LinkerScript: Add parsing of the EXTERN command

This patch implements parsing of the GNU ld EXTERN command [1].
Evaluation will be added at a later point in time.

[1] https://sourceware.org/binutils/docs/ld/Miscellaneous-Commands.html#Miscellaneous-Commands

llvm-svn: 232110

3 files changed, 70 insertions, 0 deletions

diff --git a/lld/test/LinkerScript/extern-bad-symbol.test b/lld/test/LinkerScript/extern-bad-symbol.test
new file mode 100644
index 00000000000..279a7cc2056
--- /dev/null
+++ b/lld/test/LinkerScript/extern-bad-symbol.test
@@ -0,0 +1,22 @@
+/*
+  RUN: linker-script-test %s 2> %t | FileCheck %s
+  RUN: FileCheck -input-file %t -check-prefix=CHECK-ERR %s
+*/
+
+
+EXTERN(a b 3)
+/*
+CHECK-ERR: [[@LINE-2]]:12: error: expected symbol in EXTERN.
+CHECK-ERR-NEXT: {{^EXTERN\(a b 3\)}}
+CHECK-ERR-NEXT: {{^          \^}}
+*/
+
+/*
+CHECK: kw_extern: EXTERN
+CHECK: l_paren: (
+CHECK: identifier: a
+CHECK: identifier: b
+CHECK: number: 3
+CHECK: r_paren: )
+CHECK: eof:
+*/
diff --git a/lld/test/LinkerScript/extern-empty.test b/lld/test/LinkerScript/extern-empty.test
new file mode 100644
index 00000000000..a5e1ece084d
--- /dev/null
+++ b/lld/test/LinkerScript/extern-empty.test
@@ -0,0 +1,19 @@
+/*
+  RUN: linker-script-test %s 2> %t | FileCheck %s
+  RUN: FileCheck -input-file %t -check-prefix=CHECK-ERR %s
+*/
+
+
+EXTERN()
+/*
+CHECK-ERR: [[@LINE-2]]:8: error: expected one or more symbols in EXTERN.
+CHECK-ERR-NEXT: {{^EXTERN()}}
+CHECK-ERR-NEXT: {{^     \^}}
+*/
+
+/*
+CHECK: kw_extern: EXTERN
+CHECK: l_paren: (
+CHECK: r_paren: )
+CHECK: eof:
+*/
diff --git a/lld/test/LinkerScript/extern-valid.test b/lld/test/LinkerScript/extern-valid.test
new file mode 100644
index 00000000000..764b4668a34
--- /dev/null
+++ b/lld/test/LinkerScript/extern-valid.test
@@ -0,0 +1,29 @@
+/*
+  RUN: linker-script-test %s | FileCheck %s
+*/
+
+EXTERN(a)
+EXTERN(a b)
+EXTERN(_foo _bar _baz)
+
+/*
+CHECK: kw_extern: EXTERN
+CHECK: l_paren: (
+CHECK: identifier: a
+CHECK: r_paren: )
+CHECK: kw_extern: EXTERN
+CHECK: l_paren: (
+CHECK: identifier: a
+CHECK: identifier: b
+CHECK: r_paren: )
+CHECK: kw_extern: EXTERN
+CHECK: l_paren: (
+CHECK: identifier: _foo
+CHECK: identifier: _bar
+CHECK: identifier: _baz
+CHECK: r_paren: )
+CHECK: eof:
+CHECK: EXTERN(a)
+CHECK: EXTERN(a b)
+CHECK: EXTERN(_foo _bar _baz)
+*/