Unverified Commit 1eab92bd authored by Jay Foad's avatar Jay Foad Committed by GitHub
Browse files

[CodeGen] Implement MVT::getSizeInBits with a lookup table (#65604) 

This allows it to be inlined in Release builds giving a geomean 0.10%
speed up according to https://llvm-compile-time-tracker.com/
parent d6cc3410

llvm/include/llvm/CodeGen/MachineValueType.h

+10 −11
Original line number Diff line number Diff line
@@ -302,18 +302,16 @@ namespace llvm { 
    /// be set and the runtime size will be a positive integer multiple of the

    /// base size.

    TypeSize getSizeInBits() const {

      switch (SimpleTy) {

      default:

        switch (SimpleTy) {

        default:

          llvm_unreachable("getSizeInBits called on extended MVT.");



      static constexpr TypeSize SizeTable[] = {

#define GET_VT_ATTR(Ty, N, Sz, Any, Int, FP, Vec, Sc)                          \

  case Ty:                                                                     \

    return (Sc ? TypeSize::Scalable(Sz) : TypeSize::Fixed(Sz));

  TypeSize(Sz, Sc || Ty == aarch64svcount /* FIXME: Not in the td. */),

#include "llvm/CodeGen/GenVT.inc"

#undef GET_VT_ATTR

        }

      };



      switch (SimpleTy) {

      case INVALID_SIMPLE_VALUE_TYPE:

        llvm_unreachable("getSizeInBits called on extended MVT.");

      case Other:

        llvm_unreachable("Value type is non-standard value, Other.");

      case iPTR:
@@ -329,8 +327,9 @@ namespace llvm { 
                         "in codegen and has no size");

      case Metadata:

        llvm_unreachable("Value type is metadata.");

      case aarch64svcount: // FIXME: Not in the td.

        return TypeSize::Scalable(16);

      default:

        assert(SimpleTy < VALUETYPE_SIZE && "Unexpected value type!");

        return SizeTable[SimpleTy - FIRST_VALUETYPE];

      }

    }