[lld][ELF] Handle archive special casing in Input Sections (llvm#119293)

According to the binutils spec:
https://sourceware.org/binutils/docs/ld/Input-Section-Basics.html

You should be able to specify all files in an archive using this syntax
`archivename:` , however, lld currently will only accept `archivename:*`
to match all files within an archive.

This patch will, only when necessary, create a copy of the file
specification and add an implicit wildcard `*` to the end. It also
updates the filename-spec linkerscript test to check for this behavior.

---------

Co-authored-by: Peter Smith <[email protected]>

Author: amosher-nvidia

lld/ELF/LinkerScript.cpp

@@ -406,8 +406,16 @@ bool InputSectionDescription::matchesFile(const InputFile &file) const {
   if (filePat.isTrivialMatchAll())
     return true;
 
-  if (!matchesFileCache || matchesFileCache->first != &file)
-    matchesFileCache.emplace(&file, filePat.match(file.getNameForScript()));
+  if (!matchesFileCache || matchesFileCache->first != &file) {
+    if (matchType == MatchType::WholeArchive) {
+      matchesFileCache.emplace(&file, filePat.match(file.archiveName));
+    } else {
+      if (matchType == MatchType::ArchivesExcluded && !file.archiveName.empty())
+        matchesFileCache.emplace(&file, false);
+      else
+        matchesFileCache.emplace(&file, filePat.match(file.getNameForScript()));
+    }
+  }
 
   return matchesFileCache->second;
 }

lld/ELF/LinkerScript.h

@@ -194,6 +194,7 @@ class SectionPattern {
 };
 
 class InputSectionDescription : public SectionCommand {
+  enum class MatchType { Trivial, WholeArchive, ArchivesExcluded } matchType;
   SingleStringMatcher filePat;
 
   // Cache of the most recent input argument and result of matchesFile().
@@ -202,10 +203,24 @@ class InputSectionDescription : public SectionCommand {
 public:
   InputSectionDescription(StringRef filePattern, uint64_t withFlags = 0,
                           uint64_t withoutFlags = 0, StringRef classRef = {})
-      : SectionCommand(InputSectionKind), filePat(filePattern),
-        classRef(classRef), withFlags(withFlags), withoutFlags(withoutFlags) {
+      : SectionCommand(InputSectionKind), matchType(MatchType::Trivial),
+        filePat(filePattern), classRef(classRef), withFlags(withFlags),
+        withoutFlags(withoutFlags) {
     assert((filePattern.empty() || classRef.empty()) &&
            "file pattern and class reference are mutually exclusive");
+
+    // The matching syntax for whole archives and files outside of an archive
+    // can't be handled by SingleStringMatcher, and instead are handled
+    // manually within matchesFile()
+    if (!filePattern.empty()) {
+      if (filePattern.back() == ':') {
+        matchType = MatchType::WholeArchive;
+        filePat = filePattern.drop_back();
+      } else if (filePattern.front() == ':') {
+        matchType = MatchType::ArchivesExcluded;
+        filePat = filePattern.drop_front();
+      }
+    }
   }
 
   static bool classof(const SectionCommand *c) {

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

@@ -4,7 +4,7 @@
 # RUN: llvm-mc -filetype=obj -triple=x86_64 tx.s -o tx.o
 # RUN: llvm-mc -filetype=obj -triple=x86_64 ty.s -o ty.o
 
-# RUN: echo 'SECTIONS{.foo :{ KEEP(*x.o(.foo)) KEEP(*y.o(.foo)) }}' > 1.t
+# RUN: echo 'SECTIONS{.foo :{ KEEP(:*x.o(.foo)) KEEP(*y.o(.foo)) }}' > 1.t
 # RUN: ld.lld -o 1 -T 1.t tx.o ty.o
 # RUN: llvm-objdump -s 1 | FileCheck --check-prefix=FIRSTY %s
 # FIRSTY:      Contents of section .foo:
@@ -18,7 +18,7 @@
 
 ## Now the same tests but without KEEP. Checking that file name inside
 ## KEEP is parsed fine.
-# RUN: echo 'SECTIONS{.foo :{ *x.o(.foo) *y.o(.foo) }}' > 3.t
+# RUN: echo 'SECTIONS{.foo :{ :*x.o(.foo) *y.o(.foo) }}' > 3.t
 # RUN: ld.lld -o 3 -T 3.t tx.o ty.o
 # RUN: llvm-objdump -s 3 | FileCheck --check-prefix=FIRSTY %s
 
@@ -41,6 +41,7 @@
 # RUN: cp ty.o dir2/filename-spec2.o
 # RUN: llvm-ar rc dir1/lib1.a dir1/filename-spec1.o
 # RUN: llvm-ar rc dir2/lib2.a dir2/filename-spec2.o
+# RUN: llvm-ar rc combined.a tx.o ty.o
 
 ## Verify matching of archive library names.
 # RUN: echo 'SECTIONS{.foo :{ *lib2*(.foo) *lib1*(.foo) }}' > 7.t
@@ -55,7 +56,7 @@
 # RUN: llvm-objdump -s 8 | FileCheck --check-prefix=SECONDFIRST %s
 
 ## Verify matching of archive library names in KEEP.
-# RUN: echo 'SECTIONS{.foo :{ KEEP(*lib2*(.foo)) KEEP(*lib1*(.foo)) }}' > 9.t
+# RUN: echo 'SECTIONS{.foo :{ KEEP(*lib2.a:(.foo)) KEEP(*lib1*(.foo)) }}' > 9.t
 # RUN: ld.lld -o 9 -T 9.t --whole-archive \
 # RUN:   dir1/lib1.a dir2/lib2.a
 # RUN: llvm-objdump -s 9 | FileCheck --check-prefix=SECONDFIRST %s
@@ -72,6 +73,11 @@
 # RUN: ld.lld -o 11 -T 11.t --whole-archive 'lib1().a' dir2/lib2.a
 # RUN: llvm-objdump -s 11 | FileCheck --check-prefix=SECONDFIRST %s
 
+## Verify that matching files excluded from an archive will not match files within one.
+# RUN: echo 'SECTIONS{.foo :{ KEEP(:*x.o(.foo)) KEEP(*y.o(.foo)) KEEP(*x.o(.foo)) }}' > 12.t
+# RUN: ld.lld -o 12 -T 12.t --whole-archive combined.a
+# RUN: llvm-objdump -s 12 | FileCheck --check-prefix=SECONDFIRST %s
+
 #--- tx.s
 .global _start
 _start: