3 files changed, 59 insertions, 0 deletions
diff --git a/lld/ELF/LinkerScript.cpp b/lld/ELF/LinkerScript.cpp
index 6a9d2ebca97..943a4abaff0 100644
--- a/lld/ELF/LinkerScript.cpp
+++ b/lld/ELF/LinkerScript.cpp
@@ -572,6 +572,15 @@ uint64_t LinkerScript<ELFT>::getOutputSectionSize(StringRef Name) {
   return 0;
 }
 
+template <class ELFT>
+uint64_t LinkerScript<ELFT>::getOutputSectionAlign(StringRef Name) {
+  for (OutputSectionBase<ELFT> *Sec : *OutputSections)
+    if (Sec->getName() == Name)
+      return Sec->getAlignment();
+  error("undefined section " + Name);
+  return 0;
+}
+
 template <class ELFT> uint64_t LinkerScript<ELFT>::getHeaderSize() {
   return Out<ELFT>::ElfHeader->getSize() + Out<ELFT>::ProgramHeaders->getSize();
 }
@@ -1306,6 +1315,13 @@ Expr ScriptParser::readPrimary() {
     expect(")");
     return [=](uint64_t Dot) { return ScriptBase->getOutputSectionSize(Name); };
   }
+  if (Tok == "ALIGNOF") {
+    expect("(");
+    StringRef Name = next();
+    expect(")");
+    return
+        [=](uint64_t Dot) { return ScriptBase->getOutputSectionAlign(Name); };
+  }
   if (Tok == "SIZEOF_HEADERS")
     return [=](uint64_t Dot) { return ScriptBase->getHeaderSize(); };
 
diff --git a/lld/ELF/LinkerScript.h b/lld/ELF/LinkerScript.h
index 5b4032467fe..a3732eef053 100644
--- a/lld/ELF/LinkerScript.h
+++ b/lld/ELF/LinkerScript.h
@@ -127,6 +127,7 @@ class LinkerScriptBase {
 public:
   virtual uint64_t getOutputSectionAddress(StringRef Name) = 0;
   virtual uint64_t getOutputSectionSize(StringRef Name) = 0;
+  virtual uint64_t getOutputSectionAlign(StringRef Name) = 0;
   virtual uint64_t getHeaderSize() = 0;
   virtual uint64_t getSymbolValue(StringRef S) = 0;
 };
@@ -173,6 +174,7 @@ public:
   bool hasPhdrsCommands();
   uint64_t getOutputSectionAddress(StringRef Name) override;
   uint64_t getOutputSectionSize(StringRef Name) override;
+  uint64_t getOutputSectionAlign(StringRef Name) override;
   uint64_t getHeaderSize() override;
   uint64_t getSymbolValue(StringRef S) override;
 
diff --git a/lld/test/ELF/linkerscript/alignof.s b/lld/test/ELF/linkerscript/alignof.s
new file mode 100644
index 00000000000..f530abd3393
--- /dev/null
+++ b/lld/test/ELF/linkerscript/alignof.s
@@ -0,0 +1,41 @@
+# REQUIRES: x86
+# RUN: llvm-mc -filetype=obj -triple=x86_64-unknown-linux %s -o %t
+
+# RUN: echo "SECTIONS { \
+# RUN:   .aaa         : { *(.aaa) } \
+# RUN:   .bbb         : { *(.bbb) } \
+# RUN:   .ccc         : { *(.ccc) } \
+# RUN:   _aaa = ALIGNOF(.aaa); \
+# RUN:   _bbb = ALIGNOF(.bbb); \
+# RUN:   _ccc = ALIGNOF(.ccc); \
+# RUN: }" > %t.script
+# RUN: ld.lld -o %t1 --script %t.script %t
+# RUN: llvm-objdump -t %t1 | FileCheck %s
+# CHECK:      SYMBOL TABLE:
+# CHECK:      0000000000000008         *ABS*     00000000 _aaa
+# CHECK-NEXT: 0000000000000010         *ABS*     00000000 _bbb
+# CHECK-NEXT: 0000000000000020         *ABS*     00000000 _ccc
+
+## Check that we error out if trying to get alignment of
+## section that does not exist.
+# RUN: echo "SECTIONS { \
+# RUN:   _aaa = ALIGNOF(.foo); \
+# RUN: }" > %t.script
+# RUN: not ld.lld -o %t1 --script %t.script %t 2>&1 \
+# RUN:  | FileCheck -check-prefix=ERR %s
+# ERR: undefined section .foo
+.global _start
+_start:
+ nop
+
+.section .aaa,"a"
+ .align 8
+ .quad 0
+
+.section .bbb,"a"
+ .align 16
+ .quad 0
+
+.section .ccc,"a"
+ .align 32
+ .quad 0