vendor/lld/lld-release_60-r321788

11 files changed, 146 insertions, 21 deletions

diff --git a/ELF/Driver.cpp b/ELF/Driver.cpp
index cc76fea2ad5e..b159fe63eb18 100644
--- a/ELF/Driver.cpp
+++ b/ELF/Driver.cpp
@@ -1043,7 +1043,8 @@ template <class ELFT> void LinkerDriver::link(opt::InputArgList &Args) {
     return;
 
   // Handle undefined symbols in DSOs.
-  Symtab->scanShlibUndefined<ELFT>();
+  if (!Config->Shared)
+    Symtab->scanShlibUndefined<ELFT>();
 
   // Handle the -exclude-libs option.
   if (Args.hasArg(OPT_exclude_libs))
diff --git a/ELF/Relocations.cpp b/ELF/Relocations.cpp
index 1aa0957b1d01..37bc8bcbd571 100644
--- a/ELF/Relocations.cpp
+++ b/ELF/Relocations.cpp
@@ -367,7 +367,7 @@ static bool isRelExpr(RelExpr Expr) {
 static bool isStaticLinkTimeConstant(RelExpr E, RelType Type, const Symbol &Sym,
                                      InputSectionBase &S, uint64_t RelOff) {
   // These expressions always compute a constant
-  if (isRelExprOneOf<R_SIZE, R_GOT_FROM_END, R_GOT_OFF, R_MIPS_GOT_LOCAL_PAGE,
+  if (isRelExprOneOf<R_GOT_FROM_END, R_GOT_OFF, R_MIPS_GOT_LOCAL_PAGE,
                      R_MIPS_GOT_OFF, R_MIPS_GOT_OFF32, R_MIPS_GOT_GP_PC,
                      R_MIPS_TLSGD, R_GOT_PAGE_PC, R_GOT_PC, R_GOTONLY_PC,
                      R_GOTONLY_PC_FROM_END, R_PLT_PC, R_TLSGD_PC, R_TLSGD,
@@ -384,6 +384,10 @@ static bool isStaticLinkTimeConstant(RelExpr E, RelType Type, const Symbol &Sym,
   if (!Config->Pic)
     return true;
 
+  // The size of a non preemptible symbol is a constant.
+  if (E == R_SIZE)
+    return true;
+
   // For the target and the relocation, we want to know if they are
   // absolute or relative.
   bool AbsVal = isAbsoluteValue(Sym);
@@ -592,6 +596,12 @@ static RelExpr adjustExpr(Symbol &Sym, RelExpr Expr, RelType Type,
   if (IsConstant)
     return Expr;
 
+  // We can create any dynamic relocation supported by the dynamic linker if a
+  // section is writable or we are passed -z notext.
+  bool CanWrite = (S.Flags & SHF_WRITE) || !Config->ZText;
+  if (CanWrite && Target->isPicRel(Type))
+    return Expr;
+
   // If the relocation is to a weak undef, and we are producing
   // executable, give up on it and produce a non preemptible 0.
   if (!Config->Shared && Sym.isUndefWeak()) {
@@ -600,12 +610,6 @@ static RelExpr adjustExpr(Symbol &Sym, RelExpr Expr, RelType Type,
     return Expr;
   }
 
-  // We can create any dynamic relocation supported by the dynamic linker if a
-  // section is writable or we are passed -z notext.
-  bool CanWrite = (S.Flags & SHF_WRITE) || !Config->ZText;
-  if (CanWrite && Target->isPicRel(Type))
-    return Expr;
-
   // If we got here we know that this relocation would require the dynamic
   // linker to write a value to read only memory or use an unsupported
   // relocation.
diff --git a/ELF/SyntheticSections.cpp b/ELF/SyntheticSections.cpp
index a5e291b79a4d..f878acf8cf3f 100644
--- a/ELF/SyntheticSections.cpp
+++ b/ELF/SyntheticSections.cpp
@@ -1064,7 +1064,7 @@ template <class ELFT> void DynamicSection<ELFT>::finalizeContents() {
     addInt(DT_DEBUG, 0);
 
   this->Link = InX::DynStrTab->getParent()->SectionIndex;
-  if (InX::RelaDyn->getParent() && !InX::RelaDyn->empty()) {
+  if (!InX::RelaDyn->empty()) {
     addInSec(InX::RelaDyn->DynamicTag, InX::RelaDyn);
     addSize(InX::RelaDyn->SizeDynamicTag, InX::RelaDyn->getParent());
 
