[ELF, LinkerScript] Support ! operator in linker script.

[abidh]

Summary

This small patch adds the support for ! operator in linker scripts.

[grimar]

test/ELF/linkerscript/assert.s

46

You can reuse FAIL I think.

# RUN: FileCheck %s -check-prefix=FAIL < %t.log

53

Excessive empty line.

test/ELF/linkerscript/symbol-assignexpr.s

18

All your new testcases using parentheses, is there some problem without them ?

[meadori]

Outside the comments @grimar made, LGTM.

[abidh]

Handle review comments.

[abidh]

test/ELF/linkerscript/assert.s

46

I tried but it was not immediately obvious how to do it.

test/ELF/linkerscript/symbol-assignexpr.s

18

The linker script parsing have problem where it can not separate these operator. You will see that test of ~ operator also use '(' or space in between. I have also changed one test to use space but this needs to be fixed as a separate problem.

[grimar]

test/ELF/linkerscript/assert.s

46

Following just works, no ?

# RUN: echo "SECTIONS { ASSERT(!(1), fail) }" > %t9.script
# RUN: not ld.lld -shared -o %t9 --script %t9.script %t1.o > %t.log 2>&1
# RUN: FileCheck %s -check-prefix=FAIL < %t.log

test/ELF/linkerscript/symbol-assignexpr.s

18

I fixed '~' here: D36508, I think you should be able to do the same for '!`

[ruiu]

test/ELF/linkerscript/assert.s

1

I wouldn't add any tests to this file as the feature is tested by symbol-assignexpr.s.

48–52

I wouldn't add this test -- the feature is tested enough with the above two tests.

test/ELF/linkerscript/symbol-assignexpr.s

18

Replace !symbol with !1 and add symbol14 = !0.

[ruiu]

ELF/ScriptLexer.cpp

215–217 ↗

(On Diff #110390)

I don't think this is correct. For example, I don't think this can handle expression 0!=1. You want to add code to tokenizeExpr instead of this function.

[abidh]

Fix case pointed out in review comments.

[abidh]

ELF/ScriptLexer.cpp

215–217 ↗

(On Diff #110390)

I think 0!=1 was failing even without my patch. I have fixed it now and added a test to check it.

[ruiu]

LGTM

ELF/ScriptLexer.cpp

193–197 ↗

(On Diff #110532)

This is probably a bit more straightforward:

if (S.substr(E).startswith("!=")) {
  Ret.push_back(S.substr(E, 2));
  S = S.substr(E + 2);
} else {
  Ret.push_back(S.substr(E, 1));
  S = S.substr(E + 1);
}

test/ELF/linkerscript/symbol-assignexpr.s

20

Thank you for adding this test.

ELF/ScriptParser.cpp

 Expr ScriptParser::readPrimary() {
   if (peek() == "(")
     return readParenExpr();
 
   if (consume("~")) {
     Expr E = readPrimary();
     return [=] { return ~E().getValue(); };
   }
+  if (consume("!")) {
+    Expr E = readPrimary();
+    return [=] { return !E().getValue(); };
+  }
   if (consume("-")) {
     Expr E = readPrimary();
     return [=] { return -E().getValue(); };
   }
 
   StringRef Tok = next();
   std::string Location = getCurrentLocation();
 

test/ELF/linkerscript/assert.s

 # REQUIRES: x86
 # RUN: llvm-mc -filetype=obj -triple=x86_64-unknown-linux %s -o %t1.o
 
 # RUN: echo "SECTIONS { ASSERT(1, fail) }" > %t1.script
 # RUN: ld.lld -shared -o %t1 --script %t1.script %t1.o
 # RUN: llvm-readobj %t1 > /dev/null
 
 # RUN: echo "SECTIONS { ASSERT(0, fail) }" > %t3.script
 # RUN: not ld.lld -shared -o %t3 --script %t3.script %t1.o > %t.log 2>&1

