[PowerPC] Add BCDCOPYSIGN and BCDSETSIGN Instruction Support (#144874)

Support the following BCD format conversion builtins for PowerPC.

- `__builtin_bcdcopysign` – Conversion that returns the decimal value of
the first parameter combined with the sign code of the second parameter.
`
- `__builtin_bcdsetsign` – Conversion that sets the sign code of the
input parameter in packed decimal format.

> Note: This built-in function is valid only when all following
conditions are met:
> -qarch is set to utilize POWER9 technology.
> The bcd.h file is included.

## Prototypes

```c
vector unsigned char __builtin_bcdcopysign(vector unsigned char, vector unsigned char);
vector unsigned char __builtin_bcdsetsign(vector unsigned char, unsigned char);
```

## Usage Details

`__builtin_bcdsetsign`: Returns the packed decimal value of the first
parameter combined with the sign code.
The sign code is set according to the following rules:
- If the packed decimal value of the first parameter is positive, the
following rules apply:
     - If the second parameter is 0, the sign code is set to 0xC.
     - If the second parameter is 1, the sign code is set to 0xF.
- If the packed decimal value of the first parameter is negative, the
sign code is set to 0xD.
> notes:
>     The second parameter can only be 0 or 1.
> You can determine whether a packed decimal value is positive or
negative as follows:
> - Packed decimal values with sign codes **0xA, 0xC, 0xE, or 0xF** are
interpreted as positive.
> - Packed decimal values with sign codes **0xB or 0xD** are interpreted
as negative.

---------

Co-authored-by: Aditi-Medhane <aditi.medhane@ibm.com>

Author: AditiRM

clang/include/clang/Basic/BuiltinsPPC.def

@@ -580,6 +580,8 @@ TARGET_BUILTIN(__builtin_ppc_bcdsub_p, "iiV16UcV16Uc", "",
                "isa-v207-instructions")
 
 // P9 Binary-coded decimal (BCD) builtins.                                                
+TARGET_BUILTIN(__builtin_ppc_bcdcopysign, "V16UcV16UcV16Uc", "", "power9-vector")
+TARGET_BUILTIN(__builtin_ppc_bcdsetsign, "V16UcV16UcUc", "t", "power9-vector")
 TARGET_BUILTIN(__builtin_ppc_national2packed, "V16UcV16UcUc", "t", "power9-vector")
 TARGET_BUILTIN(__builtin_ppc_packed2national, "V16UcV16Uc", "", "power9-vector")
 TARGET_BUILTIN(__builtin_ppc_packed2zoned, "V16UcV16UcUc", "t", "power9-vector")

clang/lib/Basic/Targets/PPC.cpp

@@ -89,6 +89,8 @@ bool PPCTargetInfo::handleTargetFeatures(std::vector<std::string> &Features,
 }
 
 static void defineXLCompatMacros(MacroBuilder &Builder) {
+  Builder.defineMacro("__builtin_bcdcopysign", "__builtin_ppc_bcdcopysign");
+  Builder.defineMacro("__builtin_bcdsetsign", "__builtin_ppc_bcdsetsign");
   Builder.defineMacro("__builtin_national2packed",
                       "__builtin_ppc_national2packed");
   Builder.defineMacro("__builtin_packed2national",

clang/lib/Sema/SemaPPC.cpp

@@ -108,6 +108,7 @@ bool SemaPPC::CheckPPCBuiltinFunctionCall(const TargetInfo &TI,
   switch (BuiltinID) {
   default:
     return false;
+  case PPC::BI__builtin_ppc_bcdsetsign:
   case PPC::BI__builtin_ppc_national2packed:
   case PPC::BI__builtin_ppc_packed2zoned:
   case PPC::BI__builtin_ppc_zoned2packed:

clang/test/CodeGen/PowerPC/builtins-bcd-format-conversion.c

@@ -0,0 +1,29 @@
+// NOTE: Assertions have been autogenerated by utils/update_llc_test_checks.py UTC_ARGS: --version 5
+// REQUIRES: powerpc-registered-target
+// RUN: %clang_cc1 -triple powerpc64le-unknown-unknown -O2 -target-cpu pwr9 \
+// RUN:   -emit-llvm %s -o - | FileCheck %s
+// RUN: %clang_cc1 -triple powerpc64-unknown-unknown -O2 -target-cpu pwr9 \
+// RUN:   -emit-llvm %s -o - | FileCheck %s
+// RUN: %clang_cc1 -triple powerpc-unknown-unknown -O2 -target-cpu pwr9 \
+// RUN:   -emit-llvm %s -o - | FileCheck %s
+
+// CHECK-LABEL: test_bcdcopysign
+// CHECK:         [[TMP0:%.*]] = tail call <16 x i8> @llvm.ppc.bcdcopysign(<16 x i8> %a, <16 x i8> %b)
+// CHECK-NEXT:    ret <16 x i8> [[TMP0]]
+vector unsigned char test_bcdcopysign(vector unsigned char a, vector unsigned char b) {
+    return __builtin_ppc_bcdcopysign(a, b);
+}
+
+// CHECK-LABEL: test_bcdsetsign_imm0
+// CHECK:         [[TMP0:%.*]] = tail call <16 x i8> @llvm.ppc.bcdsetsign(<16 x i8> %a, i32 0)
+// CHECK-NEXT:    ret <16 x i8> [[TMP0]]
+vector unsigned char test_bcdsetsign_imm0(vector unsigned char a) {
+    return __builtin_ppc_bcdsetsign(a, '\0');
+}
+
+// CHECK-LABEL: test_bcdsetsign_imm1
+// CHECK:         [[TMP0:%.*]] = tail call <16 x i8> @llvm.ppc.bcdsetsign(<16 x i8> %a, i32 1)
+// CHECK-NEXT:    ret <16 x i8> [[TMP0]]
+vector unsigned char test_bcdsetsign_imm1(vector unsigned char a) {
+    return __builtin_ppc_bcdsetsign(a, '\1');
+}

llvm/include/llvm/IR/IntrinsicsPowerPC.td

@@ -676,6 +676,13 @@ let TargetPrefix = "ppc" in {  // All intrinsics start with "llvm.ppc.".
   def int_ppc_addg6s: ClangBuiltin<"__builtin_addg6s">,
     DefaultAttrsIntrinsic<[llvm_i32_ty], [llvm_i32_ty, llvm_i32_ty], [IntrNoMem]>;
 
