Setting GlobalDirective in TargetAsmInfo by default rather than

providing a misleading facility. It's used once in the MIPS backend
and hardcoded as "\t.globl\t" everywhere else.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@45676 91177308-0d34-0410-b5e6-96231b3b80d8
This commit is contained in:
Gordon Henriksen 2008-01-07 02:31:11 +00:00
parent 9bb0681028
commit 572742e876
5 changed files with 240 additions and 1 deletions

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@ -57,7 +57,12 @@ namespace CallingConv {
/// X86_FastCall - 'fast' analog of X86_StdCall. Passes first two arguments
/// in ECX:EDX registers, others - via stack. Callee is responsible for
/// stack cleaning.
X86_FastCall = 65
X86_FastCall = 65,
/// X86_Ocaml - This is a weird ABI used by Objective Caml. Formally, it
/// supports only one to six integer/address arguments, all in-reg. It also
/// supports tail call emission.
X86_Ocaml = 66
};
} // End CallingConv namespace

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@ -36,6 +36,7 @@ namespace {
(void) llvm::createSimpleRegisterCoalescer();
(void) llvm::createOcamlCollector();
(void) llvm::createShadowStackCollector();
(void) llvm::createBURRListDAGScheduler(NULL, NULL, NULL);

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@ -0,0 +1,177 @@
//===-- OcamlCollector.cpp - Ocaml frametable emitter ---------------------===//
//
// The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
// This file implements lowering for the llvm.gc* intrinsics compatible with
// Objective Caml 3.10.0, which uses a liveness-accurate static stack map.
//
//===----------------------------------------------------------------------===//
#include "llvm/CodeGen/Collectors.h"
#include "llvm/ADT/DenseMap.h"
#include "llvm/CodeGen/AsmPrinter.h"
#include "llvm/CodeGen/Collector.h"
#include "llvm/CodeGen/CollectorMetadata.h"
#include "llvm/Function.h"
#include "llvm/Module.h"
#include "llvm/PassManager.h"
#include "llvm/Support/Compiler.h"
#include "llvm/Target/TargetAsmInfo.h"
#include "llvm/Target/TargetData.h"
#include "llvm/Target/TargetMachine.h"
#include <ctype.h>
using namespace llvm;
namespace {
class VISIBILITY_HIDDEN OcamlCollector : public Collector {
public:
OcamlCollector();
void beginAssembly(std::ostream &OS, AsmPrinter &AP,
const TargetAsmInfo &TAI);
void finishAssembly(std::ostream &OS, AsmPrinter &AP,
const TargetAsmInfo &TAI);
};
CollectorRegistry::Add<OcamlCollector>
X("ocaml", "ocaml 3.10-compatible collector");
}
// -----------------------------------------------------------------------------
static void EmitCamlGlobal(const Module &M, std::ostream &OS, AsmPrinter &AP,
const TargetAsmInfo &TAI, const char *Id) {
const std::string &MId = M.getModuleIdentifier();
std::string Mangled;
Mangled += TAI.getGlobalPrefix();
Mangled += "caml";
size_t Letter = Mangled.size();
Mangled.append(MId.begin(), std::find(MId.begin(), MId.end(), '.'));
Mangled += "__";
Mangled += Id;
// Capitalize the first letter of the module name.
Mangled[Letter] = toupper(Mangled[Letter]);
if (const char *GlobalDirective = TAI.getGlobalDirective())
OS << GlobalDirective << Mangled << "\n";
OS << Mangled << ":\n";
}
Collector *llvm::createOcamlCollector() {
return new OcamlCollector();
}
OcamlCollector::OcamlCollector() {
NeededSafePoints = 1 << GC::PostCall;
}
void OcamlCollector::beginAssembly(std::ostream &OS, AsmPrinter &AP,
const TargetAsmInfo &TAI) {
AP.SwitchToTextSection(TAI.getTextSection());
EmitCamlGlobal(getModule(), OS, AP, TAI, "code_begin");
AP.SwitchToDataSection(TAI.getDataSection());
EmitCamlGlobal(getModule(), OS, AP, TAI, "data_begin");
}
/// emitAssembly - Print the frametable. The ocaml frametable format is thus:
///
/// extern "C" struct align(sizeof(intptr_t)) {
/// uint16_t NumDescriptors;
/// struct align(sizeof(intptr_t)) {
/// void *ReturnAddress;
/// uint16_t FrameSize;
/// uint16_t NumLiveOffsets;
/// uint16_t LiveOffsets[NumLiveOffsets];
/// } Descriptors[NumDescriptors];
/// } caml${module}__frametable;
///
/// Note that this precludes programs from stack frames larger than 64K
/// (FrameSize and LiveOffsets would overflow). FrameTablePrinter will abort if
/// either condition is detected in a function which uses the collector.
///
void OcamlCollector::finishAssembly(std::ostream &OS, AsmPrinter &AP,
const TargetAsmInfo &TAI) {
const char *AddressDirective;
int AddressAlignLog;
if (AP.TM.getTargetData()->getPointerSize() == sizeof(int32_t)) {
AddressDirective = TAI.getData32bitsDirective();
AddressAlignLog = 2;
} else {
AddressDirective = TAI.getData64bitsDirective();
AddressAlignLog = 3;
}
AP.SwitchToTextSection(TAI.getTextSection());
EmitCamlGlobal(getModule(), OS, AP, TAI, "code_end");
AP.SwitchToDataSection(TAI.getDataSection());
EmitCamlGlobal(getModule(), OS, AP, TAI, "data_end");
OS << AddressDirective << 0; // FIXME: Why does ocaml emit this??
AP.EOL();
AP.SwitchToDataSection(TAI.getDataSection());
EmitCamlGlobal(getModule(), OS, AP, TAI, "frametable");
for (iterator FI = begin(), FE = end(); FI != FE; ++FI) {
CollectorMetadata &MD = **FI;
OS << "\t" << TAI.getCommentString() << " live roots for "
<< MD.getFunction().getNameStart() << "\n";
for (CollectorMetadata::iterator PI = MD.begin(),
PE = MD.end(); PI != PE; ++PI) {
uint64_t FrameSize = MD.getFrameSize();
if (FrameSize >= 2<<16) {
cerr << "Function '" << MD.getFunction().getNameStart()
<< "' is too large for the ocaml collector! "
<< "Frame size " << FrameSize << " >= 65536.\n";
abort(); // Very rude!
}
size_t LiveCount = MD.live_size(PI);
if (LiveCount >= 2<<16) {
cerr << "Function '" << MD.getFunction().getNameStart()
<< "' is too large for the ocaml collector! "
<< "Live root count " << LiveCount << " >= 65536.\n";
abort(); // Very rude!
}
OS << AddressDirective
<< TAI.getPrivateGlobalPrefix() << "label" << PI->Num;
AP.EOL("call return address");
AP.EmitInt16(FrameSize);
AP.EOL("stack frame size");
AP.EmitInt16(LiveCount);
AP.EOL("live root count");
for (CollectorMetadata::live_iterator LI = MD.live_begin(PI),
LE = MD.live_end(PI);
LI != LE; ++LI) {
assert(LI->StackOffset < 2<<16 &&
"GC root stack offset is outside of fixed stack frame and out "
"of range for Ocaml collector!");
OS << "\t.word\t" << LI->StackOffset;
AP.EOL("stack offset");
}
AP.EmitAlignment(AddressAlignLog);
}
}
}

