diff --git a/llvm/include/llvm/ExecutionEngine/JITLink/JITLink.h b/llvm/include/llvm/ExecutionEngine/JITLink/JITLink.h
--- a/llvm/include/llvm/ExecutionEngine/JITLink/JITLink.h
+++ b/llvm/include/llvm/ExecutionEngine/JITLink/JITLink.h
@@ -1051,8 +1051,8 @@
/// added to the cache manually (descending offset order must be
/// preserved), or the cache can be set to None and rebuilt by
/// splitBlock on the next call.
- Block &splitBlock(Block &B, size_t SplitIndex,
- SplitBlockCache *Cache = nullptr);
+ Expected<Block &> splitBlock(Block &B, size_t SplitIndex,
+ SplitBlockCache *Cache = nullptr);
/// Add an external symbol.
/// Some formats (e.g. ELF) allow Symbols to have sizes. For Symbols whose
diff --git a/llvm/lib/ExecutionEngine/JITLink/EHFrameSupport.cpp b/llvm/lib/ExecutionEngine/JITLink/EHFrameSupport.cpp
--- a/llvm/lib/ExecutionEngine/JITLink/EHFrameSupport.cpp
+++ b/llvm/lib/ExecutionEngine/JITLink/EHFrameSupport.cpp
@@ -113,9 +113,10 @@
}
uint64_t BlockSize = BlockReader.getOffset() - RecordStartOffset;
- auto &NewBlock = G.splitBlock(B, BlockSize);
- (void)NewBlock;
- LLVM_DEBUG(dbgs() << " Extracted " << NewBlock << "\n");
+ auto NewBlock = G.splitBlock(B, BlockSize);
+ if (!NewBlock)
+ return NewBlock.takeError();
+ LLVM_DEBUG(dbgs() << " Extracted " << *NewBlock << "\n");
}
}
diff --git a/llvm/lib/ExecutionEngine/JITLink/JITLink.cpp b/llvm/lib/ExecutionEngine/JITLink/JITLink.cpp
--- a/llvm/lib/ExecutionEngine/JITLink/JITLink.cpp
+++ b/llvm/lib/ExecutionEngine/JITLink/JITLink.cpp
@@ -150,8 +150,8 @@
B->~Block();
}
-Block &LinkGraph::splitBlock(Block &B, size_t SplitIndex,
- SplitBlockCache *Cache) {
+Expected<Block &> LinkGraph::splitBlock(Block &B, size_t SplitIndex,
+ SplitBlockCache *Cache) {
assert(SplitIndex > 0 && "splitBlock can not be called with SplitIndex == 0");
@@ -213,7 +213,12 @@
// Transfer all symbols with offset less than SplitIndex to NewBlock.
while (!BlockSymbols.empty() &&
BlockSymbols.back()->getOffset() < SplitIndex) {
- BlockSymbols.back()->setBlock(NewBlock);
+ auto *Sym = BlockSymbols.back();
+ // If there are symbols span across the split boundary, return error.
+ if (Sym->getOffset() + Sym->getSize() > SplitIndex)
+ return make_error<JITLinkError>(
+ "symbol span across the split boundary");
+ Sym->setBlock(NewBlock);
BlockSymbols.pop_back();
}
diff --git a/llvm/lib/ExecutionEngine/JITLink/MachOLinkGraphBuilder.cpp b/llvm/lib/ExecutionEngine/JITLink/MachOLinkGraphBuilder.cpp
--- a/llvm/lib/ExecutionEngine/JITLink/MachOLinkGraphBuilder.cpp
+++ b/llvm/lib/ExecutionEngine/JITLink/MachOLinkGraphBuilder.cpp
@@ -317,7 +317,9 @@
Data ? G->createContentBlock(GraphSec, ArrayRef<char>(Data, Size),
Address, Alignment, 0)
: G->createZeroFillBlock(GraphSec, Size, Address, Alignment, 0);
- auto &Sym = G->addAnonymousSymbol(B, 0, Size, false, IsLive);
+ // Create section start symbol with size 0 so the start symbol will not block
+ // splitBlock if needs to be performed.
