llvm-mirror/lib/IR/DiagnosticInfo.cpp
Duncan P. N. Exon Smith 3d57886267 IR: Split Metadata from Value
Split `Metadata` away from the `Value` class hierarchy, as part of
PR21532.  Assembly and bitcode changes are in the wings, but this is the
bulk of the change for the IR C++ API.

I have a follow-up patch prepared for `clang`.  If this breaks other
sub-projects, I apologize in advance :(.  Help me compile it on Darwin
I'll try to fix it.  FWIW, the errors should be easy to fix, so it may
be simpler to just fix it yourself.

This breaks the build for all metadata-related code that's out-of-tree.
Rest assured the transition is mechanical and the compiler should catch
almost all of the problems.

Here's a quick guide for updating your code:

  - `Metadata` is the root of a class hierarchy with three main classes:
    `MDNode`, `MDString`, and `ValueAsMetadata`.  It is distinct from
    the `Value` class hierarchy.  It is typeless -- i.e., instances do
    *not* have a `Type`.

  - `MDNode`'s operands are all `Metadata *` (instead of `Value *`).

  - `TrackingVH<MDNode>` and `WeakVH` referring to metadata can be
    replaced with `TrackingMDNodeRef` and `TrackingMDRef`, respectively.

    If you're referring solely to resolved `MDNode`s -- post graph
    construction -- just use `MDNode*`.

  - `MDNode` (and the rest of `Metadata`) have only limited support for
    `replaceAllUsesWith()`.

    As long as an `MDNode` is pointing at a forward declaration -- the
    result of `MDNode::getTemporary()` -- it maintains a side map of its
    uses and can RAUW itself.  Once the forward declarations are fully
    resolved RAUW support is dropped on the ground.  This means that
    uniquing collisions on changing operands cause nodes to become
    "distinct".  (This already happened fairly commonly, whenever an
    operand went to null.)

    If you're constructing complex (non self-reference) `MDNode` cycles,
    you need to call `MDNode::resolveCycles()` on each node (or on a
    top-level node that somehow references all of the nodes).  Also,
    don't do that.  Metadata cycles (and the RAUW machinery needed to
    construct them) are expensive.

  - An `MDNode` can only refer to a `Constant` through a bridge called
    `ConstantAsMetadata` (one of the subclasses of `ValueAsMetadata`).

    As a side effect, accessing an operand of an `MDNode` that is known
    to be, e.g., `ConstantInt`, takes three steps: first, cast from
    `Metadata` to `ConstantAsMetadata`; second, extract the `Constant`;
    third, cast down to `ConstantInt`.

    The eventual goal is to introduce `MDInt`/`MDFloat`/etc. and have
    metadata schema owners transition away from using `Constant`s when
    the type isn't important (and they don't care about referring to
    `GlobalValue`s).

    In the meantime, I've added transitional API to the `mdconst`
    namespace that matches semantics with the old code, in order to
    avoid adding the error-prone three-step equivalent to every call
    site.  If your old code was:

        MDNode *N = foo();
        bar(isa             <ConstantInt>(N->getOperand(0)));
        baz(cast            <ConstantInt>(N->getOperand(1)));
        bak(cast_or_null    <ConstantInt>(N->getOperand(2)));
        bat(dyn_cast        <ConstantInt>(N->getOperand(3)));
        bay(dyn_cast_or_null<ConstantInt>(N->getOperand(4)));

    you can trivially match its semantics with:

        MDNode *N = foo();
        bar(mdconst::hasa               <ConstantInt>(N->getOperand(0)));
        baz(mdconst::extract            <ConstantInt>(N->getOperand(1)));
        bak(mdconst::extract_or_null    <ConstantInt>(N->getOperand(2)));
        bat(mdconst::dyn_extract        <ConstantInt>(N->getOperand(3)));
        bay(mdconst::dyn_extract_or_null<ConstantInt>(N->getOperand(4)));

    and when you transition your metadata schema to `MDInt`:

        MDNode *N = foo();
        bar(isa             <MDInt>(N->getOperand(0)));
        baz(cast            <MDInt>(N->getOperand(1)));
        bak(cast_or_null    <MDInt>(N->getOperand(2)));
        bat(dyn_cast        <MDInt>(N->getOperand(3)));
        bay(dyn_cast_or_null<MDInt>(N->getOperand(4)));

  - A `CallInst` -- specifically, intrinsic instructions -- can refer to
    metadata through a bridge called `MetadataAsValue`.  This is a
    subclass of `Value` where `getType()->isMetadataTy()`.

