[PowerPC] Support of ppc_fp128 in lowering of llvm.is_fpclass

[sepavloff]

Summary

PowerPC supports ppc_fp128, which is not an IEEE floating point
type. The generic lowering of llvm.is_fpclass could not handle it
properly. This change extends the generic lowering code to
support ppc_fp128.

The change was tested on emulator using runtime tests from
https://reviews.llvm.org/D112933 and the patch for clang
https://reviews.llvm.org/D112932.

[qiucf]

llvm/test/CodeGen/PowerPC/ppc-is_fpclass.ll

3 ↗

(On Diff #387289)

Can you please add test case for fp128 type (under -mcpu=power9)?

And seems we don't need ppc- prefix in filename.

[sepavloff]

Updated patch

• In the test file name the prefix ppc- is dropped,
• The test now is compiled for POWER9
• The revision is retitled.

[qiucf]

Thanks

[sepavloff]

Thanks!

llvm/lib/CodeGen/SelectionDAG/TargetLowering.cpp

SDValue TargetLowering::expandIS_FPCLASS(EVT ResultVT, SDValue Op,
                                          SelectionDAG &DAG) const {
   EVT OperandVT = Op.getValueType();
   assert(OperandVT.isFloatingPoint());
 
   // Degenerated cases.
   if (Test == 0 || (Test & fcAllFlags) == fcAllFlags)
     return DAG.getBoolConstant(true, DL, ResultVT, OperandVT);
 
+  // PPC double double is a pair of doubles, of which the higher part determines
+  // the value class.
+  if (OperandVT == MVT::ppcf128) {
+    Op = DAG.getNode(ISD::EXTRACT_ELEMENT, DL, MVT::f64, Op,
+                     DAG.getConstant(1, DL, MVT::i32));
+    OperandVT = MVT::f64;
+  }
+
   // Some checks may be represented as inversion of simpler check, for example
   // "inf|normal|subnormal|zero" => !"nan".
   bool IsInverted = false;
   if (unsigned InvertedCheck = getInvertedFPClassTest(Test)) {
     IsInverted = true;
     Test = InvertedCheck;
   }
 

