Index: ELF/LinkerScript.h
===================================================================
--- ELF/LinkerScript.h
+++ ELF/LinkerScript.h
@@ -300,6 +300,9 @@
 extern LinkerScript *Script;
 
 } // end namespace elf
+
+void fill(uint8_t *Buf, size_t Size, uint32_t Filler);
+
 } // end namespace lld
 
 #endif // LLD_ELF_LINKER_SCRIPT_H
Index: ELF/LinkerScript.cpp
===================================================================
--- ELF/LinkerScript.cpp
+++ ELF/LinkerScript.cpp
@@ -165,7 +165,7 @@
 
 // Fill [Buf, Buf + Size) with Filler.
 // This is used for linker script "=fillexp" command.
-static void fill(uint8_t *Buf, size_t Size, uint32_t Filler) {
+void lld::fill(uint8_t *Buf, size_t Size, uint32_t Filler) {
   size_t I = 0;
   for (; I + 4 < Size; I += 4)
     memcpy(Buf + I, &Filler, 4);
Index: ELF/Writer.cpp
===================================================================
--- ELF/Writer.cpp
+++ ELF/Writer.cpp
@@ -66,6 +66,7 @@
   void fixSectionAlignments();
   void fixPredefinedSymbols();
   void openFile();
+  void writeTrapInstr();
   void writeHeader();
   void writeSections();
   void writeSectionsBinary();
@@ -245,6 +246,7 @@
     return;
 
   if (!Config->OFormatBinary) {
+    writeTrapInstr();
     writeHeader();
     writeSections();
   } else {
@@ -1629,15 +1631,35 @@
   FileSize = alignTo(Off, Config->Wordsize);
 }
 
+static std::vector<PhdrEntry *> getExecLoads(ArrayRef<PhdrEntry *> V) {
+  std::vector<PhdrEntry *> Ret;
+  for (PhdrEntry *Load : V)
+    if (Load->p_type == PT_LOAD && Load->p_flags & PF_X)
+      Ret.push_back(Load);
+  return Ret;
+}
+
 // Assign file offsets to output sections.
 template <class ELFT> void Writer<ELFT>::assignFileOffsets() {
   uint64_t Off = 0;
   Off = setOffset(Out::ElfHeader, Off);
   Off = setOffset(Out::ProgramHeaders, Off);
 
-  for (OutputSectionCommand *Cmd : OutputSectionCommands)
+  std::vector<PhdrEntry *> ExecLoads = getExecLoads(Phdrs);
+  OutputSection *LastExec =
+      ExecLoads.empty() ? nullptr : ExecLoads.back()->Last;
+  for (OutputSectionCommand *Cmd : OutputSectionCommands) {
     Off = setOffset(Cmd->Sec, Off);
 
+    // If no linker script is involved and allocatable section is the last in
+    // executable segment, that means we want to ensure segment contains only
+    // valid instructions and hence we align next section's offset to avoid
+    // loading of non-allocatable content. We will fill gap with trap op codes.
+    if (!Script->Opt.HasSections)
+      if (Cmd->Sec == LastExec)
+        Off = alignTo(Off, Target->PageSize);
+  }
+
   SectionHeaderOff = alignTo(Off, Config->Wordsize);
   FileSize =
       SectionHeaderOff + (OutputSectionCommands.size() + 1) * sizeof(Elf_Shdr);
@@ -1857,6 +1879,35 @@
   }
 }
 
