llvm-project/lld/test/COFF/comdat-selection-associativ...

# REQUIRES: x86

# Tests handling of several comdats with "largest" selection type that each
# has an associative comdat.

# Create obj files.
# RUN: sed -e s/TYPE/.byte/  -e s/SIZE/1/ %s | llvm-mc -triple x86_64-pc-win32 -filetype=obj -o %t.1.obj
# RUN: sed -e s/TYPE/.short/ -e s/SIZE/2/ %s | llvm-mc -triple x86_64-pc-win32 -filetype=obj -o %t.2.obj
# RUN: sed -e s/TYPE/.long/  -e s/SIZE/4/ %s | llvm-mc -triple x86_64-pc-win32 -filetype=obj -o %t.4.obj

        .section .text$ac, "", associative, symbol
assocsym:
        .long SIZE

        .section .text$nm, "", largest, symbol
        .globl symbol
symbol:
        TYPE SIZE

# Pass the obj files in different orders and check that only the associative
# comdat of the largest obj file makes it into the output, independent of
# the order of the obj files on the command line.

# FIXME: Make these pass when /opt:noref is passed.

# RUN: lld-link /include:symbol /dll /noentry /nodefaultlib %t.1.obj %t.2.obj %t.4.obj /out:%t.exe
# RUN: llvm-objdump -s %t.exe | FileCheck --check-prefix=ALL124 %s
# ALL124: Contents of section .text:
# ALL124:   180001000 04000000 04000000 ....

# RUN: lld-link /include:symbol /dll /noentry /nodefaultlib %t.4.obj %t.2.obj %t.1.obj /out:%t.exe
# RUN: llvm-objdump -s %t.exe | FileCheck --check-prefix=ALL421 %s
# ALL421: Contents of section .text:
# ALL421:   180001000 04000000 04000000 ....

# RUN: lld-link /include:symbol /dll /noentry /nodefaultlib %t.2.obj %t.4.obj %t.1.obj /out:%t.exe
# RUN: llvm-objdump -s %t.exe | FileCheck --check-prefix=ALL241 %s
# ALL241: Contents of section .text:
# ALL241:   180001000 04000000 04000000 ....

# RUN: lld-link /include:symbol /dll /noentry /nodefaultlib %t.2.obj %t.1.obj /out:%t.exe
# RUN: llvm-objdump -s %t.exe | FileCheck --check-prefix=JUST21 %s
# JUST21: Contents of section .text:
# JUST21:   180001000 02000000 0200 ....
lld/coff: Implement some support for the comdat selection field LLD used to handle comdats as if the selection field was always set to IMAGE_COMDAT_SELECT_ANY. This means for obj files produced by `cl /Gy`, LLD would never report a duplicate symbol error. This change: - adds validation for the Selection field (should make no difference in practice for compiler-generated obj inputs) - rejects comdats that have different Selection fields in different obj files (likewise). This is a bit more strict but also more self-consistent thank link.exe (see comment in code) - implements handling for all the selection kinds In practice, compilers only generate comdats with IMAGE_COMDAT_SELECT_NODUPLICATES (LLD now produces duplicate symbol errors for these), IMAGE_COMDAT_SELECT_ANY (no behavior change), and IMAGE_COMDAT_SELECT_LARGEST (for RTTI data; here LLD should no longer create broken executables when linking some TUs with RTTI enabled and some with it disabled – but see below). The implementation of `IMAGE_COMDAT_SELECT_LARGEST` is incomplete: If one SELECT_LARGEST comdat replaces an earlier one, the comdat symbol is replaced correctly, but the old section stays loaded and if /opt:ref is disabled (via /opt:noref or /debug) it's still written to the output. That's not ideal, but better than the current treatment of just picking any one of those comdats. I hope to fix this better later. Fixes most of PR40094. Differential Revision: https://reviews.llvm.org/D57324 llvm-svn: 352590 2019-01-30 10:17:27 +08:00			`# REQUIRES: x86`

			`# Tests handling of several comdats with "largest" selection type that each`
			`# has an associative comdat.`

			`# Create obj files.`
			`# RUN: sed -e s/TYPE/.byte/ -e s/SIZE/1/ %s \| llvm-mc -triple x86_64-pc-win32 -filetype=obj -o %t.1.obj`
			`# RUN: sed -e s/TYPE/.short/ -e s/SIZE/2/ %s \| llvm-mc -triple x86_64-pc-win32 -filetype=obj -o %t.2.obj`
			`# RUN: sed -e s/TYPE/.long/ -e s/SIZE/4/ %s \| llvm-mc -triple x86_64-pc-win32 -filetype=obj -o %t.4.obj`

			`.section .text$ac, "", associative, symbol`
			`assocsym:`
			`.long SIZE`

			`.section .text$nm, "", largest, symbol`
			`.globl symbol`
			`symbol:`
			`TYPE SIZE`

			`# Pass the obj files in different orders and check that only the associative`
			`# comdat of the largest obj file makes it into the output, independent of`
			`# the order of the obj files on the command line.`

			`# FIXME: Make these pass when /opt:noref is passed.`

			`# RUN: lld-link /include:symbol /dll /noentry /nodefaultlib %t.1.obj %t.2.obj %t.4.obj /out:%t.exe`
			`# RUN: llvm-objdump -s %t.exe \| FileCheck --check-prefix=ALL124 %s`
			`# ALL124: Contents of section .text:`
			`# ALL124: 180001000 04000000 04000000 ....`

			`# RUN: lld-link /include:symbol /dll /noentry /nodefaultlib %t.4.obj %t.2.obj %t.1.obj /out:%t.exe`
			`# RUN: llvm-objdump -s %t.exe \| FileCheck --check-prefix=ALL421 %s`
			`# ALL421: Contents of section .text:`
			`# ALL421: 180001000 04000000 04000000 ....`

			`# RUN: lld-link /include:symbol /dll /noentry /nodefaultlib %t.2.obj %t.4.obj %t.1.obj /out:%t.exe`
			`# RUN: llvm-objdump -s %t.exe \| FileCheck --check-prefix=ALL241 %s`
			`# ALL241: Contents of section .text:`
			`# ALL241: 180001000 04000000 04000000 ....`

			`# RUN: lld-link /include:symbol /dll /noentry /nodefaultlib %t.2.obj %t.1.obj /out:%t.exe`
			`# RUN: llvm-objdump -s %t.exe \| FileCheck --check-prefix=JUST21 %s`
			`# JUST21: Contents of section .text:`
			`# JUST21: 180001000 02000000 0200 ....`