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Revision c3861f5c7371fea2fc5d20404a7f77c927bbd61b authored by Shuhei Kadowaki on 14 August 2021, 12:49:21 UTC, committed by Shuhei Kadowaki on 23 August 2021, 15:09:13 UTC 
`AbstractInterpreter`: generalize `force_const_prop` interface
 
Built on top of #41882, this PR sorts out the constant-prop' interface
yet more, particularly generalizes `force_const_prop` to `const_prop_config`
so that it can turn on and off each heuristic.

The main motivation here is, in #41882, we want to force const-prop' on
`setproperty` even when its return type is already `Const` for the sake
of succeeding inlining, by skipping all the `const_prop_xxx_heuristic` checks.
But I still found we want to apply `const_prop_entry_heuristic` to
`getproperty`, because if we already know very accurate result for a
`getproperty` call, usually there is really no motivation for constant-prop', e.g.:
```julia
struct FZero end
Base.getproperty(::FZero, ::Symbol) = 0.0
getproperty(FZero(), :val) # const-prop' doesn't need to happen here
```

Now `force_const_prop(...) -> force::Bool` is refactored to
`const_prop_config(...) -> config::UInt8`, which can turn on and off
each heuristic based on the value of `config`.

I also included another refactoring that inlines `const_prop_rettype_heuristic`
into `const_prop_argument_heuristic`, because they really seem tightly coupled.
1 parent e1e4986
Raw File
llvmcalltest.cpp 
// This file is a part of Julia. License is MIT: https://julialang.org/license

#include "llvm-version.h"
#include "support/platform.h"
#include "support/dtypes.h"

#include "llvm/Config/llvm-config.h"
#include "llvm/IR/IRBuilder.h"
#include <llvm/Support/raw_ostream.h>

#include "julia.h"
#include "codegen_shared.h"

using namespace llvm;

extern "C" {

JL_DLLEXPORT const char *MakeIdentityFunction(jl_value_t* jl_AnyTy) {
    LLVMContext Ctx;
    PointerType *AnyTy = PointerType::get(StructType::get(Ctx), 0);
    // FIXME: get AnyTy via jl_type_to_llvm(Ctx, jl_AnyTy)

    Type *TrackedTy = PointerType::get(AnyTy->getElementType(), AddressSpace::Tracked);
    Module *M = new llvm::Module("shadow", Ctx);
    Function *F = Function::Create(
        FunctionType::get(
            TrackedTy, {TrackedTy}, false),
        llvm::GlobalValue::ExternalLinkage,
        "identity",
        M
    );

    IRBuilder<> Builder(BasicBlock::Create(Ctx, "top", F));
    Builder.CreateRet(&*F->arg_begin());

    std::string buf;
    raw_string_ostream os(buf);
    M->print(os, NULL);
    os.flush();
    return strdup(buf.c_str());
}

JL_DLLEXPORT const char *MakeLoadGlobalFunction() {
    LLVMContext Ctx;

    auto M = new Module("shadow", Ctx);
    auto intType = Type::getInt32Ty(Ctx);
    auto G = new GlobalVariable(
        *M,
        intType,
        true,
        GlobalValue::InternalLinkage,
        Constant::getNullValue(intType),
        "test_global_var");

    auto resultType = Type::getInt64Ty(Ctx);
    auto F = Function::Create(
        FunctionType::get(resultType, {}, false),
        GlobalValue::ExternalLinkage,
        "load_global_var",
        M);

    IRBuilder<> Builder(BasicBlock::Create(Ctx, "top", F));
    Builder.CreateRet(Builder.CreatePtrToInt(G, resultType));

    std::string buf;
    raw_string_ostream os(buf);
    M->print(os, NULL);
    os.flush();
    return strdup(buf.c_str());
}

}
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