Second try at making direct object emission produce the same results
as llc + llvm-mc. This time ELF is not changed and I tested that llvm-gcc
bootstrap on darwin10 using darwin9's assembler and linker.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@121006 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/MC/MCAsmInfoDarwin.cpp b/lib/MC/MCAsmInfoDarwin.cpp
index 1147f02..a382741 100644
--- a/lib/MC/MCAsmInfoDarwin.cpp
+++ b/lib/MC/MCAsmInfoDarwin.cpp
@@ -40,7 +40,8 @@
// FIXME: Darwin 10 and newer don't need this.
LinkerRequiresNonEmptyDwarfLines = true;
-
+
+ NeedsSetToChangeDiffSize = true;
HiddenVisibilityAttr = MCSA_PrivateExtern;
// Doesn't support protected visibility.
ProtectedVisibilityAttr = MCSA_Global;
diff --git a/lib/MC/MCAsmStreamer.cpp b/lib/MC/MCAsmStreamer.cpp
index ab807ed..ce85e46 100644
--- a/lib/MC/MCAsmStreamer.cpp
+++ b/lib/MC/MCAsmStreamer.cpp
@@ -512,32 +512,6 @@
EmitValue(MCConstantExpr::Create(Value, getContext()), Size, AddrSpace);
}
-static bool hasSymbolDifference(const MCExpr *Value) {
- switch (Value->getKind()) {
- case MCExpr::Target: llvm_unreachable("Can't handle target exprs yet!");
- case MCExpr::Constant:
- case MCExpr::SymbolRef:
- return false;
- case MCExpr::Unary:
- return hasSymbolDifference(cast<MCUnaryExpr>(Value)->getSubExpr());
- case MCExpr::Binary: {
- const MCBinaryExpr *BE = cast<MCBinaryExpr>(Value);
- if (BE->getOpcode() == MCBinaryExpr::Sub &&
- BE->getLHS()->getKind() == MCExpr::SymbolRef &&
- BE->getRHS()->getKind() == MCExpr::SymbolRef)
- return true;
- return hasSymbolDifference(BE->getLHS()) ||
- hasSymbolDifference(BE->getRHS());
- }
- }
- llvm_unreachable("Switch covers all cases");
-}
-
-bool MCAsmStreamer::needsSet(const MCExpr *Value) {
- return getContext().getAsmInfo().needsSetToChangeDiffSize() &&
- hasSymbolDifference(Value);
-}
-
void MCAsmStreamer::EmitValue(const MCExpr *Value, unsigned Size,
unsigned AddrSpace) {
assert(CurSection && "Cannot emit contents before setting section!");
@@ -565,14 +539,6 @@
}
assert(Directive && "Invalid size for machine code value!");
- if (needsSet(Value)) {
- MCSymbol *SetLabel = getContext().CreateTempSymbol();
- EmitAssignment(SetLabel, Value);
- OS << Directive << *SetLabel;
- EmitEOL();
- return;
- }
-
OS << Directive << *Value;
EmitEOL();
}
diff --git a/lib/MC/MCDwarf.cpp b/lib/MC/MCDwarf.cpp
index 53731dc..3e10f95 100644
--- a/lib/MC/MCDwarf.cpp
+++ b/lib/MC/MCDwarf.cpp
@@ -213,15 +213,8 @@
// The first 4 bytes is the total length of the information for this
// compilation unit (not including these 4 bytes for the length).
- // FIXME: We create the dummy TotalLength variable because LineEndSym points
- // to the end of the section and the darwin assembler doesn't consider that
- // difference an assembly time constant. It might be better for this to be
- // proected by a flag.
- MCSymbol *TotalLength = MCOS->getContext().CreateTempSymbol();
- MCOS->EmitAssignment(TotalLength,
- MakeStartMinusEndExpr(MCOS, LineStartSym, LineEndSym,
- 4));
- MCOS->EmitSymbolValue(TotalLength, 4, 0);
+ MCOS->EmitAbsValue(MakeStartMinusEndExpr(MCOS, LineStartSym, LineEndSym,4),
+ 4);
// Next 2 bytes is the Version, which is Dwarf 2.
MCOS->EmitIntValue(2, 2);
@@ -233,7 +226,7 @@
// section to the end of the prologue. Not including the 4 bytes for the
// total length, the 2 bytes for the version, and these 4 bytes for the
// length of the prologue.
- MCOS->EmitValue(MakeStartMinusEndExpr(MCOS, LineStartSym, ProEndSym,
+ MCOS->EmitAbsValue(MakeStartMinusEndExpr(MCOS, LineStartSym, ProEndSym,
(4 + 2 + 4)),
4, 0);
diff --git a/lib/MC/MCStreamer.cpp b/lib/MC/MCStreamer.cpp
index 6df4ae4..096cea7 100644
--- a/lib/MC/MCStreamer.cpp
+++ b/lib/MC/MCStreamer.cpp
@@ -7,6 +7,7 @@
//
//===----------------------------------------------------------------------===//
+#include "llvm/MC/MCAsmInfo.h"
#include "llvm/MC/MCContext.h"
#include "llvm/MC/MCStreamer.h"
#include "llvm/MC/MCExpr.h"
@@ -72,6 +73,17 @@
EmitBytes(OSE.str(), AddrSpace);
}
+void MCStreamer::EmitAbsValue(const MCExpr *Value, unsigned Size,
+ unsigned AddrSpace) {
+ if (!getContext().getAsmInfo().needsSetToChangeDiffSize()) {
+ EmitValue(Value, Size, AddrSpace);
+ return;
+ }
+ MCSymbol *ABS = getContext().CreateTempSymbol();
+ EmitAssignment(ABS, Value);
+ EmitSymbolValue(ABS, Size, AddrSpace);
+}
+
void MCStreamer::EmitSymbolValue(const MCSymbol *Sym, unsigned Size,
unsigned AddrSpace) {
EmitValue(MCSymbolRefExpr::Create(Sym, getContext()), Size, AddrSpace);