[llvm-commits] [llvm] r98924 - in /llvm/trunk: lib/MC/MCAssembler.cpp test/MC/MachO/reloc.s
Daniel Dunbar
daniel at zuster.org
Thu Mar 18 20:18:12 PDT 2010
Author: ddunbar
Date: Thu Mar 18 22:18:12 2010
New Revision: 98924
URL: http://llvm.org/viewvc/llvm-project?rev=98924&view=rev
Log:
MC/Mach-O: Factor out isScatteredFixupFullyResolvedSimple predicate, and fix some corner cases.
Modified:
llvm/trunk/lib/MC/MCAssembler.cpp
llvm/trunk/test/MC/MachO/reloc.s
Modified: llvm/trunk/lib/MC/MCAssembler.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/MC/MCAssembler.cpp?rev=98924&r1=98923&r2=98924&view=diff
==============================================================================
--- llvm/trunk/lib/MC/MCAssembler.cpp (original)
+++ llvm/trunk/lib/MC/MCAssembler.cpp Thu Mar 18 22:18:12 2010
@@ -1010,6 +1010,44 @@
MCAssembler::~MCAssembler() {
}
+static bool isScatteredFixupFullyResolvedSimple(const MCAssembler &Asm,
+ const MCAsmFixup &Fixup,
+ const MCDataFragment *DF,
+ const MCValue Target,
+ const MCSection *BaseSection) {
+ // The effective fixup address is
+ // addr(atom(A)) + offset(A)
+ // - addr(atom(B)) - offset(B)
+ // - addr(<base symbol>) + <fixup offset from base symbol>
+ // and the offsets are not relocatable, so the fixup is fully resolved when
+ // addr(atom(A)) - addr(atom(B)) - addr(<base symbol>)) == 0.
+ //
+ // The simple (Darwin, except on x86_64) way of dealing with this was to
+ // assume that any reference to a temporary symbol *must* be a temporary
+ // symbol in the same atom, unless the sections differ. Therefore, any PCrel
+ // relocation to a temporary symbol (in the same section) is fully
+ // resolved. This also works in conjunction with absolutized .set, which
+ // requires the compiler to use .set to absolutize the differences between
+ // symbols which the compiler knows to be assembly time constants, so we don't
+ // need to worry about consider symbol differences fully resolved.
+
+ // Non-relative fixups are only resolved if constant.
+ if (!BaseSection)
+ return Target.isAbsolute();
+
+ // Otherwise, relative fixups are only resolved if not a difference and the
+ // target is a temporary in the same section.
+ if (Target.isAbsolute() || Target.getSymB())
+ return false;
+
+ const MCSymbol *A = &Target.getSymA()->getSymbol();
+ if (!A->isTemporary() || !A->isInSection() ||
+ &A->getSection() != BaseSection)
+ return false;
+
+ return true;
+}
+
bool MCAssembler::isSymbolLinkerVisible(const MCSymbolData *SD) const {
// Non-temporary labels should always be visible to the linker.
if (!SD->getSymbol().isTemporary())
@@ -1036,34 +1074,33 @@
Value = Target.getConstant();
- // FIXME: This "resolved" check isn't quite right. The assumption is that if
- // we have a PCrel access to a temporary, then that temporary is in the same
- // atom, and so the value is resolved. We need explicit atom's to implement
- // this more precisely.
bool IsResolved = true, IsPCRel = isFixupKindPCRel(Fixup.Kind);
if (const MCSymbolRefExpr *A = Target.getSymA()) {
if (A->getSymbol().isDefined())
Value += getSymbolData(A->getSymbol()).getAddress();
else
IsResolved = false;
-
- // With scattered symbols, we assume anything that isn't a PCrel temporary
- // access can have an arbitrary value.
- if (getBackend().hasScatteredSymbols() &&
- (!IsPCRel || !A->getSymbol().isTemporary()))
- IsResolved = false;
}
if (const MCSymbolRefExpr *B = Target.getSymB()) {
if (B->getSymbol().isDefined())
Value -= getSymbolData(B->getSymbol()).getAddress();
else
IsResolved = false;
+ }
- // With scattered symbols, we assume anything that isn't a PCrel temporary
- // access can have an arbitrary value.
