[lld] r365635 - [LLD][ELF] - Linkerscript: fix FILL() expressions handling.

[George Rimar via llvm-commits]

Author: grimar
Date: Wed Jul 10 07:36:48 2019
New Revision: 365635

URL: http://llvm.org/viewvc/llvm-project?rev=365635&view=rev
Log:
[LLD][ELF] - Linkerscript: fix FILL() expressions handling.

D64130 introduced a bug described in the following message:
https://reviews.llvm.org/D64130#1571560

The problem can happen with the following script:

SECTIONS {
  .out : {
...
   FILL(0x10101010)
   *(.aaa)
...
}

The current code tries to read (0x10101010) as an expression and
does not break when meets *, what results in a script parsing error.

In this patch, I verify that FILL command's expression always wrapped in ().
And at the same time =<fillexp> expression can be both wrapped or unwrapped.
I checked it matches to bfd/gold.

Differential revision: https://reviews.llvm.org/D64476

Modified:
    lld/trunk/ELF/ScriptParser.cpp
    lld/trunk/test/ELF/linkerscript/fill.test
    lld/trunk/test/ELF/linkerscript/sections-padding.s

Modified: lld/trunk/ELF/ScriptParser.cpp
URL: http://llvm.org/viewvc/llvm-project/lld/trunk/ELF/ScriptParser.cpp?rev=365635&r1=365634&r2=365635&view=diff
==============================================================================
--- lld/trunk/ELF/ScriptParser.cpp (original)
+++ lld/trunk/ELF/ScriptParser.cpp Wed Jul 10 07:36:48 2019
@@ -828,7 +828,9 @@ OutputSection *ScriptParser::readOutputS
       // We handle the FILL command as an alias for =fillexp section attribute,
       // which is different from what GNU linkers do.
       // https://sourceware.org/binutils/docs/ld/Output-Section-Data.html
+      expect("(");
       cmd->filler = readFill();
+      expect(")");
     } else if (tok == "SORT") {
       readSort();
     } else if (tok == "INCLUDE") {

Modified: lld/trunk/test/ELF/linkerscript/fill.test
URL: http://llvm.org/viewvc/llvm-project/lld/trunk/test/ELF/linkerscript/fill.test?rev=365635&r1=365634&r2=365635&view=diff
==============================================================================
--- lld/trunk/test/ELF/linkerscript/fill.test (original)
+++ lld/trunk/test/ELF/linkerscript/fill.test Wed Jul 10 07:36:48 2019
@@ -7,6 +7,7 @@ SECTIONS {
   .out : {
    FILL(0x11111111)
    . += 2;
+   FILL(0x10101010)
    *(.aaa)
    . += 4;
    *(.bbb)
@@ -18,3 +19,7 @@ SECTIONS {
 
 # CHECK:      Contents of section .out:
 # CHECK-NEXT: 2222aa22 222222bb 22222222 22222222
+
+# RUN: echo 'SECTIONS { .out : { FILL 0x11111111 } }' > %t.script
+# RUN: not ld.lld -o /dev/null --script %t.script 2>&1 | FileCheck %s --check-prefix=ERR
+# ERR: ( expected, but got 0x11111111

Modified: lld/trunk/test/ELF/linkerscript/sections-padding.s
URL: http://llvm.org/viewvc/llvm-project/lld/trunk/test/ELF/linkerscript/sections-padding.s?rev=365635&r1=365634&r2=365635&view=diff
==============================================================================
--- lld/trunk/test/ELF/linkerscript/sections-padding.s (original)
+++ lld/trunk/test/ELF/linkerscript/sections-padding.s Wed Jul 10 07:36:48 2019
@@ -7,11 +7,16 @@
 # RUN: llvm-objdump -s %t.out | FileCheck -check-prefix=YES %s
 # YES: 66000011 22000011 22000011 22000011
 
+# RUN: echo "SECTIONS { .mysec : { *(.mysec*) } =0x1100+0x22 }" > %t.script
+# RUN: ld.lld -o %t.out --script %t.script %t
+# RUN: llvm-objdump -s %t.out | FileCheck -check-prefix=YES2 %s
+# YES2: 66000011 22000011 22000011 22000011
+
 ## Confirming that address was correct:
 # RUN: echo "SECTIONS { .mysec : { *(.mysec*) } =0x99887766 }" > %t.script
 # RUN: ld.lld -o %t.out --script %t.script %t
-# RUN: llvm-objdump -s %t.out | FileCheck -check-prefix=YES2 %s
-# YES2: 66998877 66998877 66998877 66998877
+# RUN: llvm-objdump -s %t.out | FileCheck -check-prefix=YES3 %s
+# YES3: 66998877 66998877 66998877 66998877
 
 ## Default padding value is 0x00:
 # RUN: echo "SECTIONS { .mysec : { *(.mysec*) } }" > %t.script
@@ -51,7 +56,7 @@
 # RUN: ld.lld -o %t.out --script %t.script %t
 # RUN: llvm-objdump -s %t.out | FileCheck -check-prefix=YES %s
 
-## Check we report an error if expression value is larger that 32-bits.
+## Check we report an error if expression value is larger than 32-bits.
 # RUN: echo "SECTIONS { .mysec : { *(.mysec*) } =(0x11 << 32) }" > %t.script
 # RUN: not ld.lld -o %t.out --script %t.script %t 2>&1 | FileCheck --check-prefix=ERR3 %s
 # ERR3: filler expression result does not fit 32-bit: 0x1100000000