Re-apply r286006: Fix 24560: assembler does not share constant pool for same constants
Re-applying now that the open bug on this commit, PR32825, is known to be fixed.
Original commit message:
Summary: This patch returns the same label if the CP entry with the same value has been created.
Reviewers: eli.friedman, rengolin, jmolloy
Subscribers: majnemer, jmolloy, llvm-commits
Differential Revision: https://reviews.llvm.org/D25804
llvm-svn: 303539
diff --git a/llvm/lib/MC/ConstantPools.cpp b/llvm/lib/MC/ConstantPools.cpp
index 1763d09..8c94e27 100644
--- a/llvm/lib/MC/ConstantPools.cpp
+++ b/llvm/lib/MC/ConstantPools.cpp
@@ -39,10 +39,20 @@
const MCExpr *ConstantPool::addEntry(const MCExpr *Value, MCContext &Context,
unsigned Size, SMLoc Loc) {
+ const MCConstantExpr *C = dyn_cast<MCConstantExpr>(Value);
+
+ // Check if there is existing entry for the same constant. If so, reuse it.
+ auto Itr = C ? CachedEntries.find(C->getValue()) : CachedEntries.end();
+ if (Itr != CachedEntries.end())
+ return Itr->second;
+
MCSymbol *CPEntryLabel = Context.createTempSymbol();
Entries.push_back(ConstantPoolEntry(CPEntryLabel, Value, Size, Loc));
- return MCSymbolRefExpr::create(CPEntryLabel, Context);
+ const auto SymRef = MCSymbolRefExpr::create(CPEntryLabel, Context);
+ if (C)
+ CachedEntries[C->getValue()] = SymRef;
+ return SymRef;
}
bool ConstantPool::empty() { return Entries.empty(); }