[ELF] Align the value if needed when computing the expression

Also add the test cases for the addition and subtraction both for
the relative and absolute case.

Differential Revision: https://reviews.llvm.org/D35346

llvm-svn: 308692

3 files changed, 31 insertions, 2 deletions

diff --git a/lld/ELF/ScriptParser.cpp b/lld/ELF/ScriptParser.cpp
index 531c61e6cb4..29570c80d2f 100644
--- a/lld/ELF/ScriptParser.cpp
+++ b/lld/ELF/ScriptParser.cpp
@@ -139,11 +139,13 @@ static void moveAbsRight(ExprValue &A, ExprValue &B) {
 
 static ExprValue add(ExprValue A, ExprValue B) {
   moveAbsRight(A, B);
-  return {A.Sec, A.ForceAbsolute, A.Val + B.getValue(), A.Loc};
+  uint64_t Val = alignTo(A.Val, A.Alignment) + B.getValue();
+  return {A.Sec, A.ForceAbsolute, Val, A.Loc};
 }
 
 static ExprValue sub(ExprValue A, ExprValue B) {
-  return {A.Sec, A.Val - B.getValue(), A.Loc};
+  uint64_t Val = alignTo(A.Val, A.Alignment) - B.getValue();
+  return {A.Sec, Val, A.Loc};
 }
 
 static ExprValue mul(ExprValue A, ExprValue B) {
diff --git a/lld/test/ELF/linkerscript/Inputs/symbol-reserved.script b/lld/test/ELF/linkerscript/Inputs/symbol-reserved.script
new file mode 100644
index 00000000000..269bb120de9
--- /dev/null
+++ b/lld/test/ELF/linkerscript/Inputs/symbol-reserved.script
@@ -0,0 +1,5 @@
+SECTIONS
+{
+  .text : { *(.text) }
+  PROVIDE_HIDDEN(_end = .);
+}
diff --git a/lld/test/ELF/linkerscript/symbol-reserved.s b/lld/test/ELF/linkerscript/symbol-reserved.s
index e0b25959738..23f164e94d0 100644
--- a/lld/test/ELF/linkerscript/symbol-reserved.s
+++ b/lld/test/ELF/linkerscript/symbol-reserved.s
@@ -17,6 +17,28 @@
 
 # ALIGNED: 0000000000200005 .text 00000000 .hidden newsym
 
+# RUN: echo "PROVIDE_HIDDEN(newsym = ALIGN(3, 8) + 10);" > %t.script
+# RUN: ld.lld -o %t1 %t.script %t
+# RUN: llvm-objdump -t %t1 | FileCheck --check-prefix=ALIGN-ADD %s
+# ALIGN-ADD: 0000000000000012 *ABS* 00000000 .hidden newsym
+
+# RUN: echo "PROVIDE_HIDDEN(newsym = ALIGN(11, 8) - 10);" > %t.script
+# RUN: ld.lld -o %t1 %t.script %t
+# RUN: llvm-objdump -t %t1 | FileCheck --check-prefix=ALIGN-SUB %s
+# ALIGN-SUB: 0000000000000006 *ABS* 00000000 .hidden newsym
+
+# RUN: echo "PROVIDE_HIDDEN(newsym = ALIGN(_end, CONSTANT(MAXPAGESIZE)) + 5);" > %t.script
+# RUN: ld.lld -o %t1 --script %p/Inputs/symbol-reserved.script %t %t.script
+# RUN: llvm-objdump -t %t1 | FileCheck --check-prefix=RELATIVE-ADD %s
+# RELATIVE-ADD: 0000000000001005 .text 00000000 .hidden newsym
+# RELATIVE-ADD: 0000000000000007 .text 00000000 .hidden _end
+
+# RUN: echo "PROVIDE_HIDDEN(newsym = ALIGN(_end, CONSTANT(MAXPAGESIZE)) - 5);" > %t.script
+# RUN: ld.lld -o %t1 --script %p/Inputs/symbol-reserved.script %t %t.script
+# RUN: llvm-objdump -t %t1 | FileCheck --check-prefix=RELATIVE-SUB %s
+# RELATIVE-SUB: 0000000000000ffb .text 00000000 .hidden newsym
+# RELATIVE-SUB: 0000000000000007 .text 00000000 .hidden _end
+
 .global _start
 _start:
   lea newsym(%rip),%rax