[lld] lld: add support for NOCROSSREFS(_TO) (PR #95714)

[Fangrui Song via llvm-commits]

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@@ -0,0 +1,149 @@
+// REQUIRES: x86
+
+// RUN: llvm-mc --triple=x86_64-unknown-linux -filetype=obj -o %t.o %s
+// RUN: echo "NOCROSSREFS(.text .text1); \
+// RUN:       SECTIONS { \
+// RUN:         .text  : { *(.text) } \
+// RUN:         .text1 : { *(.text1) } \
+// RUN:         .text2 : { *(.text2) } \
+// RUN: } " > %t.script
+// RUN: not ld.lld %t.o -o %t --script %t.script 2>&1 | FileCheck -check-prefix=ERR %s
+// ERR: ld.lld: error: {{.*}}.o:(.text+{{.*}}): prohibited cross reference from .text to in .text1
+
+// RUN: llvm-mc --triple=x86_64-unknown-linux -filetype=obj -o %t.o %s
+// RUN: echo "NOCROSSREFS_TO(.text1 .text); \
+// RUN:       SECTIONS { \
+// RUN:         .text  : { *(.text) } \
+// RUN:         .text1 : { *(.text1) } \
+// RUN:         .text2 : { *(.text2) } \
+// RUN: } " > %t.script
+// RUN: not ld.lld %t.o -o %t --script %t.script 2>&1 | FileCheck -check-prefix=ERR1 %s
+// ERR1: ld.lld: error: {{.*}}.o:(.text+{{.*}}): prohibited cross reference from .text to in .text1
+
+// RUN: llvm-mc --triple=x86_64-unknown-linux -filetype=obj -o %t.o %s
+// RUN: echo "NOCROSSREFS(.text1 .text .text2); \
+// RUN:       SECTIONS { \
+// RUN:         .text  : { *(.text) } \
+// RUN:         .text1 : { *(.text1) } \
+// RUN:         .text2 : { *(.text2) } \
+// RUN: } " > %t.script
+// RUN: not ld.lld %t.o -o %t --script %t.script 2>&1 | FileCheck -check-prefix=ERR2 %s
+// ERR2: ld.lld: error: {{.*}}.o:(.text+{{.*}}): prohibited cross reference from .text to in .text1
+
+// RUN: llvm-mc --triple=x86_64-unknown-linux -filetype=obj -o %t.o %s
+// RUN: echo "NOCROSSREFS_TO(.text .text1); \
+// RUN:       SECTIONS { \
+// RUN:         .text  : { *(.text) } \
+// RUN:         .text1 : { *(.text1) } \
+// RUN:         .text2 : { *(.text2) } \
+// RUN: } " > %t.script
+// RUN: ld.lld %t.o -o %t --script %t.script 2>&1
+
+// RUN: llvm-mc --triple=x86_64-unknown-linux -filetype=obj -o %t.o %s
+// RUN: echo "NOCROSSREFS_TO(); \
+// RUN:       SECTIONS { \
+// RUN:         .text  : { *(.text) } \
+// RUN:         .text1 : { *(.text1) } \
+// RUN:         .text2 : { *(.text2) } \
+// RUN: } " > %t.script
+// RUN: ld.lld %t.o -o %t --script %t.script 2>&1
+
+// RUN: llvm-mc --triple=x86_64-unknown-linux -filetype=obj -o %t.o %s
+// RUN: echo "NOCROSSREFS(); \
+// RUN:       SECTIONS { \
+// RUN:         .text  : { *(.text) } \
+// RUN:         .text1 : { *(.text1) } \
+// RUN:         .text2 : { *(.text2) } \
+// RUN: } " > %t.script
+// RUN: ld.lld %t.o -o %t --script %t.script 2>&1
+
+// RUN: llvm-mc --triple=x86_64-unknown-linux -filetype=obj -o %t.o %s
+// RUN: echo "NOCROSSREFS(.text); \
+// RUN:       SECTIONS { \
+// RUN:         .text  : { *(.text) } \