+static void fillPage(uint8_t *Buf, uint64_t Offset, uint32_t Filler) {
+  uint64_t Begin = alignDown(Offset, Target->PageSize);
+  uint64_t End = alignTo(Offset, Target->PageSize);
+  fill(Buf + Begin, End - Begin, Filler);
+}
+
+template <class ELFT> void Writer<ELFT>::writeTrapInstr() {
+  // FIXME: do the same for case when sections present.
+  if (Script->Opt.HasSections)
+    return;
+
+  uint8_t *Buf = Buffer->getBufferStart();
+  for (PhdrEntry *Load : getExecLoads(Phdrs)) {
+    // We only fill the first and the last page of the segment because the
+    // middle part will be overwritten by output sections.
+    fillPage(Buf, Load->p_offset, Target->TrapInstr);
+    fillPage(Buf, Load->p_offset + Load->p_filesz, Target->TrapInstr);
+  }
+
+  // Round up the file size of the last segment to the page boundary if it is
+  // an executable segment to ensure that other other tools don't accidentally
+  // trim the instruction padding (e.g. when stripping the file).
+  auto It = llvm::find_if(llvm::reverse(Phdrs), [](PhdrEntry *Phdr) {
+    return Phdr->p_type == PT_LOAD;
+  });
+  if (It != Phdrs.rend() && (*It)->p_flags & PF_X)
+    (*It)->p_filesz = alignTo((*It)->p_filesz, Target->PageSize);
+}
+
 // Write section contents to a mmap'ed file.
 template <class ELFT> void Writer<ELFT>::writeSections() {
   uint8_t *Buf = Buffer->getBufferStart();
Index: test/ELF/avoid-empty-program-headers.s
===================================================================
--- test/ELF/avoid-empty-program-headers.s
+++ test/ELF/avoid-empty-program-headers.s
@@ -42,7 +42,7 @@
 // CHECK-NEXT:     Offset: 0x1000
 // CHECK-NEXT:     VirtualAddress: 0x201000
 // CHECK-NEXT:     PhysicalAddress: 0x201000
-// CHECK-NEXT:     FileSize: 1
+// CHECK-NEXT:     FileSize: 4096
 // CHECK-NEXT:     MemSize: 1
 // CHECK-NEXT:     Flags [ (0x5)
 // CHECK-NEXT:       PF_R (0x4)
@@ -52,7 +52,7 @@
 // CHECK-NEXT:   }
 // CHECK-NEXT:   ProgramHeader {
 // CHECK-NEXT:     Type: PT_TLS (0x7)
-// CHECK-NEXT:     Offset: 0x1001
+// CHECK-NEXT:     Offset: 0x2000
 // CHECK-NEXT:     VirtualAddress: 0x201001
 // CHECK-NEXT:     PhysicalAddress: 0x201001
 // CHECK-NEXT:     FileSize: 0
Index: test/ELF/basic-aarch64.s
===================================================================
--- test/ELF/basic-aarch64.s
+++ test/ELF/basic-aarch64.s
@@ -26,7 +26,7 @@
 # CHECK-NEXT:   Version: 1
 # CHECK-NEXT:   Entry: [[ENTRY:0x[0-9A-F]+]]
 # CHECK-NEXT:   ProgramHeaderOffset: 0x40
-# CHECK-NEXT:   SectionHeaderOffset: 0x10098
+# CHECK-NEXT:   SectionHeaderOffset: 0x11088
 # CHECK-NEXT:   Flags [ (0x0)
 # CHECK-NEXT:   ]
 # CHECK-NEXT:   HeaderSize: 64
@@ -76,7 +76,7 @@
 # CHECK-NEXT:       SHF_STRINGS (0x20)
 # CHECK-NEXT:     ]
 # CHECK-NEXT:     Address: 0x0
-# CHECK-NEXT:     Offset: 0x1000C
+# CHECK-NEXT:     Offset: 0x11000
 # CHECK-NEXT:     Size: 8
 # CHECK-NEXT:     Link: 0
 # CHECK-NEXT:     Info: 0
@@ -90,7 +90,7 @@
 # CHECK-NEXT:     Flags [ (0x0)
 # CHECK-NEXT:     ]
 # CHECK-NEXT:     Address: 0x0
-# CHECK-NEXT:     Offset: 0x10018
+# CHECK-NEXT:     Offset: 0x11008
 # CHECK-NEXT:     Size: 72
 # CHECK-NEXT:     Link: 5
 # CHECK-NEXT:     Info: 2
@@ -104,7 +104,7 @@
