[ELF] - Fix for: bug 29115 - linkerscript does not support non-wildcard filename spec.

[grimar]

Summary

FreeBSD/mips script has non-wildcard filename specifications:

10	  .text      :
11	  {
12	    start.o(.text*)

The source linker script is here: https://svnweb.freebsd.org/base/head/sys/boot/mips/uboot/ldscript.mips?revision=296183&view=markup#l12

Patch adds support for that, this is PR29115.

[ruiu]

ELF/LinkerScript.cpp

952

So we no longer print out "unknown command" error, don't we? I think we want that error.

[grimar]

ELF/LinkerScript.cpp

952

I am not sure it is possible to recognize unknown command here. It can be just a name of file. If not then readInputSectionDescription() will report something.

[ruiu]

ELF/LinkerScript.cpp

952

A filename must be followed by '(', no?

[grimar]

ELF/LinkerScript.cpp

952

Yes and that is a problem. Because
filename.a [ ... )
does not mean that filename.a is a unknown command, but just means that input section description is incorrect.
So there is no good solution here I think. Though I can do such check here If you think it is better.

[grimar]

• Addressed review comments.

[ruiu]

LGTM

ELF/LinkerScript.cpp

private:
   void readPhdrs();
   void readSearchDir();
   void readSections();
 
   SymbolAssignment *readAssignment(StringRef Name);
   OutputSectionCommand *readOutputSectionDescription(StringRef OutSec);
   std::vector<uint8_t> readOutputSectionFiller();
   std::vector<StringRef> readOutputSectionPhdrs();
-  InputSectionDescription *readInputSectionDescription();
+  InputSectionDescription *readInputSectionDescription(StringRef Tok);
   std::vector<StringRef> readInputFilePatterns();
-  InputSectionDescription *readInputSectionRules();
+  InputSectionDescription *readInputSectionRules(StringRef FilePattern);
   unsigned readPhdrType();
   SortKind readSortKind();
   SymbolAssignment *readProvideHidden(bool Provide, bool Hidden);
   SymbolAssignment *readProvideOrAssignment(StringRef Tok);
   void readSort();
   Expr readAssert();
 
   Expr readExpr();

 SortKind ScriptParser::readSortKind() {
   if (skip("SORT") || skip("SORT_BY_NAME"))
     return SortByName;
   if (skip("SORT_BY_ALIGNMENT"))
     return SortByAlignment;
   return SortNone;
 }
 
-InputSectionDescription *ScriptParser::readInputSectionRules() {
+InputSectionDescription *
+ScriptParser::readInputSectionRules(StringRef FilePattern) {
   auto *Cmd = new InputSectionDescription;
-  Cmd->FilePattern = next();
+  Cmd->FilePattern = FilePattern;
   expect("(");
 
   // Read EXCLUDE_FILE().
   if (skip("EXCLUDE_FILE")) {
     expect("(");
     while (!Error && !skip(")"))
       Cmd->ExcludedFiles.push_back(next());
   }
if (SortKind K1 = readSortKind()) {
     expect(")");
     return Cmd;
   }
 
   Cmd->SectionPatterns = readInputFilePatterns();
   return Cmd;
 }
 
-InputSectionDescription *ScriptParser::readInputSectionDescription() {
+InputSectionDescription *
+ScriptParser::readInputSectionDescription(StringRef Tok) {
   // Input section wildcard can be surrounded by KEEP.
   // https://sourceware.org/binutils/docs/ld/Input-Section-Keep.html#Input-Section-Keep
-  if (skip("KEEP")) {
+  if (Tok == "KEEP") {
     expect("(");
-    InputSectionDescription *Cmd = readInputSectionRules();
+    StringRef FilePattern = next();
+    InputSectionDescription *Cmd = readInputSectionRules(FilePattern);
     expect(")");
     Opt.KeptSections.insert(Opt.KeptSections.end(),
                             Cmd->SectionPatterns.begin(),
                             Cmd->SectionPatterns.end());
     return Cmd;
   }
-  return readInputSectionRules();
+  return readInputSectionRules(Tok);
 }
 
 void ScriptParser::readSort() {
   expect("(");
   expect("CONSTRUCTORS");
   expect(")");
 }
 
ScriptParser::readOutputSectionDescription(StringRef OutSec) {
   // Parse constraints.
   if (skip("ONLY_IF_RO"))
     Cmd->Constraint = ConstraintKind::ReadOnly;
   if (skip("ONLY_IF_RW"))
     Cmd->Constraint = ConstraintKind::ReadWrite;
   expect("{");
 
   while (!Error && !skip("}")) {
-    if (peek().startswith("*") || peek() == "KEEP") {
-      Cmd->Commands.emplace_back(readInputSectionDescription());
-      continue;
-    }
-
     StringRef Tok = next();
     if (SymbolAssignment *Assignment = readProvideOrAssignment(Tok))
       Cmd->Commands.emplace_back(Assignment);
     else if (Tok == "SORT")
       readSort();
+    else if (peek() == "(")
+      Cmd->Commands.emplace_back(readInputSectionDescription(Tok));
     else
       setError("unknown command " + Tok);
   }
   Cmd->Phdrs = readOutputSectionPhdrs();
   Cmd->Filler = readOutputSectionFiller();
   return Cmd;
 }
 
 std::vector<uint8_t> ScriptParser::readOutputSectionFiller() {
   StringRef Tok = peek();

test/ELF/linkerscript/linkerscript-filename-spec.s

 # RUN: llvm-objdump -s %t3 | FileCheck --check-prefix=FIRSTSECOND %s
 
 # RUN: echo "SECTIONS { .foo : { \
 # RUN:   *second.o(.foo) \
 # RUN:   *first.o(.foo) } }" > %t4.script
 # RUN: ld.lld -o %t4 --script %t4.script %tfirst.o %tsecond.o
 # RUN: llvm-objdump -s %t4 | FileCheck --check-prefix=SECONDFIRST %s
 
+# RUN: llvm-mc -filetype=obj -triple=x86_64-unknown-linux %s -o %T/linkerscript-filename-spec1.o
+# RUN: llvm-mc -filetype=obj -triple=x86_64-unknown-linux \
+# RUN:   %p/Inputs/linkerscript-filename-spec.s -o %T/linkerscript-filename-spec2.o
+
+# RUN: echo "SECTIONS { .foo : { \
+# RUN:   linkerscript-filename-spec2.o(.foo) \
+# RUN:   linkerscript-filename-spec1.o(.foo) } }" > %t5.script
+# RUN: ld.lld -o %t5 --script %t5.script \
+# RUN:   %T/linkerscript-filename-spec1.o %T/linkerscript-filename-spec2.o
+# RUN: llvm-objdump -s %t5 | FileCheck --check-prefix=SECONDFIRST %s
+
+# RUN: echo "SECTIONS { .foo : { \
+# RUN:   linkerscript-filename-spec1.o(.foo) \
+# RUN:   linkerscript-filename-spec2.o(.foo) } }" > %t6.script
+# RUN: ld.lld -o %t6 --script %t6.script \
+# RUN:   %T/linkerscript-filename-spec1.o %T/linkerscript-filename-spec2.o
+# RUN: llvm-objdump -s %t6 | FileCheck --check-prefix=FIRSTSECOND %s
+
 .global _start
 _start:
  nop
 
 .section .foo,"a"
  .quad 1