+// RUN:         .text1 : { *(.text1) } \
+// RUN:         .text2 : { *(.text2) } \
+// RUN: } " > %t.script
+// RUN: ld.lld %t.o -o %t --script %t.script 2>&1
+
+// RUN: llvm-mc --triple=x86_64-unknown-linux -filetype=obj -o %t.o %s
+// RUN: echo "NOCROSSREFS_TO(.text); \
+// RUN:       SECTIONS { \
+// RUN:         .text  : { *(.text) } \
+// RUN:         .text1 : { *(.text1) } \
+// RUN:         .text2 : { *(.text2) } \
+// RUN: } " > %t.script
+// RUN: ld.lld %t.o -o %t --script %t.script 2>&1
+
+// RUN: llvm-mc --triple=x86_64-unknown-linux -filetype=obj -o %t.o %s
+// RUN: echo "NOCROSSREFS_TO(.text2 .text); \
+// RUN:       SECTIONS { \
+// RUN:         .text  : { *(.text) } \
+// RUN:         .text1 : { *(.text1) } \
+// RUN:         .text2 : { *(.text2) } \
+// RUN: } " > %t.script
+// RUN: ld.lld %t.o -o %t --script %t.script 2>&1
+
+// RUN: llvm-mc --triple=x86_64-unknown-linux -filetype=obj -o %t.o %s
+// RUN: echo "NOCROSSREFS(.text .text2); \
+// RUN:       SECTIONS { \
+// RUN:         .text  : { *(.text) } \
+// RUN:         .text1 : { *(.text1) } \
+// RUN:         .text2 : { *(.text2) } \
+// RUN: } " > %t.script
+// RUN: ld.lld %t.o -o %t --script %t.script 2>&1
+
+// RUN: llvm-mc --triple=x86_64-unknown-linux -filetype=obj -o %t.o %s
+// RUN: echo "NOCROSSREFS(.text .text2); \
+// RUN:       SECTIONS { \
+// RUN:          foo = ABSOLUTE(.); \
+// RUN:         .text  : { *(.text) } \
+// RUN:         .text1 : { *(.text1) } \
+// RUN:         .text2 : { *(.text2) } \
+// RUN: } " > %t.script
+// RUN: ld.lld %t.o -o %t --script %t.script 2>&1
+
+// RUN: llvm-mc --triple=x86_64-unknown-linux -filetype=obj -o %t.o %s
+// RUN: echo "NOCROSSREFS(.text .text2); \
+// RUN:       SECTIONS { \
+// RUN:         .text  : { *(.text) } \
+// RUN:         .text1 : { *(.text1) } \
+// RUN:         .text2 : { *(.text2) } \
+// RUN:         .bss   : { *(.unused) } \
+// RUN: } " > %t.script
+// RUN: ld.lld %t.o -o %t --script %t.script 2>&1
+
+// RUN: llvm-mc --triple=x86_64-unknown-linux -filetype=obj -o %t.o %s
+// RUN: echo "NOCROSSREFS(.text .bss); \
+// RUN:       SECTIONS { \
+// RUN:         .text  : { *(.text) } \
+// RUN:         .text1 : { *(.text1) } \
+// RUN:         .text2 : { *(.text2) } \
+// RUN:         .bss   : { *(.unused) } \
+// RUN: } " > %t.script
+// RUN: not ld.lld %t.o -o %t --script %t.script 2>&1 | FileCheck -check-prefix=ERR3 %s
+// ERR3: ld.lld: error: {{.*}}.o:(.text+{{.*}}): prohibited cross reference from .text to unused in .bss
----------------
MaskRay wrote:

Omit `ld.lld: `. We don't test the string (which might change) before `error:`

If you use the `# RUN: rm -rf %t && split-file %s %t && cd %t` pattern, which is popular in new tests, you can replace `{{.*}}` with the exact name. 
The section offset is important. Don't omit it.

https://github.com/llvm/llvm-project/pull/95714