[PATCH] D107082: [X86][RFC] Enable `_Float16` type support on X86 following the psABI

[Valentin Clement via Phabricator via llvm-commits]

clementval added a comment.

@pengfei We are also hitting the following assertion with this patch. Do you have any idea why?

  /llvm-project/llvm/lib/CodeGen/SelectionDAG/LegalizeDAG.cpp:4333: void {anonymous}::SelectionDAGLegalize::ConvertNodeToLibcall(llvm::SDNode*): Assertion `cast<ConstantSDNode>(Node->getOperand(IsStrict ? 2 : 1))->isZero() && "Unable to expand as libcall if it is not normal rounding"' failed.

LLVM IR triggering the assertion.

  ; ModuleID = 'FIRModule'
  source_filename = "FIRModule"
  target triple = "x86_64-unknown-linux-gnu"
  
  @_QMhp237Ea11 = global half 0xH3D00
  @_QMhp237Eb1a = global half 0xH5640
  @_QMf90_kindECascii = external constant i32
  @_QMf90_kindECbyte = external constant i32
  @_QMf90_kindECdouble = external constant i32
  @_QMiso_fortran_envECint16 = external constant i32
  @_QMiso_fortran_envECint32 = external constant i32
  @_QMiso_fortran_envECint64 = external constant i32
  @_QMiso_fortran_envECint8 = external constant i32
  @_QMf90_kindECjis = external constant i32
  @_QMiso_fortran_envEClogical16 = external constant i32
  @_QMiso_fortran_envEClogical32 = external constant i32
  @_QMiso_fortran_envEClogical64 = external constant i32
  @_QMiso_fortran_envEClogical8 = external constant i32
  @_QMf90_kindECnot_available = external constant i32
  @_QMf90_kindECquad = external constant i32
  @_QMiso_fortran_envECreal128 = external constant i32
  @_QMf90_kindECreal16 = external constant i32
  @_QMiso_fortran_envECreal32 = external constant i32
  @_QMiso_fortran_envECreal64 = external constant i32
  @_QMf90_kindECreal64x2 = external constant i32
  @_QMf90_kindECsingle = external constant i32
  @_QMf90_kindECtwobyte = external constant i32
  @_QMf90_kindECucs2 = external constant i32
  @_QMf90_kindECucs4 = external constant i32
  @_QMf90_kindECword = external constant i32
  @_QQcl.2E2F627567312E66393000 = linkonce constant [11 x i8] c"./bug1.f90\00"
  @_QQcl.2831362C313629 = linkonce constant [7 x i8] c"(16,16)"
  @_QQcl.28346631302E3329 = linkonce constant [8 x i8] c"(4f10.3)"
  
  declare ptr @malloc(i64)
  
  declare void @free(ptr)
  
  define void @_QQmain() !dbg !3 {
    %1 = alloca { ptr, i64, i32, i8, i8, i8, i8 }, align 8, !dbg !7
    %2 = alloca half, i64 1, align 2, !dbg !9
    %3 = call ptr @_FortranAioBeginExternalListOutput(i32 -1, ptr @_QQcl.2E2F627567312E66393000, i32 9), !dbg !10
    %4 = call i1 @_FortranAioOutputAscii(ptr %3, ptr @_QQcl.2831362C313629, i64 7), !dbg !11
    %5 = call i32 @_FortranAioEndIoStatement(ptr %3), !dbg !12
    %6 = call ptr @_FortranAioBeginExternalFormattedOutput(ptr @_QQcl.28346631302E3329, i64 8, i32 -1, ptr @_QQcl.2E2F627567312E66393000, i32 10), !dbg !13
    %7 = load half, ptr @_QMhp237Ea11, align 2, !dbg !14
    %8 = load half, ptr @_QMhp237Eb1a, align 2, !dbg !15
    %9 = fpext half %7 to float, !dbg !16
    %10 = fpext half %8 to float, !dbg !17
    %11 = call float @llvm.copysign.f32(float %9, float %10), !dbg !18
    %12 = fptrunc float %11 to half, !dbg !19
    store half %12, ptr %2, align 2, !dbg !20
    %13 = insertvalue { ptr, i64, i32, i8, i8, i8, i8 } { ptr undef, i64 2, i32 20180515, i8 0, i8 25, i8 0, i8 0 }, ptr %2, 0, !dbg !7
    store { ptr, i64, i32, i8, i8, i8, i8 } %13, ptr %1, align 8, !dbg !7
    %14 = call i1 @_FortranAioOutputDescriptor(ptr %6, ptr %1), !dbg !21
    %15 = call i32 @_FortranAioEndIoStatement(ptr %6), !dbg !22
    ret void, !dbg !23
  }
  
  declare ptr @_FortranAioBeginExternalListOutput(i32, ptr, i32)
  
  declare i1 @_FortranAioOutputAscii(ptr, ptr, i64)
  
  declare i32 @_FortranAioEndIoStatement(ptr)
  
  declare ptr @_FortranAioBeginExternalFormattedOutput(ptr, i64, i32, ptr, i32)
  
  declare i1 @_FortranAioOutputDescriptor(ptr, ptr)
  
  ; Function Attrs: nocallback nofree nosync nounwind readnone speculatable willreturn
  declare float @llvm.copysign.f32(float, float) #0
  
  attributes #0 = { nocallback nofree nosync nounwind readnone speculatable willreturn }
  
  !llvm.dbg.cu = !{!0}
  !llvm.module.flags = !{!2}
  
  !0 = distinct !DICompileUnit(language: DW_LANG_C, file: !1, producer: "mlir", isOptimized: true, runtimeVersion: 0, emissionKind: FullDebug)
  !1 = !DIFile(filename: "FIRModule", directory: "/")
  !2 = !{i32 2, !"Debug Info Version", i32 3}
  !3 = distinct !DISubprogram(name: "_QQmain", linkageName: "_QQmain", scope: null, file: !4, line: 9, type: !5, scopeLine: 9, spFlags: DISPFlagDefinition | DISPFlagOptimized, unit: !0, retainedNodes: !6)
  !4 = !DIFile(filename: "<stdin>", directory: "/local/home/vclement/llvm-project/build")
  !5 = !DISubroutineType(types: !6)
  !6 = !{}
  !7 = !DILocation(line: 39, column: 9, scope: !8)
  !8 = !DILexicalBlockFile(scope: !3, file: !4, discriminator: 0)
  !9 = !DILocation(line: 10, column: 8, scope: !8)
  !10 = !DILocation(line: 17, column: 8, scope: !8)
  !11 = !DILocation(line: 22, column: 8, scope: !8)
  !12 = !DILocation(line: 23, column: 9, scope: !8)
  !13 = !DILocation(line: 31, column: 9, scope: !8)
  !14 = !DILocation(line: 32, column: 9, scope: !8)
  !15 = !DILocation(line: 33, column: 9, scope: !8)
  !16 = !DILocation(line: 34, column: 9, scope: !8)
  !17 = !DILocation(line: 35, column: 9, scope: !8)
  !18 = !DILocation(line: 36, column: 9, scope: !8)
  !19 = !DILocation(line: 37, column: 9, scope: !8)
  !20 = !DILocation(line: 38, column: 3, scope: !8)
  !21 = !DILocation(line: 41, column: 9, scope: !8)
  !22 = !DILocation(line: 42, column: 9, scope: !8)
  !23 = !DILocation(line: 43, column: 3, scope: !8)


Repository:
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CHANGES SINCE LAST ACTION
  https://reviews.llvm.org/D107082/new/

https://reviews.llvm.org/D107082