- if (getBackend().hasScatteredSymbols() &&
- (!IsPCRel || !B->getSymbol().isTemporary()))
- IsResolved = false;
+ // If we are using scattered symbols, determine whether this value is actually
+ // resolved; scattering may cause atoms to move.
+ if (IsResolved && getBackend().hasScatteredSymbols()) {
+ if (getBackend().hasReliableSymbolDifference()) {
+ llvm_report_error("FIXME: Not yet implemented");
+ } else {
+ const MCSection *BaseSection = 0;
+ if (IsPCRel)
+ BaseSection = &DF->getParent()->getSection();
+
+ IsResolved = isScatteredFixupFullyResolvedSimple(*this, Fixup, DF, Target,
+ BaseSection);
+ }
}
if (IsPCRel)
Modified: llvm/trunk/test/MC/MachO/reloc.s
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/test/MC/MachO/reloc.s?rev=98924&r1=98923&r2=98924&view=diff
==============================================================================
--- llvm/trunk/test/MC/MachO/reloc.s (original)
+++ llvm/trunk/test/MC/MachO/reloc.s Thu Mar 18 22:18:12 2010
@@ -10,7 +10,7 @@
local_a:
.long 0
-local_a_elt:
+local_a_elt:
.long 0
local_b:
.long local_b - local_c + 245
@@ -27,9 +27,20 @@
.const
.long
-bar:
+bar:
.long local_a_elt - bar + 33
+L0:
+ .long L0
+ .long L1
+
+ .text
+_f0:
+L1:
+ jmp L0
+ jmp L1
+ ret
+
// CHECK: ('cputype', 7)
// CHECK: ('cpusubtype', 3)
// CHECK: ('filetype', 1)
@@ -42,9 +53,9 @@
// CHECK: ('size', 260)
// CHECK: ('segment_name', '\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00')
// CHECK: ('vm_addr', 0)
-// CHECK: ('vm_size', 47)
+// CHECK: ('vm_size', 63)
// CHECK: ('file_offset', 392)
-// CHECK: ('file_size', 47)
+// CHECK: ('file_size', 63)
// CHECK: ('maxprot', 7)
// CHECK: ('initprot', 7)
// CHECK: ('num_sections', 3)
@@ -54,26 +65,29 @@
// CHECK: (('section_name', '__text\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00')
// CHECK: ('segment_name', '__TEXT\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00')
// CHECK: ('address', 0)
-// CHECK: ('size', 0)
+// CHECK: ('size', 8)
// CHECK: ('offset', 392)
// CHECK: ('alignment', 0)
-// CHECK: ('reloc_offset', 0)
-// CHECK: ('num_reloc', 0)
-// CHECK: ('flags', 0x80000000)
+// CHECK: ('reloc_offset', 456)
+// CHECK: ('num_reloc', 1)
+// CHECK: ('flags', 0x80000400)
// CHECK: ('reserved1', 0)
// CHECK: ('reserved2', 0)
// CHECK: ),
// CHECK: ('_relocations', [
+// CHECK: # Relocation 0
+// CHECK: (('word-0', 0x1),
+// CHECK: ('word-1', 0x5000003)),
// CHECK: ])
-// CHECK: ('_section_data', '')
+// CHECK: ('_section_data', '\xe92\x00\x00\x00\xeb\xf9\xc3')
// CHECK: # Section 1
// CHECK: (('section_name', '__data\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00')
// CHECK: ('segment_name', '__DATA\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00')
-// CHECK: ('address', 0)
+// CHECK: ('address', 8)
// CHECK: ('size', 43)
-// CHECK: ('offset', 392)