@@ -1081,7 +1081,13 @@ template <class ELFT> void DynamicSection<ELFT>::finalizeContents() {
         addInt(IsRela ? DT_RELACOUNT : DT_RELCOUNT, NumRelativeRels);
     }
   }
-  if (InX::RelaPlt->getParent() && !InX::RelaPlt->empty()) {
+  // .rel[a].plt section usually consists of two parts, containing plt and
+  // iplt relocations. It is possible to have only iplt relocations in the
+  // output. In that case RelaPlt is empty and have zero offset, the same offset
+  // as RelaIplt have. And we still want to emit proper dynamic tags for that
+  // case, so here we always use RelaPlt as marker for the begining of
+  // .rel[a].plt section.
+  if (InX::RelaPlt->getParent()->Live) {
     addInSec(DT_JMPREL, InX::RelaPlt);
     addSize(DT_PLTRELSZ, InX::RelaPlt->getParent());
     switch (Config->EMachine) {
diff --git a/ELF/Writer.cpp b/ELF/Writer.cpp
index 15f382104756..24c3e1ee207c 100644
--- a/ELF/Writer.cpp
+++ b/ELF/Writer.cpp
@@ -1767,30 +1767,36 @@ template <class ELFT> void Writer<ELFT>::fixSectionAlignments() {
 // virtual address (modulo the page size) so that the loader can load
 // executables without any address adjustment.
 static uint64_t getFileAlignment(uint64_t Off, OutputSection *Cmd) {
-  // If the section is not in a PT_LOAD, we just have to align it.
-  if (!Cmd->PtLoad)
-    return alignTo(Off, Cmd->Alignment);
-
-  OutputSection *First = Cmd->PtLoad->FirstSec;
+  OutputSection *First = Cmd->PtLoad ? Cmd->PtLoad->FirstSec : nullptr;
   // The first section in a PT_LOAD has to have congruent offset and address
   // module the page size.
   if (Cmd == First)
     return alignTo(Off, std::max<uint64_t>(Cmd->Alignment, Config->MaxPageSize),
                    Cmd->Addr);
 
+  // For SHT_NOBITS we don't want the alignment of the section to impact the
+  // offset of the sections that follow. Since nothing seems to care about the
+  // sh_offset of the SHT_NOBITS section itself, just ignore it.
+  if (Cmd->Type == SHT_NOBITS)
+    return Off;
+
+  // If the section is not in a PT_LOAD, we just have to align it.
+  if (!Cmd->PtLoad)
+    return alignTo(Off, Cmd->Alignment);
+
   // If two sections share the same PT_LOAD the file offset is calculated
   // using this formula: Off2 = Off1 + (VA2 - VA1).
   return First->Offset + Cmd->Addr - First->Addr;
 }
 
 static uint64_t setOffset(OutputSection *Cmd, uint64_t Off) {
-  if (Cmd->Type == SHT_NOBITS) {
-    Cmd->Offset = Off;
-    return Off;
-  }
-
   Off = getFileAlignment(Off, Cmd);
   Cmd->Offset = Off;
+
+  // For SHT_NOBITS we should not count the size.
+  if (Cmd->Type == SHT_NOBITS)
+    return Off;
+
   return Off + Cmd->Size;
 }
 
diff --git a/docs/ReleaseNotes.rst b/docs/ReleaseNotes.rst
index dcd6ac0602d3..e7ea0c8845fd 100644
--- a/docs/ReleaseNotes.rst
+++ b/docs/ReleaseNotes.rst
@@ -29,7 +29,13 @@ ELF Improvements
 COFF Improvements
 -----------------
 
-* Item 1.
+* A GNU ld style frontend for the COFF linker has been added for MinGW.
+  In MinGW environments, the linker is invoked with GNU ld style parameters;
+  which LLD previously only supported when used as an ELF linker. When
+  a PE/COFF target is chosen, those parameters are rewritten into the
+  lld-link style parameters and the COFF linker is invoked instead.
+
+* Initial support for the ARM64 architecture has been added.
 