 # CHECK-NEXT:     Flags [ (0x0)
 # CHECK-NEXT:     ]
 # CHECK-NEXT:     Address: 0x0
-# CHECK-NEXT:     Offset: 0x10060
+# CHECK-NEXT:     Offset: 0x11050
 # CHECK-NEXT:     Size: 42
 # CHECK-NEXT:     Link: 0
 # CHECK-NEXT:     Info: 0
@@ -118,7 +118,7 @@
 # CHECK-NEXT:     Flags [ (0x0)
 # CHECK-NEXT:     ]
 # CHECK-NEXT:     Address: 0x0
-# CHECK-NEXT:     Offset: 0x1008A
+# CHECK-NEXT:     Offset: 0x1107A
 # CHECK-NEXT:     Size: 13
 # CHECK-NEXT:     Link: 0
 # CHECK-NEXT:     Info: 0
@@ -185,7 +185,7 @@
 # CHECK-NEXT:     Offset: 0x1000
 # CHECK-NEXT:     VirtualAddress: 0x20000
 # CHECK-NEXT:     PhysicalAddress: 0x20000
-# CHECK-NEXT:     FileSize: 12
+# CHECK-NEXT:     FileSize: 4096
 # CHECK-NEXT:     MemSize: 12
 # CHECK-NEXT:     Flags [ (0x5)
 # CHECK-NEXT:       PF_R (0x4)
Index: test/ELF/basic-sparcv9.s
===================================================================
--- test/ELF/basic-sparcv9.s
+++ test/ELF/basic-sparcv9.s
@@ -26,7 +26,7 @@
 # CHECK-NEXT:   Version: 1
 # CHECK-NEXT:   Entry: [[ENTRY:0x[0-9A-F]+]]
 # CHECK-NEXT:   ProgramHeaderOffset: 0x40
-# CHECK-NEXT:   SectionHeaderOffset: 0x100080
+# CHECK-NEXT:   SectionHeaderOffset: 0x102070
 # CHECK-NEXT:   Flags [ (0x0)
 # CHECK-NEXT:   ]
 # CHECK-NEXT:   HeaderSize: 64
@@ -76,7 +76,7 @@
 # CHECK-NEXT:       SHF_STRINGS (0x20)
 # CHECK-NEXT:     ]
 # CHECK-NEXT:     Address: 0x0
-# CHECK-NEXT:     Offset: 0x10000C
+# CHECK-NEXT:     Offset: 0x102000
 # CHECK-NEXT:     Size: 8
 # CHECK-NEXT:     Link: 0
 # CHECK-NEXT:     Info: 0
@@ -90,7 +90,7 @@
 # CHECK-NEXT:     Flags [ (0x0)
 # CHECK-NEXT:     ]
 # CHECK-NEXT:     Address: 0x0
-# CHECK-NEXT:     Offset: 0x100018
+# CHECK-NEXT:     Offset: 0x102008
 # CHECK-NEXT:     Size: 48
 # CHECK-NEXT:     Link: 5
 # CHECK-NEXT:     Info: 1
@@ -104,7 +104,7 @@
 # CHECK-NEXT:     Flags [ (0x0)
 # CHECK-NEXT:     ]
 # CHECK-NEXT:     Address: 0x0
-# CHECK-NEXT:     Offset: 0x100048
+# CHECK-NEXT:     Offset: 0x102038
 # CHECK-NEXT:     Size: 42
 # CHECK-NEXT:     Link: 0
 # CHECK-NEXT:     Info: 0
@@ -118,7 +118,7 @@
 # CHECK-NEXT:     Flags [ (0x0)
 # CHECK-NEXT:     ]
 # CHECK-NEXT:     Address: 0x0
-# CHECK-NEXT:     Offset: 0x100072
+# CHECK-NEXT:     Offset: 0x102062
 # CHECK-NEXT:     Size: 8
 # CHECK-NEXT:     Link: 0
 # CHECK-NEXT:     Info: 0
@@ -176,7 +176,7 @@
 # CHECK-NEXT:     Offset: 0x100000
 # CHECK-NEXT:     VirtualAddress: 0x200000
 # CHECK-NEXT:     PhysicalAddress: 0x200000
-# CHECK-NEXT:     FileSize: 12
+# CHECK-NEXT:     FileSize: 8192
 # CHECK-NEXT:     MemSize: 12
 # CHECK-NEXT:     Flags [ (0x5)
 # CHECK-NEXT:       PF_R (0x4)
Index: test/ELF/basic.s
===================================================================
--- test/ELF/basic.s
+++ test/ELF/basic.s
@@ -28,7 +28,7 @@
 # CHECK-NEXT:   Version: 1
 # CHECK-NEXT:   Entry: [[ENTRY:0x[0-9A-F]+]]
 # CHECK-NEXT:   ProgramHeaderOffset: 0x40
-# CHECK-NEXT:   SectionHeaderOffset: 0x1080
+# CHECK-NEXT:   SectionHeaderOffset: 0x2070
 # CHECK-NEXT:   Flags [ (0x0)
 # CHECK-NEXT:   ]
 # CHECK-NEXT:   HeaderSize: 64
@@ -78,7 +78,7 @@
 # CHECK-NEXT:       SHF_STRINGS (0x20)
 # CHECK-NEXT:     ]
 # CHECK-NEXT:     Address: 0x0
-# CHECK-NEXT:     Offset: 0x1010
+# CHECK-NEXT:     Offset: 0x2000
 # CHECK-NEXT:     Size: 8
 # CHECK-NEXT:     Link: 0
 # CHECK-NEXT:     Info: 0
@@ -92,7 +92,7 @@
