst<"svpext_lane_{d}", "P}i", "QcQsQiQl", MergeNone, "aarch64_sve_pext", [], [ImmCheck<1, ImmCheck0_3>]>;
 def SVPEXT_X2     : SInst<"svpext_lane_{d}_x2", "2.P}i", "QcQsQiQl", MergeNone, "aarch64_sve_pext_x2", [], [ImmCheck<1, ImmCheck0_1>]>;
 
 def SVPSEL_COUNT_ALIAS_B : SInst<"svpsel_lane_c8",  "}}Pm", "Pc", MergeNone, "", [], []>;
 def SVPSEL_COUNT_ALIAS_H : SInst<"svpsel_lane_c16", "}}Pm", "Ps", MergeNone, "", [], []>;
 def SVPSEL_COUNT_ALIAS_S : SInst<"svpsel_lane_c32", "}}Pm", "Pi", MergeNone, "", [], []>;
 def SVPSEL_COUNT_ALIAS_D : SInst<"svpsel_lane_c64", "}}Pm", "Pl", MergeNone, "", [], []>;

clang/lib/CodeGen/CGBuiltin.cpp

case SVE::BI__builtin_sve_svdupq_n_s32: {
     Value *Call = Builder.CreateCall(
         F, {Pred, DupQLane, EmitSVEDupX(Builder.getInt64(0))});
     return EmitSVEPredicateCast(Call, cast<llvm::ScalableVectorType>(Ty));
   }
 
   case SVE::BI__builtin_sve_svpfalse_b:
     return ConstantInt::getFalse(Ty);
 
+  case SVE::BI__builtin_sve_svpfalse_c: {
+    auto SVBoolTy = ScalableVectorType::get(Builder.getInt1Ty(), 16);
+    Function *CastToSVCountF =
+        CGM.getIntrinsic(Intrinsic::aarch64_sve_convert_from_svbool, Ty);
+    return Builder.CreateCall(CastToSVCountF, ConstantInt::getFalse(SVBoolTy));
+  }
+
   case SVE::BI__builtin_sve_svlen_bf16:
   case SVE::BI__builtin_sve_svlen_f16:
   case SVE::BI__builtin_sve_svlen_f32:
   case SVE::BI__builtin_sve_svlen_f64:
   case SVE::BI__builtin_sve_svlen_s8:
   case SVE::BI__builtin_sve_svlen_s16:
   case SVE::BI__builtin_sve_svlen_s32:
   case SVE::BI__builtin_sve_svlen_s64:

clang/test/CodeGen/aarch64-sve2p1-intrinsics/acle_sve2p1_pfalse.c

+// NOTE: Assertions have been autogenerated by utils/update_cc_test_checks.py
+// REQUIRES: aarch64-registered-target
+// RUN: %clang_cc1 -triple aarch64-none-linux-gnu -target-feature +sve2p1 -S -disable-O0-optnone -Werror -Wall -emit-llvm -o - %s | opt -S -passes=mem2reg,tailcallelim | FileCheck %s
+// RUN: %clang_cc1 -triple aarch64-none-linux-gnu -target-feature +sve2p1 -S -disable-O0-optnone -Werror -Wall -emit-llvm -o - -x c++ %s | opt -S -passes=mem2reg,tailcallelim | FileCheck %s -check-prefix=CPP-CHECK
+// RUN: %clang_cc1 -DSVE_OVERLOADED_FORMS -triple aarch64-none-linux-gnu -target-feature +sve2p1 -S -disable-O0-optnone -Werror -Wall -emit-llvm -o - %s | opt -S -passes=mem2reg,tailcallelim | FileCheck %s
+// RUN: %clang_cc1 -DSVE_OVERLOADED_FORMS -triple aarch64-none-linux-gnu -target-feature +sve2p1 -S -disable-O0-optnone -Werror -Wall -emit-llvm -o - -x c++ %s | opt -S -passes=mem2reg,tailcallelim | FileCheck %s -check-prefix=CPP-CHECK
+// RUN: %clang_cc1 -triple aarch64-none-linux-gnu -target-feature +sve2p1 -S -disable-O0-optnone -Werror -Wall -o /dev/null %s
+#include <arm_sve.h>
+
+#ifdef SVE_OVERLOADED_FORMS
+// A simple used,unused... macro, long enough to represent any SVE builtin.
+#define SVE_ACLE_FUNC(A1,A2_UNUSED,A3,A4_UNUSED) A1##A3
+#else
+#define SVE_ACLE_FUNC(A1,A2,A3,A4) A1##A2##A3##A4
+#endif
+
+// CHECK-LABEL: @test_svpfalse_c(
+// CHECK-NEXT:  entry:
+// CHECK-NEXT:    [[TMP0:%.*]] = tail call target("aarch64.svcount") @llvm.aarch64.sve.convert.from.svbool.taarch64.svcountt(<vscale x 16 x i1> zeroinitializer)
+// CHECK-NEXT:    ret target("aarch64.svcount") [[TMP0]]
+//
+// CPP-CHECK-LABEL: @_Z15test_svpfalse_cv(
+// CPP-CHECK-NEXT:  entry:
+// CPP-CHECK-NEXT:    [[TMP0:%.*]] = tail call target("aarch64.svcount") @llvm.aarch64.sve.convert.from.svbool.taarch64.svcountt(<vscale x 16 x i1> zeroinitializer)
+// CPP-CHECK-NEXT:    ret target("aarch64.svcount") [[TMP0]]
+//
+svcount_t test_svpfalse_c()
+{
+  return SVE_ACLE_FUNC(svpfalse_c,,,)();
+}