 MachO Improvements
 ------------------
diff --git a/test/ELF/Inputs/shlib-undefined-ref.s b/test/ELF/Inputs/shlib-undefined-ref.s
new file mode 100644
index 000000000000..cfb7c60ebc01
--- /dev/null
+++ b/test/ELF/Inputs/shlib-undefined-ref.s
@@ -0,0 +1,4 @@
+.globl f
+f:
+	call	should_not_be_exported@PLT
+	ret
diff --git a/test/ELF/gnu-ifunc-dyntags.s b/test/ELF/gnu-ifunc-dyntags.s
new file mode 100644
index 000000000000..81bd338d088d
--- /dev/null
+++ b/test/ELF/gnu-ifunc-dyntags.s
@@ -0,0 +1,41 @@
+# REQUIRES: x86
+# RUN: llvm-mc -filetype=obj -triple=x86_64-pc-linux %s -o %t.o
+# RUN: ld.lld -pie %t.o -o %tout
+# RUN: llvm-objdump -section-headers %tout | FileCheck %s
+# RUN: llvm-readobj -dynamic-table -r %tout | FileCheck %s --check-prefix=TAGS
+
+## Check we produce DT_PLTREL/DT_JMPREL/DT_PLTGOT and DT_PLTRELSZ tags
+## when there are no other relocations except R_*_IRELATIVE.
+
+# CHECK:  Name          Size      Address
+# CHECK:  .rela.plt   00000030 0000000000000210
+# CHECK:  .got.plt    00000010 0000000000002000
+
+# TAGS:      Relocations [
+# TAGS-NEXT:   Section {{.*}} .rela.plt {
+# TAGS-NEXT:     R_X86_64_IRELATIVE
+# TAGS-NEXT:     R_X86_64_IRELATIVE
+# TAGS-NEXT:   }
+# TAGS-NEXT: ]
+
+# TAGS:   Tag                Type                 Name/Value
+# TAGS:   0x0000000000000017 JMPREL               0x210
+# TAGS:   0x0000000000000002 PLTRELSZ             48
+# TAGS:   0x0000000000000003 PLTGOT               0x2000
+# TAGS:   0x0000000000000014 PLTREL               RELA
+
+.text
+.type foo STT_GNU_IFUNC
+.globl foo
+foo:
+ ret
+
+.type bar STT_GNU_IFUNC
+.globl bar
+bar:
+ ret
+
+.globl _start
+_start:
+ call foo
+ call bar
diff --git a/test/ELF/linkerscript/nobits-offset.s b/test/ELF/linkerscript/nobits-offset.s
new file mode 100644
index 000000000000..c4141487630b
--- /dev/null
+++ b/test/ELF/linkerscript/nobits-offset.s
@@ -0,0 +1,18 @@
+# REQUIRES: x86
+# RUN: llvm-mc -filetype=obj -triple=x86_64-pc-linux %s -o %t.o
+# RUN: echo "SECTIONS { \
+# RUN:         .sec1 (NOLOAD) : { . += 1; } \
+# RUN:         .text          : { *(.text) } \
+# RUN:       };" > %t.script
+# RUN: ld.lld %t.o -T %t.script -o %t
+# RUN: llvm-readelf --sections %t | FileCheck %s
+
+# We used to misalign section offsets if the first section in a
+# PT_LOAD was SHT_NOBITS.
+
+# CHECK: [ 2] .text  PROGBITS  0000000000000010 001010 000010 00  AX  0   0 16
+
+.global _start
+_start:
+  nop
+.p2align 4
diff --git a/test/ELF/relocation-size-err.s b/test/ELF/relocation-size-err.s
new file mode 100644
index 000000000000..7bef45b66047
--- /dev/null
+++ b/test/ELF/relocation-size-err.s
@@ -0,0 +1,12 @@
+// REQUIRES: x86
+// RUN: llvm-mc -filetype=obj -triple=x86_64-pc-linux %s -o %t.o
+// RUN: not ld.lld %t.o -o %t.so -shared 2>&1 | FileCheck %s
+
+// CHECK:  error: can't create dynamic relocation R_X86_64_SIZE64 against symbol: foo in readonly segment; recompile object files with -fPIC
+
+        .global foo
+foo:
+        .quad 42
+        .size foo, 8
+
+        .quad foo@SIZE
diff --git a/test/ELF/shlib-undefined-shared.s b/test/ELF/shlib-undefined-shared.s
new file mode 100644
index 000000000000..6d60d01bfabe
--- /dev/null
+++ b/test/ELF/shlib-undefined-shared.s
@@ -0,0 +1,15 @@
+# REQUIRES: x86
+
+# RUN: llvm-mc -filetype=obj -triple=x86_64-linux-gnu -o %t1.o %S/Inputs/shlib-undefined-ref.s
+# RUN: ld.lld -shared -o %t1.so %t1.o
+
+# RUN: llvm-mc -filetype=obj -triple=x86_64-linux-gnu -o %t2.o %s
+# RUN: echo "{ local: *; };" > %t.script
+# RUN: ld.lld -shared -version-script %t.script -o %t2.so %t2.o %t1.so
+# RUN: llvm-nm -g %t2.so | FileCheck -allow-empty %s
+
+# CHECK-NOT: should_not_be_exported
+
+.globl should_not_be_exported
+should_not_be_exported:
+	ret
diff --git a/test/ELF/weak-undef-rw.s b/test/ELF/weak-undef-rw.s
new file mode 100644
index 000000000000..c75e7d67db3d
--- /dev/null
+++ b/test/ELF/weak-undef-rw.s
@@ -0,0 +1,12 @@
+# REQUIRES: x86
+# RUN: llvm-mc -filetype=obj -triple=x86_64-pc-linux %s -o %t.o
+# RUN: ld.lld %t.o -o %t --export-dynamic
+# RUN: llvm-readobj -r %t | FileCheck %s
+
+# CHECK: R_X86_64_64 foobar 0x0
+
+        .global _start
+_start:
+        .data
+        .weak foobar
+        .quad foobar