llvm/test/CodeGen/PowerPC/is_fpclass.ll

+; NOTE: Assertions have been autogenerated by utils/update_llc_test_checks.py
+; RUN: llc -mtriple=powerpc64le-unknown-linux-gnu -mcpu=pwr9 -verify-machineinstrs -o - %s | FileCheck %s
+
+
+define i1 @isnan_float(float %x) nounwind {
+; CHECK-LABEL: isnan_float:
+; CHECK:       # %bb.0:
+; CHECK-NEXT:    fcmpu 0, 1, 1
+; CHECK-NEXT:    li 3, 0
+; CHECK-NEXT:    li 4, 1
+; CHECK-NEXT:    isel 3, 4, 3, 3
+; CHECK-NEXT:    blr
+  %1 = call i1 @llvm.is.fpclass.f32(float %x, i32 3)  ; nan
+  ret i1 %1
+}
+
+define i1 @isnan_double(double %x) nounwind {
+; CHECK-LABEL: isnan_double:
+; CHECK:       # %bb.0:
+; CHECK-NEXT:    fcmpu 0, 1, 1
+; CHECK-NEXT:    li 3, 0
+; CHECK-NEXT:    li 4, 1
+; CHECK-NEXT:    isel 3, 4, 3, 3
+; CHECK-NEXT:    blr
+  %1 = call i1 @llvm.is.fpclass.f64(double %x, i32 3)  ; nan
+  ret i1 %1
+}
+
+define i1 @isnan_ppc_fp128(ppc_fp128 %x) nounwind {
+; CHECK-LABEL: isnan_ppc_fp128:
+; CHECK:       # %bb.0:
+; CHECK-NEXT:    fcmpu 0, 1, 1
+; CHECK-NEXT:    li 3, 0
+; CHECK-NEXT:    li 4, 1
+; CHECK-NEXT:    isel 3, 4, 3, 3
+; CHECK-NEXT:    blr
+  %1 = call i1 @llvm.is.fpclass.ppcf128(ppc_fp128 %x, i32 3)  ; nan
+  ret i1 %1
+}
+
+define i1 @isnan_f128(fp128 %x) nounwind {
+; CHECK-LABEL: isnan_f128:
+; CHECK:       # %bb.0:
+; CHECK-NEXT:    xscmpuqp 0, 2, 2
+; CHECK-NEXT:    li 3, 0
+; CHECK-NEXT:    li 4, 1
+; CHECK-NEXT:    isel 3, 4, 3, 3
+; CHECK-NEXT:    blr
+  %1 = call i1 @llvm.is.fpclass.f128(fp128 %x, i32 3)  ; nan
+  ret i1 %1
+}
+
+define i1 @isnan_float_strictfp(float %x) strictfp nounwind {
+; CHECK-LABEL: isnan_float_strictfp:
+; CHECK:       # %bb.0:
+; CHECK-NEXT:    xscvdpspn 0, 1
+; CHECK-NEXT:    lis 4, 32640
+; CHECK-NEXT:    mffprwz 3, 0
+; CHECK-NEXT:    clrlwi 3, 3, 1
+; CHECK-NEXT:    cmpw 3, 4
+; CHECK-NEXT:    li 3, 0
+; CHECK-NEXT:    li 4, 1
+; CHECK-NEXT:    iselgt 3, 4, 3
+; CHECK-NEXT:    blr
+  %1 = call i1 @llvm.is.fpclass.f32(float %x, i32 3)  ; nan
+  ret i1 %1
+}
+
+define i1 @isnan_double_strictfp(double %x) strictfp nounwind {
+; CHECK-LABEL: isnan_double_strictfp:
+; CHECK:       # %bb.0:
+; CHECK-NEXT:    mffprd 3, 1
+; CHECK-NEXT:    li 4, 2047
+; CHECK-NEXT:    clrldi 3, 3, 1
+; CHECK-NEXT:    rldic 4, 4, 52, 1
+; CHECK-NEXT:    cmpd 3, 4
+; CHECK-NEXT:    li 3, 0
+; CHECK-NEXT:    li 4, 1
+; CHECK-NEXT:    iselgt 3, 4, 3
+; CHECK-NEXT:    blr
+  %1 = call i1 @llvm.is.fpclass.f64(double %x, i32 3)  ; nan
+  ret i1 %1
+}
+
+define i1 @isnan_ppc_fp128_strictfp(ppc_fp128 %x) strictfp nounwind {
+; CHECK-LABEL: isnan_ppc_fp128_strictfp:
+; CHECK:       # %bb.0:
+; CHECK-NEXT:    mffprd 3, 1
+; CHECK-NEXT:    li 4, 2047
+; CHECK-NEXT:    clrldi 3, 3, 1
+; CHECK-NEXT:    rldic 4, 4, 52, 1
+; CHECK-NEXT:    cmpd 3, 4
+; CHECK-NEXT:    li 3, 0
+; CHECK-NEXT:    li 4, 1
+; CHECK-NEXT:    iselgt 3, 4, 3
+; CHECK-NEXT:    blr
+  %1 = call i1 @llvm.is.fpclass.ppcf128(ppc_fp128 %x, i32 3)  ; nan
+  ret i1 %1
+}
+
+define i1 @isnan_f128_strictfp(fp128 %x) strictfp nounwind {
+; CHECK-LABEL: isnan_f128_strictfp:
+; CHECK:       # %bb.0:
+; CHECK-NEXT:    stxv 34, -16(1)