    `MetadataAsValue` is the *only* class that can legally refer to a
    `LocalAsMetadata`, which is a bridged form of non-`Constant` values
    like `Argument` and `Instruction`.  It can also refer to any other
    `Metadata` subclass.

(I'll break all your testcases in a follow-up commit, when I propagate
this change to assembly.)

llvm-svn: 223802
2014-12-09 18:38:53 +00:00

210 lines
7.8 KiB
C++

//===- llvm/Support/DiagnosticInfo.cpp - Diagnostic Definitions -*- C++ -*-===//
//
// The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
// This file defines the different classes involved in low level diagnostics.
//
// Diagnostics reporting is still done as part of the LLVMContext.
//===----------------------------------------------------------------------===//
#include "LLVMContextImpl.h"
#include "llvm/ADT/Twine.h"
#include "llvm/IR/Constants.h"
#include "llvm/IR/DebugInfo.h"
#include "llvm/IR/DiagnosticInfo.h"
#include "llvm/IR/DiagnosticPrinter.h"
#include "llvm/IR/Function.h"
#include "llvm/IR/Instruction.h"
#include "llvm/IR/Metadata.h"
#include "llvm/IR/Module.h"
#include "llvm/Support/Atomic.h"
#include "llvm/Support/CommandLine.h"
#include "llvm/Support/Regex.h"
#include <string>
using namespace llvm;
namespace {
/// \brief Regular expression corresponding to the value given in one of the
/// -pass-remarks* command line flags. Passes whose name matches this regexp
/// will emit a diagnostic when calling the associated diagnostic function
/// (emitOptimizationRemark, emitOptimizationRemarkMissed or
/// emitOptimizationRemarkAnalysis).
struct PassRemarksOpt {
std::shared_ptr<Regex> Pattern;
void operator=(const std::string &Val) {
// Create a regexp object to match pass names for emitOptimizationRemark.
if (!Val.empty()) {
Pattern = std::make_shared<Regex>(Val);
std::string RegexError;
if (!Pattern->isValid(RegexError))
report_fatal_error("Invalid regular expression '" + Val +
"' in -pass-remarks: " + RegexError,
false);
}
};
};
static PassRemarksOpt PassRemarksOptLoc;
static PassRemarksOpt PassRemarksMissedOptLoc;
static PassRemarksOpt PassRemarksAnalysisOptLoc;
// -pass-remarks
// Command line flag to enable emitOptimizationRemark()
static cl::opt<PassRemarksOpt, true, cl::parser<std::string>>
PassRemarks("pass-remarks", cl::value_desc("pattern"),
cl::desc("Enable optimization remarks from passes whose name match "
"the given regular expression"),
cl::Hidden, cl::location(PassRemarksOptLoc), cl::ValueRequired,
cl::ZeroOrMore);
// -pass-remarks-missed
// Command line flag to enable emitOptimizationRemarkMissed()
static cl::opt<PassRemarksOpt, true, cl::parser<std::string>> PassRemarksMissed(
"pass-remarks-missed", cl::value_desc("pattern"),
cl::desc("Enable missed optimization remarks from passes whose name match "
"the given regular expression"),
cl::Hidden, cl::location(PassRemarksMissedOptLoc), cl::ValueRequired,
cl::ZeroOrMore);
// -pass-remarks-analysis
// Command line flag to enable emitOptimizationRemarkAnalysis()
static cl::opt<PassRemarksOpt, true, cl::parser<std::string>>
PassRemarksAnalysis(
"pass-remarks-analysis", cl::value_desc("pattern"),
cl::desc(
"Enable optimization analysis remarks from passes whose name match "
"the given regular expression"),
cl::Hidden, cl::location(PassRemarksAnalysisOptLoc), cl::ValueRequired,
cl::ZeroOrMore);
}
int llvm::getNextAvailablePluginDiagnosticKind() {
static sys::cas_flag PluginKindID = DK_FirstPluginKind;
return (int)sys::AtomicIncrement(&PluginKindID);
}
DiagnosticInfoInlineAsm::DiagnosticInfoInlineAsm(const Instruction &I,
