gfids-icf.s 2.74 KB
# REQUIRES: x86
# RUN: llvm-mc -triple x86_64-windows-msvc %s -filetype=obj -o %t.obj
# RUN: lld-link %t.obj -guard:nolongjmp -out:%t.exe -opt:icf -entry:main
# RUN: llvm-readobj --file-headers --coff-load-config %t.exe | FileCheck %s --check-prefix=CHECK

# This assembly is meant to mimic what CL emits for this kind of C code:
# int icf1() { return 42; }
# int icf2() { return 42; }
# int (*fp1)() = &icf1;
# int (*fp2)() = &icf2;
# int main() {
#   return fp1();
#   return fp2();
# }

# 'icf1' and 'icf2' are address taken, but should be merged into one entry.
# There are two entries in the table because 'main' is included.

# CHECK: ImageBase: 0x140000000
# CHECK: LoadConfig [
# CHECK:   SEHandlerTable: 0x0
# CHECK:   SEHandlerCount: 0
# CHECK:   GuardCFCheckFunction: 0x0
# CHECK:   GuardCFCheckDispatch: 0x0
# CHECK:   GuardCFFunctionTable: 0x14000{{.*}}
# CHECK:   GuardCFFunctionCount: 2
# CHECK:   GuardFlags: 0x500
# CHECK:   GuardAddressTakenIatEntryTable: 0x0
# CHECK:   GuardAddressTakenIatEntryCount: 0
# CHECK:   GuardLongJumpTargetTable: 0x0
# CHECK:   GuardLongJumpTargetCount: 0
# CHECK: ]
# CHECK:      GuardFidTable [
# CHECK-NEXT:   0x14000{{.*}}
# CHECK-NEXT:   0x14000{{.*}}
# CHECK-NEXT: ]

# There should be no .gfids section in the output exectuable when we link with
# -guard:cf or with no -guard:cf/nolongjmp flag.
# RUN: llvm-readobj --sections %t.exe | FileCheck %s --check-prefix NOGFIDSEC
# RUN: lld-link %t.obj -out:%t.exe -opt:icf -entry:main
# RUN: llvm-readobj --sections %t.exe | FileCheck %s --check-prefix NOGFIDSEC

# NOGFIDSEC: Sections [
# NOGFIDSEC: Section {
# NOGFIDSEC: Name: .text
# NOGFIDSEC-NOT: Name: .gfids

# Indicate that gfids are present.
        .def     @feat.00; .scl    3; .type   0; .endef
        .globl  @feat.00
@feat.00 = 0x800

        .def     icf1; .scl    2; .type   32; .endef
        .section        .text,"xr",one_only,icf1
        .global icf1
icf1:
        movl $42, %eax
        retq

        .def     icf2; .scl    2; .type   32; .endef
        .section        .text,"xr",one_only,icf2
        .global icf2
icf2:
        movl $42, %eax
        retq

# Take their two addresses.
        .data
        .globl  fp1
fp1:
        .quad   icf1
        .globl  fp2
fp2:
        .quad   icf2

        .section        .gfids$y,"dr"
        .symidx icf1
        .symidx icf2

        .def     main; .scl    2; .type   32; .endef
        .section        .text,"xr",one_only,main
        .globl  main
main:
        callq      *fp1(%rip)
        callq      *fp2(%rip)
        xor %eax, %eax
        retq

        .section .rdata,"dr"
.globl _load_config_used
_load_config_used:
        .long 256
        .fill 124, 1, 0
        .quad __guard_fids_table
        .quad __guard_fids_count
        .long __guard_flags
        .fill 128, 1, 0