+; CHECK-NEXT:    li 5, 32767
+; CHECK-NEXT:    ld 4, -8(1)
+; CHECK-NEXT:    ld 3, -16(1)
+; CHECK-NEXT:    rldic 5, 5, 48, 1
+; CHECK-NEXT:    clrldi 4, 4, 1
+; CHECK-NEXT:    cmpld 4, 5
+; CHECK-NEXT:    cmpd 1, 4, 5
+; CHECK-NEXT:    crandc 20, 5, 2
+; CHECK-NEXT:    cmpdi 1, 3, 0
+; CHECK-NEXT:    li 3, 1
+; CHECK-NEXT:    crandc 21, 2, 6
+; CHECK-NEXT:    crnor 20, 21, 20
+; CHECK-NEXT:    isel 3, 0, 3, 20
+; CHECK-NEXT:    blr
+  %1 = call i1 @llvm.is.fpclass.f128(fp128 %x, i32 3)  ; nan
+  ret i1 %1
+}
+
+define i1 @isinf_float(float %x) nounwind {
+; CHECK-LABEL: isinf_float:
+; CHECK:       # %bb.0:
+; CHECK-NEXT:    xscvdpspn 0, 1
+; CHECK-NEXT:    li 4, 1
+; CHECK-NEXT:    mffprwz 3, 0
+; CHECK-NEXT:    clrlwi 3, 3, 1
+; CHECK-NEXT:    xoris 3, 3, 32640
+; CHECK-NEXT:    cmplwi 3, 0
+; CHECK-NEXT:    li 3, 0
+; CHECK-NEXT:    iseleq 3, 4, 3
+; CHECK-NEXT:    blr
+  %1 = call i1 @llvm.is.fpclass.f32(float %x, i32 516)  ; 0x204 = "inf"
+  ret i1 %1
+}
+
+define i1 @isinf_ppc_fp128(ppc_fp128 %x) nounwind {
+; CHECK-LABEL: isinf_ppc_fp128:
+; CHECK:       # %bb.0:
+; CHECK-NEXT:    mffprd 3, 1
+; CHECK-NEXT:    li 4, 2047
+; CHECK-NEXT:    clrldi 3, 3, 1
+; CHECK-NEXT:    rldic 4, 4, 52, 1
+; CHECK-NEXT:    cmpd 3, 4
+; CHECK-NEXT:    li 3, 0
+; CHECK-NEXT:    li 4, 1
+; CHECK-NEXT:    iseleq 3, 4, 3
+; CHECK-NEXT:    blr
+  %1 = call i1 @llvm.is.fpclass.ppcf128(ppc_fp128 %x, i32 516)  ; 0x204 = "inf"
+  ret i1 %1
+}
+
+define i1 @isinf_f128(fp128 %x) nounwind {
+; CHECK-LABEL: isinf_f128:
+; CHECK:       # %bb.0:
+; CHECK-NEXT:    stxv 34, -16(1)
+; CHECK-NEXT:    li 5, 32767
+; CHECK-NEXT:    ld 4, -8(1)
+; CHECK-NEXT:    ld 3, -16(1)
+; CHECK-NEXT:    rldic 5, 5, 48, 1
+; CHECK-NEXT:    clrldi 4, 4, 1
+; CHECK-NEXT:    xor 4, 4, 5
+; CHECK-NEXT:    or 3, 3, 4
+; CHECK-NEXT:    cntlzd 3, 3
+; CHECK-NEXT:    rldicl 3, 3, 58, 63
+; CHECK-NEXT:    blr
+  %1 = call i1 @llvm.is.fpclass.f128(fp128 %x, i32 516)  ; 0x204 = "inf"
+  ret i1 %1
+}
+
+define i1 @isfinite_float(float %x) nounwind {
+; CHECK-LABEL: isfinite_float:
+; CHECK:       # %bb.0:
+; CHECK-NEXT:    xscvdpspn 0, 1
+; CHECK-NEXT:    lis 4, 32640
+; CHECK-NEXT:    mffprwz 3, 0
+; CHECK-NEXT:    clrlwi 3, 3, 1
+; CHECK-NEXT:    cmpw 3, 4
+; CHECK-NEXT:    li 3, 0
+; CHECK-NEXT:    li 4, 1
+; CHECK-NEXT:    isellt 3, 4, 3
+; CHECK-NEXT:    blr
+  %1 = call i1 @llvm.is.fpclass.f32(float %x, i32 504)  ; 0x1f8 = "finite"
+  ret i1 %1
+}
+
+define i1 @isfinite_f128(fp128 %x) nounwind {
+; CHECK-LABEL: isfinite_f128:
+; CHECK:       # %bb.0:
+; CHECK-NEXT:    stxv 34, -16(1)
+; CHECK-NEXT:    li 4, 32767
+; CHECK-NEXT:    ld 3, -8(1)
+; CHECK-NEXT:    rldic 4, 4, 48, 1
+; CHECK-NEXT:    clrldi 3, 3, 1
+; CHECK-NEXT:    cmpd 3, 4
+; CHECK-NEXT:    li 3, 0
+; CHECK-NEXT:    li 4, 1
+; CHECK-NEXT:    isellt 3, 4, 3
+; CHECK-NEXT:    blr
+  %1 = call i1 @llvm.is.fpclass.f128(fp128 %x, i32 504)  ; 0x1f8 = "finite"
+  ret i1 %1
+}
+
+define i1 @isnormal_float(float %x) nounwind {
+; CHECK-LABEL: isnormal_float:
+; CHECK:       # %bb.0:
+; CHECK-NEXT:    xscvdpspn 0, 1
+; CHECK-NEXT:    li 4, 1
+; CHECK-NEXT:    mffprwz 3, 0