+// CHECK: ('offset', 400)
// CHECK: ('alignment', 0)
-// CHECK: ('reloc_offset', 440)
+// CHECK: ('reloc_offset', 464)
// CHECK: ('num_reloc', 9)
// CHECK: ('flags', 0x0)
// CHECK: ('reserved1', 0)
@@ -82,72 +96,78 @@
// CHECK: ('_relocations', [
// CHECK: # Relocation 0
// CHECK: (('word-0', 0x8000002a),
-// CHECK: ('word-1', 0x10)),
+// CHECK: ('word-1', 0x18)),
// CHECK: # Relocation 1
// CHECK: (('word-0', 0x90000028),
-// CHECK: ('word-1', 0x10)),
+// CHECK: ('word-1', 0x18)),
// CHECK: # Relocation 2
// CHECK: (('word-0', 0xa0000024),
-// CHECK: ('word-1', 0x10)),
+// CHECK: ('word-1', 0x18)),
// CHECK: # Relocation 3
// CHECK: (('word-0', 0xa0000020),
-// CHECK: ('word-1', 0x10)),
+// CHECK: ('word-1', 0x18)),
// CHECK: # Relocation 4
// CHECK: (('word-0', 0xa4000014),
-// CHECK: ('word-1', 0x14)),
+// CHECK: ('word-1', 0x1c)),
// CHECK: # Relocation 5
// CHECK: (('word-0', 0xa1000000),
-// CHECK: ('word-1', 0x1c)),
+// CHECK: ('word-1', 0x24)),
// CHECK: # Relocation 6
// CHECK: (('word-0', 0x8),
// CHECK: ('word-1', 0x4000002)),
// CHECK: # Relocation 7
// CHECK: (('word-0', 0x4),
-// CHECK: ('word-1', 0xc000006)),
+// CHECK: ('word-1', 0xc000007)),
// CHECK: # Relocation 8
// CHECK: (('word-0', 0x0),
-// CHECK: ('word-1', 0xc000006)),
+// CHECK: ('word-1', 0xc000007)),
// CHECK: ])
-// CHECK: ('_section_data', '\x00\x00\x00\x00\x04\x00\x00\x00\x08\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\xed\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x11\x00\x00\x00\x1a\x00\x00\x00$\x00i')
+// CHECK: ('_section_data', '\x00\x00\x00\x00\x04\x00\x00\x00\x10\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\xed\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x19\x00\x00\x00"\x00\x00\x00,\x00q')
// CHECK: # Section 2
// CHECK: (('section_name', '__const\x00\x00\x00\x00\x00\x00\x00\x00\x00')
// CHECK: ('segment_name', '__TEXT\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00')
-// CHECK: ('address', 43)
-// CHECK: ('size', 4)
-// CHECK: ('offset', 435)
+// CHECK: ('address', 51)
+// CHECK: ('size', 12)
+// CHECK: ('offset', 443)
// CHECK: ('alignment', 0)
-// CHECK: ('reloc_offset', 512)
-// CHECK: ('num_reloc', 2)
+// CHECK: ('reloc_offset', 536)
+// CHECK: ('num_reloc', 4)
// CHECK: ('flags', 0x0)
// CHECK: ('reserved1', 0)
// CHECK: ('reserved2', 0)
// CHECK: ),
// CHECK: ('_relocations', [
// CHECK: # Relocation 0
-// CHECK: (('word-0', 0xa4000000),
-// CHECK: ('word-1', 0x10)),
+// CHECK: (('word-0', 0x8),
+// CHECK: ('word-1', 0x4000001)),
// CHECK: # Relocation 1
+// CHECK: (('word-0', 0x4),
+// CHECK: ('word-1', 0x4000003)),
+// CHECK: # Relocation 2
+// CHECK: (('word-0', 0xa4000000),
+// CHECK: ('word-1', 0x18)),
+// CHECK: # Relocation 3
// CHECK: (('word-0', 0xa1000000),
-// CHECK: ('word-1', 0x2b)),