const Twine &MsgStr,
DiagnosticSeverity Severity)
: DiagnosticInfo(DK_InlineAsm, Severity), LocCookie(0), MsgStr(MsgStr),
Instr(&I) {
if (const MDNode *SrcLoc = I.getMetadata("srcloc")) {
if (SrcLoc->getNumOperands() != 0)
if (const auto *CI =
mdconst::dyn_extract<ConstantInt>(SrcLoc->getOperand(0)))
LocCookie = CI->getZExtValue();
}
}
void DiagnosticInfoInlineAsm::print(DiagnosticPrinter &DP) const {
DP << getMsgStr();
if (getLocCookie())
DP << " at line " << getLocCookie();
}
void DiagnosticInfoStackSize::print(DiagnosticPrinter &DP) const {
DP << "stack size limit exceeded (" << getStackSize() << ") in "
<< getFunction();
}
void DiagnosticInfoDebugMetadataVersion::print(DiagnosticPrinter &DP) const {
DP << "ignoring debug info with an invalid version (" << getMetadataVersion()
<< ") in " << getModule();
}
void DiagnosticInfoSampleProfile::print(DiagnosticPrinter &DP) const {
if (getFileName() && getLineNum() > 0)
DP << getFileName() << ":" << getLineNum() << ": ";
else if (getFileName())
DP << getFileName() << ": ";
DP << getMsg();
}
bool DiagnosticInfoOptimizationBase::isLocationAvailable() const {
return getDebugLoc().isUnknown() == false;
}
void DiagnosticInfoOptimizationBase::getLocation(StringRef *Filename,
unsigned *Line,
unsigned *Column) const {
DILocation DIL(getDebugLoc().getAsMDNode(getFunction().getContext()));
*Filename = DIL.getFilename();
*Line = DIL.getLineNumber();
*Column = DIL.getColumnNumber();
}
const std::string DiagnosticInfoOptimizationBase::getLocationStr() const {
StringRef Filename("<unknown>");
unsigned Line = 0;
unsigned Column = 0;
if (isLocationAvailable())
getLocation(&Filename, &Line, &Column);
return Twine(Filename + ":" + Twine(Line) + ":" + Twine(Column)).str();
}
void DiagnosticInfoOptimizationBase::print(DiagnosticPrinter &DP) const {
DP << getLocationStr() << ": " << getMsg();
}
bool DiagnosticInfoOptimizationRemark::isEnabled() const {
return PassRemarksOptLoc.Pattern &&
PassRemarksOptLoc.Pattern->match(getPassName());
}
bool DiagnosticInfoOptimizationRemarkMissed::isEnabled() const {
return PassRemarksMissedOptLoc.Pattern &&
PassRemarksMissedOptLoc.Pattern->match(getPassName());
}
bool DiagnosticInfoOptimizationRemarkAnalysis::isEnabled() const {
return PassRemarksAnalysisOptLoc.Pattern &&
PassRemarksAnalysisOptLoc.Pattern->match(getPassName());
}
void llvm::emitOptimizationRemark(LLVMContext &Ctx, const char *PassName,
const Function &Fn, const DebugLoc &DLoc,
const Twine &Msg) {
Ctx.diagnose(DiagnosticInfoOptimizationRemark(PassName, Fn, DLoc, Msg));
}
void llvm::emitOptimizationRemarkMissed(LLVMContext &Ctx, const char *PassName,
const Function &Fn,
const DebugLoc &DLoc,
const Twine &Msg) {
Ctx.diagnose(DiagnosticInfoOptimizationRemarkMissed(PassName, Fn, DLoc, Msg));
}
void llvm::emitOptimizationRemarkAnalysis(LLVMContext &Ctx,
const char *PassName,
const Function &Fn,
const DebugLoc &DLoc,
const Twine &Msg) {
Ctx.diagnose(
DiagnosticInfoOptimizationRemarkAnalysis(PassName, Fn, DLoc, Msg));
}
bool DiagnosticInfoOptimizationFailure::isEnabled() const {
// Only print warnings.
return getSeverity() == DS_Warning;
}
void llvm::emitLoopVectorizeWarning(LLVMContext &Ctx, const Function &Fn,
const DebugLoc &DLoc, const Twine &Msg) {
Ctx.diagnose(DiagnosticInfoOptimizationFailure(
Fn, DLoc, Twine("loop not vectorized: " + Msg)));
}
void llvm::emitLoopInterleaveWarning(LLVMContext &Ctx, const Function &Fn,
const DebugLoc &DLoc, const Twine &Msg) {
Ctx.diagnose(DiagnosticInfoOptimizationFailure(
Fn, DLoc, Twine("loop not interleaved: " + Msg)));
}