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Differential D63946

[TSan] Improve handling of stack pointer mangling in {set,long}jmp, pt.4
ClosedPublic

Authored by yln on Jun 28 2019, 11:24 AM.

Details

Reviewers
dvyukov
Commits
rCRT365229: [TSan] Improve handling of stack pointer mangling in {set,long}jmp, pt.4
rG6bb13da7c16f: [TSan] Improve handling of stack pointer mangling in {set,long}jmp, pt.4
rL365229: [TSan] Improve handling of stack pointer mangling in {set,long}jmp, pt.4
Summary

Since we don't clobber %rsi (2nd argument) anymore, we don't have to
save/restore it.

Diff Detail

Repository
rL LLVM

Event Timeline

yln created this revision.Jun 28 2019, 11:24 AM
Herald added projects: Restricted Project, Restricted Project. · View Herald TranscriptJun 28 2019, 11:24 AM
Herald added subscribers: llvm-commits, Restricted Project, kubamracek. · View Herald Transcript
Harbormaster completed remote builds in B34083: Diff 207112.Jun 28 2019, 11:30 AM
dvyukov accepted this revision.Jul 4 2019, 11:22 AM

Nice!

This revision is now accepted and ready to land.Jul 4 2019, 11:22 AM
Closed by commit rL365229: [TSan] Improve handling of stack pointer mangling in {set,long}jmp, pt.4 (authored by yln). · Explain WhyJul 5 2019, 11:02 AM
This revision was automatically updated to reflect the committed changes.
Herald added a subscriber: delcypher. · View Herald TranscriptJul 5 2019, 11:02 AM
yln added a comment.Jul 5 2019, 2:10 PM

I reverted this, because we are doing a call (%rsi is not a preserved register), so of course we have to save/restore it (even if we don't clobber it ourselves).