+  // BCD Format conversion intrinsics 
+  def int_ppc_bcdcopysign : ClangBuiltin<"__builtin_ppc_bcdcopysign">,
+    DefaultAttrsIntrinsic<[llvm_v16i8_ty], [llvm_v16i8_ty, llvm_v16i8_ty], [IntrNoMem]>; 
+  def int_ppc_bcdsetsign : ClangBuiltin<"__builtin_ppc_bcdsetsign">,
+    DefaultAttrsIntrinsic<[llvm_v16i8_ty], [llvm_v16i8_ty, llvm_i32_ty], 
+    [IntrNoMem, ImmArg<ArgIndex<1>>]>;
+
   def int_ppc_bcdadd : ClangBuiltin<"__builtin_ppc_bcdadd">,
     DefaultAttrsIntrinsic<
     [llvm_v16i8_ty], [llvm_v16i8_ty, llvm_v16i8_ty, llvm_i32_ty],

llvm/lib/Target/PowerPC/PPCInstrAltivec.td

@@ -1630,9 +1630,11 @@ def BCDCTSQ_rec : VX_VT5_EO5_VB5_XO9_o    <0, 385, "bcdctsq.", []>;
 
 // Decimal Copy-Sign/Set-Sign
 let Defs = [CR6] in
-def BCDCPSGN_rec : VX1_VT5_VA5_VB5<833, "bcdcpsgn.", []>;
+def BCDCPSGN_rec : VX1_VT5_VA5_VB5<833, "bcdcpsgn.",
+    [(set v16i8:$VD, (int_ppc_bcdcopysign v16i8:$VA, v16i8:$VB))]>;
 
-def BCDSETSGN_rec : VX_VT5_EO5_VB5_PS1_XO9_o<31, 385, "bcdsetsgn.", []>;
+def BCDSETSGN_rec : VX_VT5_EO5_VB5_PS1_XO9_o<31, 385, "bcdsetsgn.",
+    [(set v16i8:$VD, (int_ppc_bcdsetsign v16i8:$VB, i32:$PS))]>;
 
 // Decimal Shift/Unsigned-Shift/Shift-and-Round
 def BCDS_rec :  VX_VT5_VA5_VB5_PS1_XO9_o<193, "bcds." , []>;

llvm/test/CodeGen/PowerPC/builtins-bcd-format-conversion.ll

@@ -0,0 +1,40 @@
+; NOTE: Assertions have been autogenerated by utils/update_llc_test_checks.py UTC_ARGS: --version 5
+; RUN: llc -verify-machineinstrs -mtriple=powerpc64le-unknown-unknown -mcpu=pwr9 \
+; RUN:  --ppc-asm-full-reg-names < %s | FileCheck %s
+; RUN: llc -verify-machineinstrs -mtriple=powerpc64-unknown-unknown -mcpu=pwr9 \
+; RUN:     --ppc-asm-full-reg-names < %s | FileCheck %s
+; RUN: llc -verify-machineinstrs -mcpu=pwr9 -mtriple=powerpc64-ibm-aix-xcoff \
+; RUN:   -ppc-asm-full-reg-names  < %s | FileCheck %s
+
+define dso_local <16 x i8> @test_bcdcopysign(<16 x i8> noundef %a, <16 x i8> noundef %b) {
+; CHECK-LABEL: test_bcdcopysign:
+; CHECK:       # %bb.0: # %entry
+; CHECK-NEXT:    bcdcpsgn. v2, v2, v3
+; CHECK-NEXT:    blr
+entry:
+  %0 = tail call <16 x i8> @llvm.ppc.bcdcopysign(<16 x i8> %a, <16 x i8> %b)
+  ret <16 x i8> %0
+}
+
+define dso_local <16 x i8> @test_bcdsetsign_imm0(<16 x i8> noundef %a) {
+; CHECK-LABEL: test_bcdsetsign_imm0:
+; CHECK:       # %bb.0: # %entry
+; CHECK-NEXT:    bcdsetsgn. v2, v2, 0
+; CHECK-NEXT:    blr
+entry:
+  %0 = tail call <16 x i8> @llvm.ppc.bcdsetsign(<16 x i8> %a, i32 0)
+  ret <16 x i8> %0
+}
+
+define dso_local <16 x i8> @test_bcdsetsign_imm1(<16 x i8> noundef %a) {
+; CHECK-LABEL: test_bcdsetsign_imm1:
+; CHECK:       # %bb.0: # %entry
+; CHECK-NEXT:    bcdsetsgn. v2, v2, 1
+; CHECK-NEXT:    blr
+entry:
+  %0 = tail call <16 x i8> @llvm.ppc.bcdsetsign(<16 x i8> %a, i32 1)
+  ret <16 x i8> %0
+}
+
+declare <16 x i8> @llvm.ppc.bcdcopysign(<16 x i8>, <16 x i8>)
+declare <16 x i8> @llvm.ppc.bcdsetsign(<16 x i8>, i32)