+; CHECK-NEXT:    clrlwi 3, 3, 1
+; CHECK-NEXT:    addis 3, 3, -128
+; CHECK-NEXT:    srwi 3, 3, 24
+; CHECK-NEXT:    cmplwi 3, 127
+; CHECK-NEXT:    li 3, 0
+; CHECK-NEXT:    isellt 3, 4, 3
+; CHECK-NEXT:    blr
+  %1 = call i1 @llvm.is.fpclass.f32(float %x, i32 264)  ; 0x108 = "normal"
+  ret i1 %1
+}
+
+define i1 @isnormal_f128(fp128 %x) nounwind {
+; CHECK-LABEL: isnormal_f128:
+; CHECK:       # %bb.0:
+; CHECK-NEXT:    stxv 34, -16(1)
+; CHECK-NEXT:    li 4, -1
+; CHECK-NEXT:    ld 3, -8(1)
+; CHECK-NEXT:    rldic 4, 4, 48, 0
+; CHECK-NEXT:    clrldi 3, 3, 1
+; CHECK-NEXT:    add 3, 3, 4
+; CHECK-NEXT:    li 4, 1
+; CHECK-NEXT:    rldicl 3, 3, 15, 49
+; CHECK-NEXT:    cmpldi 3, 16383
+; CHECK-NEXT:    li 3, 0
+; CHECK-NEXT:    isellt 3, 4, 3
+; CHECK-NEXT:    blr
+  %1 = call i1 @llvm.is.fpclass.f128(fp128 %x, i32 264)  ; 0x108 = "normal"
+  ret i1 %1
+}
+
+define i1 @issubnormal_float(float %x) nounwind {
+; CHECK-LABEL: issubnormal_float:
+; CHECK:       # %bb.0:
+; CHECK-NEXT:    xscvdpspn 0, 1
+; CHECK-NEXT:    lis 4, 127
+; CHECK-NEXT:    ori 4, 4, 65535
+; CHECK-NEXT:    mffprwz 3, 0
+; CHECK-NEXT:    clrlwi 3, 3, 1
+; CHECK-NEXT:    addi 3, 3, -1
+; CHECK-NEXT:    cmplw 3, 4
+; CHECK-NEXT:    li 3, 0
+; CHECK-NEXT:    li 4, 1
+; CHECK-NEXT:    isellt 3, 4, 3
+; CHECK-NEXT:    blr
+  %1 = call i1 @llvm.is.fpclass.f32(float %x, i32 144)  ; 0x90 = "subnormal"
+  ret i1 %1
+}
+
+define i1 @issubnormal_f128(fp128 %x) nounwind {
+; CHECK-LABEL: issubnormal_f128:
+; CHECK:       # %bb.0:
+; CHECK-NEXT:    stxv 34, -16(1)
+; CHECK-NEXT:    li 5, -1
+; CHECK-NEXT:    ld 4, -8(1)
+; CHECK-NEXT:    ld 3, -16(1)
+; CHECK-NEXT:    rldic 5, 5, 0, 16
+; CHECK-NEXT:    clrldi 4, 4, 1
+; CHECK-NEXT:    addic 3, 3, -1
+; CHECK-NEXT:    addme 4, 4
+; CHECK-NEXT:    cmpdi 1, 3, -1
+; CHECK-NEXT:    li 3, 1
+; CHECK-NEXT:    cmpld 4, 5
+; CHECK-NEXT:    crandc 20, 0, 2
+; CHECK-NEXT:    crandc 21, 2, 6
+; CHECK-NEXT:    crnor 20, 21, 20
+; CHECK-NEXT:    isel 3, 0, 3, 20
+; CHECK-NEXT:    blr
+  %1 = call i1 @llvm.is.fpclass.f128(fp128 %x, i32 144)  ; 0x90 = "subnormal"
+  ret i1 %1
+}
+
+define i1 @iszero_float(float %x) nounwind {
+; CHECK-LABEL: iszero_float:
+; CHECK:       # %bb.0:
+; CHECK-NEXT:    xxlxor 0, 0, 0
+; CHECK-NEXT:    li 3, 0
+; CHECK-NEXT:    li 4, 1
+; CHECK-NEXT:    fcmpu 0, 1, 0
+; CHECK-NEXT:    iseleq 3, 4, 3
+; CHECK-NEXT:    blr
+  %1 = call i1 @llvm.is.fpclass.f32(float %x, i32 96)  ; 0x60 = "zero"
+  ret i1 %1
+}
+
+define i1 @iszero_f128(fp128 %x) nounwind {
+; CHECK-LABEL: iszero_f128:
+; CHECK:       # %bb.0:
+; CHECK-NEXT:    addis 3, 2, .LCPI18_0@toc@ha
+; CHECK-NEXT:    li 4, 1
+; CHECK-NEXT:    addi 3, 3, .LCPI18_0@toc@l
+; CHECK-NEXT:    lxv 35, 0(3)
+; CHECK-NEXT:    li 3, 0
+; CHECK-NEXT:    xscmpuqp 0, 2, 3
+; CHECK-NEXT:    iseleq 3, 4, 3
+; CHECK-NEXT:    blr
+  %1 = call i1 @llvm.is.fpclass.f128(fp128 %x, i32 96)  ; 0x60 = "zero"
+  ret i1 %1
+}
+
+declare i1 @llvm.is.fpclass.f32(float, i32)
+declare i1 @llvm.is.fpclass.f64(double, i32)
+declare i1 @llvm.is.fpclass.ppcf128(ppc_fp128, i32)
+declare i1 @llvm.is.fpclass.f128(fp128, i32)