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-rw-r--r--include/llvm/CallingConv.h7
-rw-r--r--include/llvm/CodeGen/LinkAllCodegenComponents.h1
-rw-r--r--lib/CodeGen/OcamlCollector.cpp177
-rw-r--r--test/CodeGen/Generic/GC/frame_size.ll14
-rw-r--r--test/CodeGen/Generic/GC/simple_ocaml.ll42
5 files changed, 240 insertions, 1 deletions
diff --git a/include/llvm/CallingConv.h b/include/llvm/CallingConv.h
index bb76def..8b6a01a 100644
--- a/include/llvm/CallingConv.h
+++ b/include/llvm/CallingConv.h
@@ -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
diff --git a/include/llvm/CodeGen/LinkAllCodegenComponents.h b/include/llvm/CodeGen/LinkAllCodegenComponents.h
index 48be541..ac58035 100644
--- a/include/llvm/CodeGen/LinkAllCodegenComponents.h
+++ b/include/llvm/CodeGen/LinkAllCodegenComponents.h
@@ -36,6 +36,7 @@ namespace {
(void) llvm::createSimpleRegisterCoalescer();
+ (void) llvm::createOcamlCollector();
(void) llvm::createShadowStackCollector();
(void) llvm::createBURRListDAGScheduler(NULL, NULL, NULL);
diff --git a/lib/CodeGen/OcamlCollector.cpp b/lib/CodeGen/OcamlCollector.cpp
new file mode 100644
index 0000000..8848fe1
--- /dev/null
+++ b/lib/CodeGen/OcamlCollector.cpp
@@ -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);
+ }
+ }
+}
diff --git a/test/CodeGen/Generic/GC/frame_size.ll b/test/CodeGen/Generic/GC/frame_size.ll
new file mode 100644
index 0000000..75626c1
--- /dev/null
+++ b/test/CodeGen/Generic/GC/frame_size.ll
@@ -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
+}
diff --git a/test/CodeGen/Generic/GC/simple_ocaml.ll b/test/CodeGen/Generic/GC/simple_ocaml.ll
new file mode 100644
index 0000000..a33e035
--- /dev/null
+++ b/test/CodeGen/Generic/GC/simple_ocaml.ll
@@ -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)
generated by cgit v1.1 at 2024-09-16 07:19:41 +0000