 # CHECK-NEXT:     Flags [ (0x0)
 # CHECK-NEXT:     ]
 # CHECK-NEXT:     Address: 0x0
-# CHECK-NEXT:     Offset: 0x1018
+# CHECK-NEXT:     Offset: 0x2008
 # CHECK-NEXT:     Size: 48
 # CHECK-NEXT:     Link: 5
 # CHECK-NEXT:     Info: 1
@@ -106,7 +106,7 @@
 # CHECK-NEXT:     Flags [ (0x0)
 # CHECK-NEXT:     ]
 # CHECK-NEXT:     Address: 0x0
-# CHECK-NEXT:     Offset: 0x1048
+# CHECK-NEXT:     Offset: 0x2038
 # CHECK-NEXT:     Size: 42
 # CHECK-NEXT:     Link: 0
 # CHECK-NEXT:     Info: 0
@@ -120,7 +120,7 @@
 # CHECK-NEXT:     Flags [ (0x0)
 # CHECK-NEXT:     ]
 # CHECK-NEXT:     Address: 0x0
-# CHECK-NEXT:     Offset: 0x1072
+# CHECK-NEXT:     Offset: 0x2062
 # CHECK-NEXT:     Size: 8
 # CHECK-NEXT:     Link: 0
 # CHECK-NEXT:     Info: 0
@@ -178,7 +178,7 @@
 # CHECK-NEXT:     Offset: 0x1000
 # CHECK-NEXT:     VirtualAddress: 0x201000
 # CHECK-NEXT:     PhysicalAddress: 0x201000
-# CHECK-NEXT:     FileSize: 16
+# CHECK-NEXT:     FileSize: 4096
 # CHECK-NEXT:     MemSize: 16
 # CHECK-NEXT:     Flags [ (0x5)
 # CHECK-NEXT:       PF_R (0x4)
Index: test/ELF/basic32.s
===================================================================
--- test/ELF/basic32.s
+++ test/ELF/basic32.s
@@ -25,7 +25,7 @@
 # CHECK-NEXT:   Version: 1
 # CHECK-NEXT:   Entry: 0x11000
 # CHECK-NEXT:   ProgramHeaderOffset: 0x34
-# CHECK-NEXT:   SectionHeaderOffset: 0x1068
+# CHECK-NEXT:   SectionHeaderOffset: 0x205C
 # CHECK-NEXT:   Flags [ (0x0)
 # CHECK-NEXT:   ]
 # CHECK-NEXT:   HeaderSize: 52
@@ -75,7 +75,7 @@
 # CHECK-NEXT:       SHF_STRINGS (0x20)
 # CHECK-NEXT:     ]
 # CHECK-NEXT:     Address: 0x0
-# CHECK-NEXT:     Offset: 0x100C
+# CHECK-NEXT:     Offset: 0x2000
 # CHECK-NEXT:     Size: 8
 # CHECK-NEXT:     Link: 0
 # CHECK-NEXT:     Info: 0
@@ -89,7 +89,7 @@
 # CHECK-NEXT:     Flags [
 # CHECK-NEXT:     ]
 # CHECK-NEXT:     Address: 0x0
-# CHECK-NEXT:     Offset: 0x1014
+# CHECK-NEXT:     Offset: 0x2008
 # CHECK-NEXT:     Size: 32
 # CHECK-NEXT:     Link: 5
 # CHECK-NEXT:     Info: 1
@@ -103,7 +103,7 @@
 # CHECK-NEXT:     Flags [ (0x0)
 # CHECK-NEXT:     ]
 # CHECK-NEXT:     Address: 0x0
-# CHECK-NEXT:     Offset: 0x1034
+# CHECK-NEXT:     Offset: 0x2028
 # CHECK-NEXT:     Size: 42
 # CHECK-NEXT:     Link: 0
 # CHECK-NEXT:     Info: 0
@@ -117,7 +117,7 @@
 # CHECK-NEXT:     Flags [ (0x0)
 # CHECK-NEXT:     ]
 # CHECK-NEXT:     Address: 0x0
-# CHECK-NEXT:     Offset: 0x105E
+# CHECK-NEXT:     Offset: 0x2052
 # CHECK-NEXT:     Size: 8
 # CHECK-NEXT:     Link: 0
 # CHECK-NEXT:     Info: 0
@@ -155,7 +155,7 @@
 # CHECK-NEXT:     Offset: 0x1000
 # CHECK-NEXT:     VirtualAddress: 0x11000
 # CHECK-NEXT:     PhysicalAddress: 0x11000
-# CHECK-NEXT:     FileSize: 12
+# CHECK-NEXT:     FileSize: 4096
 # CHECK-NEXT:     MemSize: 12
 # CHECK-NEXT:     Flags [ (0x5)
 # CHECK-NEXT:       PF_R (0x4)
Index: test/ELF/build-id.s
===================================================================
--- test/ELF/build-id.s
+++ test/ELF/build-id.s
@@ -48,7 +48,7 @@
 # DEFAULT:      Contents of section .note.test:
 # DEFAULT:      Contents of section .note.gnu.build-id:
 # DEFAULT-NEXT: 04000000 08000000 03000000 474e5500  ............GNU.
-# DEFAULT-NEXT: fd36edb1 f6ff02af
+# DEFAULT-NEXT: b0148597 ba5eb7e9
 