 # RUN: ld.lld -shared -o %t6 --script %t6.script %t1.o
 # RUN: llvm-readobj %t6 > /dev/null
 
 # RUN: echo "SECTIONS { .foo : { ASSERT(1, \"true\") } }" > %t7.script
 # RUN: not ld.lld -shared -o %t7 --script %t7.script %t1.o > %t.log 2>&1
 # RUN: FileCheck %s -check-prefix=CHECK-SEMI < %t.log
 # CHECK-SEMI: error: {{.*}}.script:1: ; expected, but got }
 
+## Test assert with ! operator
+# RUN: echo "SECTIONS { ASSERT(!(0), fail) }" > %t8.script
+# RUN: ld.lld -shared -o %t8 --script %t8.script %t1.o
+# RUN: llvm-readobj %t8 > /dev/null
+
+# RUN: echo "SECTIONS { ASSERT(!(1), fail) }" > %t9.script
+# RUN: not ld.lld -shared -o %t9 --script %t9.script %t1.o > %t.log 2>&1
+# RUN: FileCheck %s -check-prefix=FAIL1 < %t.log
+# FAIL1: fail
+
+# RUN: echo "SECTIONS { .foo : { *(.foo) } }" > %t10.script
+# RUN: echo "ASSERT(!(SIZEOF(.foo) == 0), fail);" >> %t10.script
+# RUN: ld.lld -shared -o %t10 --script %t10.script %t1.o
+# RUN: llvm-readobj %t10 > /dev/null
+
 .section .foo, "a"
  .quad 0

test/ELF/linkerscript/symbol-assignexpr.s

 # RUN:         symbol6 = symbol - ~(0xfff0 + 0xb); \
 # RUN:         symbol7 = symbol - ~ 0xfffb + 4; \
 # RUN:         symbol8 = ~ 0xffff + 4; \
 # RUN:         symbol9 = - 4; \
 # RUN:         symbol10 = 0xfedcba9876543210; \
 # RUN:         symbol11 = ((0x28000 + 0x1fff) & ~(0x1000 + -1)); \
 # RUN:         symbol12 = 0x1234; \
 # RUN:         symbol12 += 1; \
+# RUN:         symbol13 = ! symbol; \
 # RUN:         bar = 0x5678; \
 # RUN:         baz = 0x9abc; \
 # RUN:       }" > %t.script
 # RUN: ld.lld -o %t1 --script %t.script %t
 # RUN: llvm-objdump -t %t1 | FileCheck %s
 
 # CHECK:      SYMBOL TABLE:
 # CHECK-NEXT: 0000000000000000 *UND* 00000000
 # CHECK-NEXT: 0000000000000000 .text 00000000 _start
 # CHECK-NEXT: 0000000000005678 *ABS* 00000000 bar
 # CHECK-NEXT: 0000000000009abc *ABS* 00000000 baz
 # CHECK-NEXT: 0000000000000001 .text 00000000 foo
 # CHECK-NEXT: 0000000000001000 *ABS* 00000000 symbol
 # CHECK-NEXT: 0000000000002234 *ABS* 00000000 symbol2
 # CHECK-NEXT: 0000000000002234 *ABS* 00000000 symbol3
 # CHECK-NEXT: 0000000000000ffc *ABS* 00000000 symbol4
 # CHECK-NEXT: 0000000000010ffc *ABS* 00000000 symbol5
 # CHECK-NEXT: 0000000000010ffc *ABS* 00000000 symbol6
 # CHECK-NEXT: 0000000000011000 *ABS* 00000000 symbol7
 # CHECK-NEXT: ffffffffffff0004 *ABS* 00000000 symbol8
 # CHECK-NEXT: fffffffffffffffc *ABS* 00000000 symbol9
 # CHECK-NEXT: fedcba9876543210 *ABS* 00000000 symbol10
 # CHECK-NEXT: 0000000000029000 *ABS* 00000000 symbol11
 # CHECK-NEXT: 0000000000001235 *ABS* 00000000 symbol12
+# CHECK-NEXT: 0000000000000000 *ABS* 00000000 symbol13
 
 # RUN: echo "SECTIONS { symbol2 = symbol; }" > %t2.script
 # RUN: not ld.lld -o %t2 --script %t2.script %t 2>&1 \
 # RUN:  | FileCheck -check-prefix=ERR %s
 # ERR: {{.*}}.script:1: symbol not found: symbol
 
 .global _start
 _start: