https://github.com/tbaederr updated https://github.com/llvm/llvm-project/pull/69713
>From e11a956d0389b1c0ed4ed54a908c3498dba2aba7 Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?Timm=20B=C3=A4der?= <tbae...@redhat.com> Date: Fri, 20 Oct 2023 14:16:22 +0200 Subject: [PATCH] [clang][Interp] Implement builtin_expect --- clang/lib/AST/Interp/InterpBuiltin.cpp | 52 +++++++++++++++++++ clang/test/AST/Interp/builtin-functions.cpp | 8 +++ .../Sema/builtin-expect-with-probability.cpp | 1 + 3 files changed, 61 insertions(+) diff --git a/clang/lib/AST/Interp/InterpBuiltin.cpp b/clang/lib/AST/Interp/InterpBuiltin.cpp index bb3e13599b01d4e..2cfd19a02c0c33c 100644 --- a/clang/lib/AST/Interp/InterpBuiltin.cpp +++ b/clang/lib/AST/Interp/InterpBuiltin.cpp @@ -33,6 +33,19 @@ PrimType getIntPrimType(const InterpState &S) { llvm_unreachable("Int isn't 16 or 32 bit?"); } +PrimType getLongPrimType(const InterpState &S) { + const TargetInfo &TI = S.getCtx().getTargetInfo(); + unsigned LongWidth = TI.getLongWidth(); + + if (LongWidth == 64) + return PT_Sint64; + else if (LongWidth == 32) + return PT_Sint32; + else if (LongWidth == 16) + return PT_Sint16; + llvm_unreachable("long isn't 16, 32 or 64 bit?"); +} + /// Peek an integer value from the stack into an APSInt. static APSInt peekToAPSInt(InterpStack &Stk, PrimType T, size_t Offset = 0) { if (Offset == 0) @@ -109,6 +122,19 @@ static void pushAPSInt(InterpState &S, const APSInt &Val) { } } +/// Pushes \p Val to the stack, as a target-dependent 'long'. +static void pushLong(InterpState &S, int64_t Val) { + PrimType LongType = getLongPrimType(S); + if (LongType == PT_Sint64) + S.Stk.push<Integral<64, true>>(Integral<64, true>::from(Val)); + else if (LongType == PT_Sint32) + S.Stk.push<Integral<32, true>>(Integral<32, true>::from(Val)); + else if (LongType == PT_Sint16) + S.Stk.push<Integral<16, true>>(Integral<16, true>::from(Val)); + else + llvm_unreachable("Long isn't 16, 32 or 64 bit?"); +} + static void pushSizeT(InterpState &S, uint64_t Val) { const TargetInfo &TI = S.getCtx().getTargetInfo(); unsigned SizeTWidth = TI.getTypeWidth(TI.getSizeType()); @@ -517,6 +543,26 @@ static bool interp__builtin_bitreverse(InterpState &S, CodePtr OpPC, return true; } +// __builtin_expect(long, long) +// __builtin_expect_with_probability(long, long, double) +static bool interp__builtin_expect(InterpState &S, CodePtr OpPC, + const InterpFrame *Frame, + const Function *Func, const CallExpr *Call) { + // The return value is simply the value of the first parameter. + // We ignore the probability. + unsigned NumArgs = Call->getNumArgs(); + assert(NumArgs == 2 || NumArgs == 3); + + PrimType ArgT = *S.getContext().classify(Call->getArg(0)->getType()); + unsigned Offset = align(primSize(getLongPrimType(S))) * 2; + if (NumArgs == 3) + Offset += align(primSize(PT_Float)); + + APSInt Val = peekToAPSInt(S.Stk, ArgT, Offset); + pushLong(S, Val.getSExtValue()); + return true; +} + bool InterpretBuiltin(InterpState &S, CodePtr OpPC, const Function *F, const CallExpr *Call) { InterpFrame *Frame = S.Current; @@ -681,6 +727,12 @@ bool InterpretBuiltin(InterpState &S, CodePtr OpPC, const Function *F, return false; break; + case Builtin::BI__builtin_expect: + case Builtin::BI__builtin_expect_with_probability: + if (!interp__builtin_expect(S, OpPC, Frame, F, Call)) + return false; + break; + default: return false; } diff --git a/clang/test/AST/Interp/builtin-functions.cpp b/clang/test/AST/Interp/builtin-functions.cpp index 0726dab37cb4eb0..35a1f9a75092a05 100644 --- a/clang/test/AST/Interp/builtin-functions.cpp +++ b/clang/test/AST/Interp/builtin-functions.cpp @@ -331,3 +331,11 @@ namespace bitreverse { char bitreverse3[__builtin_bitreverse32(0x12345678) == 0x1E6A2C48 ? 1 : -1]; char bitreverse4[__builtin_bitreverse64(0x0123456789ABCDEFULL) == 0xF7B3D591E6A2C480 ? 1 : -1]; } + +namespace expect { + constexpr int a() { + return 12; + } + static_assert(__builtin_expect(a(),1) == 12, ""); + static_assert(__builtin_expect_with_probability(a(), 1, 1.0) == 12, ""); +} diff --git a/clang/test/Sema/builtin-expect-with-probability.cpp b/clang/test/Sema/builtin-expect-with-probability.cpp index 2b72c7b27ae93e8..c55cde84b254834 100644 --- a/clang/test/Sema/builtin-expect-with-probability.cpp +++ b/clang/test/Sema/builtin-expect-with-probability.cpp @@ -1,4 +1,5 @@ // RUN: %clang_cc1 -fsyntax-only -verify %s +// RUN: %clang_cc1 -fsyntax-only -verify -fexperimental-new-constant-interpreter %s __attribute__((noreturn)) extern void bar(); _______________________________________________ cfe-commits mailing list cfe-commits@lists.llvm.org https://lists.llvm.org/cgi-bin/mailman/listinfo/cfe-commits