 # MD5:      Contents of section .note.gnu.build-id:
 # MD5-NEXT: 04000000 10000000 03000000 474e5500  ............GNU.
@@ -56,7 +56,7 @@
 
 # SHA1:      Contents of section .note.gnu.build-id:
 # SHA1-NEXT: 04000000 14000000 03000000 474e5500  ............GNU.
-# SHA1-NEXT: 55b1eedb 03b588e1 09987d1d e9a79be7
+# SHA1-NEXT: 2f716666 fe3668fe 370a02a1 579c3eb2
 
 # UUID:      Contents of section .note.gnu.build-id:
 # UUID-NEXT: 04000000 10000000 03000000 474e5500  ............GNU.
Index: test/ELF/image-base.s
===================================================================
--- test/ELF/image-base.s
+++ test/ELF/image-base.s
@@ -44,7 +44,7 @@
 # CHECK-NEXT:     Offset: 0x1000
 # CHECK-NEXT:     VirtualAddress: 0x1001000
 # CHECK-NEXT:     PhysicalAddress: 0x1001000
-# CHECK-NEXT:     FileSize: 1
+# CHECK-NEXT:     FileSize: 4096
 # CHECK-NEXT:     MemSize: 1
 # CHECK-NEXT:     Flags [ (0x5)
 # CHECK-NEXT:       PF_R (0x4)
Index: test/ELF/relocatable.s
===================================================================
--- test/ELF/relocatable.s
+++ test/ELF/relocatable.s
@@ -81,7 +81,7 @@
 # CHECKEXE-NEXT:    Version: 1
 # CHECKEXE-NEXT:    Entry: 0x201000
 # CHECKEXE-NEXT:    ProgramHeaderOffset: 0x40
-# CHECKEXE-NEXT:    SectionHeaderOffset: 0x11F8
+# CHECKEXE-NEXT:    SectionHeaderOffset: 0x21A0
 # CHECKEXE-NEXT:    Flags [
 # CHECKEXE-NEXT:    ]
 # CHECKEXE-NEXT:    HeaderSize: 64