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@ -0,0 +1,14 @@
; RUN: llvm-as < %s | llc -asm-verbose | grep {frame size} | grep -v 0x0
declare void @llvm.gcroot(i8** %value, i8* %tag)
declare void @g() gc "ocaml"
define void @f(i8* %arg.0, void()* %arg.1) gc "ocaml" {
entry:
%gcroot.0 = alloca i8*
call void @llvm.gcroot(i8** %gcroot.0, i8* null)
store i8* %arg.0, i8** %gcroot.0
call void @g()
call void %arg.1()
ret void
}

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@ -0,0 +1,42 @@
; RUN: llvm-as < %s | llc | grep caml.*__frametable
; RUN: llvm-as < %s | llc -march=x86 | grep {movl .0}
%struct.obj = type { i8*, %struct.obj* }
define %struct.obj* @fun(%struct.obj* %head) gc "ocaml" {
entry:
%gcroot.0 = alloca i8*
%gcroot.1 = alloca i8*
call void @llvm.gcroot(i8** %gcroot.0, i8* null)
call void @llvm.gcroot(i8** %gcroot.1, i8* null)
%local.0 = bitcast i8** %gcroot.0 to %struct.obj**
%local.1 = bitcast i8** %gcroot.1 to %struct.obj**
store %struct.obj* %head, %struct.obj** %local.0
br label %bb.loop
bb.loop:
%t0 = load %struct.obj** %local.0
%t1 = getelementptr %struct.obj* %t0, i32 0, i32 1
%t2 = bitcast %struct.obj* %t0 to i8*
%t3 = bitcast %struct.obj** %t1 to i8**
%t4 = call i8* @llvm.gcread(i8* %t2, i8** %t3)
%t5 = bitcast i8* %t4 to %struct.obj*
%t6 = icmp eq %struct.obj* %t5, null
br i1 %t6, label %bb.loop, label %bb.end
bb.end:
%t7 = malloc %struct.obj
store %struct.obj* %t7, %struct.obj** %local.1
%t8 = bitcast %struct.obj* %t7 to i8*
%t9 = load %struct.obj** %local.0
%t10 = getelementptr %struct.obj* %t9, i32 0, i32 1
%t11 = bitcast %struct.obj* %t9 to i8*
%t12 = bitcast %struct.obj** %t10 to i8**
call void @llvm.gcwrite(i8* %t8, i8* %t11, i8** %t12)
ret %struct.obj* %t7
}
declare void @llvm.gcroot(i8** %value, i8* %tag)
declare void @llvm.gcwrite(i8* %value, i8* %obj, i8** %field)
declare i8* @llvm.gcread(i8* %obj, i8** %field)