Revision Contents

PathSize
compiler-rt/
trunk/
lib/
tsan/
rtl/
36 lines

Diff 208211

compiler-rt/trunk/lib/tsan/rtl/tsan_rtl_amd64.S

Show First 20 Lines • Show All 265 Lines • ▼ Show 20 Lines
ASM_TYPE_FUNCTION(ASM_SYMBOL_INTERCEPTOR(sigsetjmp)) ASM_TYPE_FUNCTION(ASM_SYMBOL_INTERCEPTOR(sigsetjmp))
ASM_SYMBOL_INTERCEPTOR(sigsetjmp): ASM_SYMBOL_INTERCEPTOR(sigsetjmp):
#endif #endif
CFI_STARTPROC CFI_STARTPROC
// save env parameter // save env parameter
push %rdi push %rdi
CFI_ADJUST_CFA_OFFSET(8) CFI_ADJUST_CFA_OFFSET(8)
CFI_REL_OFFSET(%rdi, 0) CFI_REL_OFFSET(%rdi, 0)
// save savesigs parameter
push %rsi
CFI_ADJUST_CFA_OFFSET(8)
CFI_REL_OFFSET(%rsi, 0)
// align stack frame
sub $8, %rsp
CFI_ADJUST_CFA_OFFSET(8)
// obtain SP, store in %rdi, first argument to `void __tsan_setjmp(uptr sp)` // obtain SP, store in %rdi, first argument to `void __tsan_setjmp(uptr sp)`
#if defined(__FreeBSD__) || defined(__NetBSD__) #if defined(__FreeBSD__) || defined(__NetBSD__)
lea 24(%rsp), %rdi lea 8(%rsp), %rdi
#elif defined(__linux__) || defined(__APPLE__) #elif defined(__linux__) || defined(__APPLE__)
lea 32(%rsp), %rdi lea 16(%rsp), %rdi
#else #else
# error "Unknown platform" # error "Unknown platform"
#endif #endif
// call tsan interceptor // call tsan interceptor
call ASM_SYMBOL(__tsan_setjmp) call ASM_SYMBOL(__tsan_setjmp)
// unalign stack frame
add $8, %rsp
CFI_ADJUST_CFA_OFFSET(-8)
// restore savesigs parameter
pop %rsi
CFI_ADJUST_CFA_OFFSET(-8)
CFI_RESTORE(%rsi)
// restore env parameter // restore env parameter
pop %rdi pop %rdi
CFI_ADJUST_CFA_OFFSET(-8) CFI_ADJUST_CFA_OFFSET(-8)
CFI_RESTORE(%rdi) CFI_RESTORE(%rdi)
// tail jump to libc sigsetjmp // tail jump to libc sigsetjmp
movl $0, %eax movl $0, %eax
#if defined(__NetBSD__) #if defined(__NetBSD__)
movq _ZN14__interception18real___sigsetjmp14E@GOTPCREL(%rip), %rdx movq _ZN14__interception18real___sigsetjmp14E@GOTPCREL(%rip), %rdx
Show All 16 Lines
.globl ASM_SYMBOL_INTERCEPTOR(__sigsetjmp) .globl ASM_SYMBOL_INTERCEPTOR(__sigsetjmp)
ASM_TYPE_FUNCTION(ASM_SYMBOL_INTERCEPTOR(__sigsetjmp)) ASM_TYPE_FUNCTION(ASM_SYMBOL_INTERCEPTOR(__sigsetjmp))
ASM_SYMBOL_INTERCEPTOR(__sigsetjmp): ASM_SYMBOL_INTERCEPTOR(__sigsetjmp):
CFI_STARTPROC CFI_STARTPROC
// save env parameter // save env parameter
push %rdi push %rdi
CFI_ADJUST_CFA_OFFSET(8) CFI_ADJUST_CFA_OFFSET(8)
CFI_REL_OFFSET(%rdi, 0) CFI_REL_OFFSET(%rdi, 0)
// save savesigs parameter
push %rsi
CFI_ADJUST_CFA_OFFSET(8)
CFI_REL_OFFSET(%rsi, 0)
// align stack frame
sub $8, %rsp
CFI_ADJUST_CFA_OFFSET(8)
// obtain SP, store in %rdi, first argument to `void __tsan_setjmp(uptr sp)` // obtain SP, store in %rdi, first argument to `void __tsan_setjmp(uptr sp)`
#if defined(__FreeBSD__) #if defined(__FreeBSD__)
lea 24(%rsp), %rdi lea 8(%rsp), %rdi
#else #else
lea 32(%rsp), %rdi lea 16(%rsp), %rdi
#endif #endif
// call tsan interceptor // call tsan interceptor
call ASM_SYMBOL(__tsan_setjmp) call ASM_SYMBOL(__tsan_setjmp)
// unalign stack frame
add $8, %rsp
CFI_ADJUST_CFA_OFFSET(-8)
// restore savesigs parameter
pop %rsi
CFI_ADJUST_CFA_OFFSET(-8)
CFI_RESTORE(%rsi)
// restore env parameter // restore env parameter
pop %rdi pop %rdi
CFI_ADJUST_CFA_OFFSET(-8) CFI_ADJUST_CFA_OFFSET(-8)
CFI_RESTORE(%rdi) CFI_RESTORE(%rdi)
// tail jump to libc sigsetjmp // tail jump to libc sigsetjmp
movl $0, %eax movl $0, %eax
movq _ZN14__interception16real___sigsetjmpE@GOTPCREL(%rip), %rdx movq _ZN14__interception16real___sigsetjmpE@GOTPCREL(%rip), %rdx
jmp *(%rdx) jmp *(%rdx)
CFI_ENDPROC CFI_ENDPROC
ASM_SIZE(ASM_SYMBOL_INTERCEPTOR(__sigsetjmp)) ASM_SIZE(ASM_SYMBOL_INTERCEPTOR(__sigsetjmp))
#endif // !defined(__APPLE__) && !defined(__NetBSD__) #endif // !defined(__APPLE__) && !defined(__NetBSD__)
NO_EXEC_STACK_DIRECTIVE NO_EXEC_STACK_DIRECTIVE
#endif #endif