+ auto &Sym = G->addAnonymousSymbol(B, 0, 0, false, IsLive);
auto SecI = IndexToSection.find(SecIndex);
assert(SecI != IndexToSection.end() && "SecIndex invalid");
auto &NSec = SecI->second;
@@ -764,14 +766,16 @@
LinkGraph::SplitBlockCache C;
for (unsigned I = 0; I != NumBlocks; ++I) {
- auto &CURec = G.splitBlock(*B, CURecordSize, &C);
+ auto CURec = G.splitBlock(*B, CURecordSize, &C);
+ if (!CURec)
+ return CURec.takeError();
bool AddedKeepAlive = false;
- for (auto &E : CURec.edges()) {
+ for (auto &E : CURec->edges()) {
if (E.getOffset() == 0) {
LLVM_DEBUG({
dbgs() << " Updating compact unwind record at "
- << formatv("{0:x16}", CURec.getAddress()) << " to point to "
+ << formatv("{0:x16}", CURec->getAddress()) << " to point to "
<< (E.getTarget().hasName() ? E.getTarget().getName()
: StringRef())
<< " (at " << formatv("{0:x16}", E.getTarget().getAddress())
@@ -781,25 +785,25 @@
if (E.getTarget().isExternal())
return make_error<JITLinkError>(
"Error adding keep-alive edge for compact unwind record at " +
- formatv("{0:x}", CURec.getAddress()) + ": target " +
+ formatv("{0:x}", CURec->getAddress()) + ": target " +
E.getTarget().getName() + " is an external symbol");
auto &TgtBlock = E.getTarget().getBlock();
auto &CURecSym =
- G.addAnonymousSymbol(CURec, 0, CURecordSize, 0, false);
+ G.addAnonymousSymbol(*CURec, 0, CURecordSize, 0, false);
TgtBlock.addEdge(Edge::KeepAlive, 0, CURecSym, 0);
AddedKeepAlive = true;
} else if (E.getOffset() != PersonalityEdgeOffset &&
E.getOffset() != LSDAEdgeOffset)
- return make_error<JITLinkError>("Unexpected edge at offset " +
- formatv("{0:x}", E.getOffset()) +
- " in compact unwind record at " +
- formatv("{0:x}", CURec.getAddress()));
+ return make_error<JITLinkError>(
+ "Unexpected edge at offset " + formatv("{0:x}", E.getOffset()) +
+ " in compact unwind record at " +
+ formatv("{0:x}", CURec->getAddress()));
}
if (!AddedKeepAlive)
return make_error<JITLinkError>(
"Error adding keep-alive edge for compact unwind record at " +
- formatv("{0:x}", CURec.getAddress()) +
+ formatv("{0:x}", CURec->getAddress()) +
": no outgoing target edge at offset 0");
}
}
diff --git a/llvm/unittests/ExecutionEngine/JITLink/LinkGraphTests.cpp b/llvm/unittests/ExecutionEngine/JITLink/LinkGraphTests.cpp
--- a/llvm/unittests/ExecutionEngine/JITLink/LinkGraphTests.cpp
+++ b/llvm/unittests/ExecutionEngine/JITLink/LinkGraphTests.cpp
@@ -10,6 +10,7 @@
#include "llvm/ExecutionEngine/JITLink/JITLink.h"
#include "llvm/Support/Endian.h"
#include "llvm/Support/Memory.h"
+#include "llvm/Testing/Support/Error.h"
#include "gtest/gtest.h"
using namespace llvm;
@@ -513,23 +514,24 @@
B1.addEdge(Edge::FirstRelocation, 12, ES4, 0);
// Split B1.
- auto &B2 = G.splitBlock(B1, 8);
+ auto B2 = G.splitBlock(B1, 8);
+ EXPECT_THAT_EXPECTED(B2, Succeeded());
// Check that the block addresses and content matches what we would expect.
EXPECT_EQ(B1.getAddress(), 0x1008U);
EXPECT_EQ(B1.getContent(), BlockContent.slice(8));
- EXPECT_EQ(B2.getAddress(), 0x1000U);
- EXPECT_EQ(B2.getContent(), BlockContent.slice(0, 8));
+ EXPECT_EQ(B2->getAddress(), 0x1000U);
+ EXPECT_EQ(B2->getContent(), BlockContent.slice(0, 8));
// Check that symbols in B1 were transferred as expected:
// We expect S1 and S2 to have been transferred to B2, and S3 and S4 to have
// remained attached to B1. Symbols S3 and S4 should have had their offsets
// slid to account for the change in address of B2.
- EXPECT_EQ(&S1.getBlock(), &B2);
+ EXPECT_EQ(&S1.getBlock(), &B2.get());
EXPECT_EQ(S1.getOffset(), 0U);
- EXPECT_EQ(&S2.getBlock(), &B2);
+ EXPECT_EQ(&S2.getBlock(), &B2.get());
EXPECT_EQ(S2.getOffset(), 4U);
EXPECT_EQ(&S3.getBlock(), &B1);
@@ -550,13 +552,28 @@
EXPECT_EQ(E2->getOffset(), 4U);
}
- EXPECT_EQ(llvm::size(B2.edges()), 2);
- if (size(B2.edges()) == 2) {
- auto *E1 = &*B2.edges().begin();
- auto *E2 = &*(B2.edges().begin() + 1);
+ EXPECT_EQ(llvm::size(B2->edges()), 2);
+ if (size(B2->edges()) == 2) {
+ auto *E1 = &*B2->edges().begin();
+ auto *E2 = &*(B2->edges().begin() + 1);
if (E2->getOffset() < E1->getOffset())
std::swap(E1, E2);
EXPECT_EQ(E1->getOffset(), 0U);
EXPECT_EQ(E2->getOffset(), 4U);
}
}
+
+TEST(LinkGraphTest, SplitBlockError) {
+ LinkGraph G("foo", Triple("x86_64-apple-darwin"), 8, support::little,
+ getGenericEdgeKindName);
+ auto &Sec = G.createSection("__data", MemProt::Read | MemProt::Write);
+
+ // Create the block to split.
+ auto &B1 = G.createContentBlock(Sec, BlockContent, 0x1000, 8, 0);
+
+ // Add anonymous symbol to the block that mark the entire block.
+ G.addDefinedSymbol(B1, 0, "Sym", BlockContent.size(), Linkage::Strong,
+ Scope::Default, false, false);
+ auto B2 = G.splitBlock(B1, 8);
+ EXPECT_THAT_EXPECTED(B2, Failed());
+}