+// CHECK: ('word-1', 0x33)),
// CHECK: ])
-// CHECK: ('_section_data', '\x06\x00\x00\x00')
+// CHECK: ('_section_data', '\x06\x00\x00\x007\x00\x00\x00\x00\x00\x00\x00')
// CHECK: ])
// CHECK: ),
// CHECK: # Load Command 1
// CHECK: (('command', 2)
// CHECK: ('size', 24)
-// CHECK: ('symoff', 528)
-// CHECK: ('nsyms', 7)
-// CHECK: ('stroff', 612)
-// CHECK: ('strsize', 60)
-// CHECK: ('_string_data', '\x00undef\x00local_a_ext\x00local_a\x00local_a_elt\x00local_b\x00local_c\x00bar\x00\x00')
+// CHECK: ('symoff', 568)
+// CHECK: ('nsyms', 8)
+// CHECK: ('stroff', 664)
+// CHECK: ('strsize', 64)
+// CHECK: ('_string_data', '\x00undef\x00local_a_ext\x00local_a\x00local_a_elt\x00local_b\x00local_c\x00bar\x00_f0\x00\x00')
// CHECK: ('_symbols', [
// CHECK: # Symbol 0
// CHECK: (('n_strx', 19)
// CHECK: ('n_type', 0xe)
// CHECK: ('n_sect', 2)
// CHECK: ('n_desc', 0)
-// CHECK: ('n_value', 12)
+// CHECK: ('n_value', 20)
// CHECK: ('_string', 'local_a')
// CHECK: ),
// CHECK: # Symbol 1
@@ -155,7 +175,7 @@
// CHECK: ('n_type', 0xe)
// CHECK: ('n_sect', 2)
// CHECK: ('n_desc', 0)
-// CHECK: ('n_value', 16)
+// CHECK: ('n_value', 24)
// CHECK: ('_string', 'local_a_elt')
// CHECK: ),
// CHECK: # Symbol 2
@@ -163,7 +183,7 @@
// CHECK: ('n_type', 0xe)
// CHECK: ('n_sect', 2)
// CHECK: ('n_desc', 0)
-// CHECK: ('n_value', 20)
+// CHECK: ('n_value', 28)
// CHECK: ('_string', 'local_b')
// CHECK: ),
// CHECK: # Symbol 3
@@ -171,7 +191,7 @@
// CHECK: ('n_type', 0xe)
// CHECK: ('n_sect', 2)
// CHECK: ('n_desc', 0)
-// CHECK: ('n_value', 28)
+// CHECK: ('n_value', 36)
// CHECK: ('_string', 'local_c')
// CHECK: ),
// CHECK: # Symbol 4
@@ -179,18 +199,26 @@
// CHECK: ('n_type', 0xe)
// CHECK: ('n_sect', 3)
// CHECK: ('n_desc', 0)
-// CHECK: ('n_value', 43)
+// CHECK: ('n_value', 51)
// CHECK: ('_string', 'bar')
// CHECK: ),
// CHECK: # Symbol 5
+// CHECK: (('n_strx', 59)
+// CHECK: ('n_type', 0xe)
+// CHECK: ('n_sect', 1)
+// CHECK: ('n_desc', 0)
+// CHECK: ('n_value', 0)
+// CHECK: ('_string', '_f0')
+// CHECK: ),
+// CHECK: # Symbol 6
// CHECK: (('n_strx', 7)
// CHECK: ('n_type', 0xf)
// CHECK: ('n_sect', 2)
// CHECK: ('n_desc', 0)
-// CHECK: ('n_value', 8)
+// CHECK: ('n_value', 16)
// CHECK: ('_string', 'local_a_ext')
// CHECK: ),
-// CHECK: # Symbol 6
+// CHECK: # Symbol 7
// CHECK: (('n_strx', 1)
// CHECK: ('n_type', 0x1)
// CHECK: ('n_sect', 0)
@@ -204,10 +232,10 @@
// CHECK: (('command', 11)
// CHECK: ('size', 80)
// CHECK: ('ilocalsym', 0)
-// CHECK: ('nlocalsym', 5)
-// CHECK: ('iextdefsym', 5)
+// CHECK: ('nlocalsym', 6)
+// CHECK: ('iextdefsym', 6)
// CHECK: ('nextdefsym', 1)
-// CHECK: ('iundefsym', 6)
+// CHECK: ('iundefsym', 7)
// CHECK: ('nundefsym', 1)
// CHECK: ('tocoff', 0)
// CHECK: ('ntoc', 0)
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