diff options
Diffstat (limited to 'winsup/cygwin/exceptions.cc')
| -rw-r--r-- | winsup/cygwin/exceptions.cc | 69 |
1 files changed, 47 insertions, 22 deletions
diff --git a/winsup/cygwin/exceptions.cc b/winsup/cygwin/exceptions.cc index fb59c6142..8d341799e 100644 --- a/winsup/cygwin/exceptions.cc +++ b/winsup/cygwin/exceptions.cc @@ -1594,29 +1594,49 @@ _cygtls::call_signal_handler () If the current code does not work as expected in the "usual" POSIX circumstances, this problem must be revisited. */ - /* Compute new stackbase. We start from the high address, subtract - 16 bytes (safe/sorry) and align to 16 byte. */ + /* Compute new stackbase. We start from the high address, aligned + to 16 byte. */ uintptr_t new_sp = (uintptr_t) _my_tls.altstack.ss_sp - + _my_tls.altstack.ss_size - 0x10; + + _my_tls.altstack.ss_size; new_sp &= ~0xf; /* Mark alternate stack as used. */ _my_tls.altstack.ss_flags = SS_ONSTACK; - /* Move to alternate stack, call thisfunc, revert stack regs. */ + /* In assembler: Save regs on new stack, move to alternate stack, + call thisfunc, revert stack regs. */ #ifdef __x86_64__ + /* Clobbered regs: rax, rcx, rdx, r8, r9, r10, r11, rbp, rsp */ __asm__ ("\n\ - movq %[NEW_SP], %%r10 # Load alt stack into r10 \n\ + pushq %%r9 # Push r9 on orig stack \n\ + movq %[NEW_SP], %%r9 # Load alt stack into r9 \n\ + subq $0x40, %%r9 # Make room on alt stack to \n\ + # save clobbered regs \n\ + movq %%rax, (%%r9) # Save other clobbered regs \n\ + movq %%rcx, 0x8(%%r9) \n\ + movq %%rdx, 0x10(%%r9) \n\ + movq %%r8, 0x18(%%r9) \n\ + movq %%r10, 0x20(%%r9) \n\ + movq %%r11, 0x28(%%r9) \n\ + movq %%rbp, 0x30(%%r9) \n\ + movq %%rsp, 0x38(%%r9) \n\ movl %[SIG], %%ecx # thissig to 1st arg reg \n\ movq %[SI], %%rdx # &thissi to 2nd arg reg \n\ movq %[CTX], %%r8 # thiscontext to 3rd arg reg \n\ movq %[FUNC], %%rax # thisfunc to rax \n\ - movq %%rbp, %%r12 # Save rbp in r12 \n\ - movq %%rsp, %%r13 # Save rsp in r13 \n\ - movq %%r10, %%rsp # Move alt stack into rsp \n\ + movq %%r9, %%rsp # Move alt stack into rsp \n\ xorq %%rbp, %%rbp # Set rbp to 0 \n\ - subq $32, %%rsp # Setup shadow space \n\ + subq $0x20, %%rsp # Setup shadow space \n\ call *%%rax # Call thisfunc \n\ - movq %%r12, %%rbp # Restore rbp \n\ - movq %%r13, %%rsp # Restore rsp \n" + addq $0x20, %%rsp # Revert shadow space \n\ + movq %%rsp, %%r9 # Restore clobbered regs \n\ + movq 0x38(%%r9), %%rsp \n\ + movq 0x30(%%r9), %%rbp \n\ + movq 0x28(%%r9), %%r11 \n\ + movq 0x20(%%r9), %%r10 \n\ + movq 0x18(%%r9), %%r8 \n\ + movq 0x10(%%r9), %%rdx \n\ + movq 0x8(%%r9), %%rcx \n\ + movq (%%r9), %%rax \n\ + popq %%r9 \n" : : [NEW_SP] "o" (new_sp), [SIG] "o" (thissig), [SI] "p" (&thissi), @@ -1624,11 +1644,17 @@ _cygtls::call_signal_handler () [FUNC] "o" (thisfunc) : "memory"); #else + /* Clobbered regs: eax, ecx, edx, ebp, esp */ __asm__ ("\n\ - push %%ecx # Save ecx on orig stack \n\ - push %%edx # Save edx on orig stack \n\ + push %%ecx # Push ecx on orig stack \n\ movl %[NEW_SP], %%ecx # Load alt stack into ecx \n\ - subl $20, %%ecx # Make room on new stack \n\ + subl $28, %%ecx # Make room on alt stack for \n\ + # clobbered regs and args to \n\ + # signal handler \n\ + movl %%eax, 12(%%ecx) # Save other clobbered regs \n\ + movl %%edx, 16(%%ecx) \n\ + movl %%ebp, 20(%%ecx) \n\ + movl %%esp, 24(%%ecx) \n\ movl %[SIG], %%edx # thissig to 1st arg slot \n\ movl %%edx, (%%ecx) \n\ movl %[SI], %%edx # &thissi to 2nd arg slot \n\ @@ -1636,16 +1662,15 @@ _cygtls::call_signal_handler () movl %[CTX], %%edx # thiscontext to 3rd arg slot\n\ movl %%edx, 8(%%ecx) \n\ movl %[FUNC], %%eax # thisfunc to eax \n\ - movl %%ebp, 12(%%ecx) # Save ebp on alt stack \n\ - movl %%esp, 16(%%ecx) # Save esp on alt stack \n\ - movl %%ecx, %%esp # Move stackbase into esp \n\ + movl %%ecx, %%esp # Move alt stack into esp \n\ xorl %%ebp, %%ebp # Set ebp to 0 \n\ call *%%eax # Call thisfunc \n\ - movl %%esp, %%ecx # Move alt stack to ecx \n\ - movl 12(%%ecx), %%ebp # Restore ebp \n\ - movl 16(%%ecx), %%esp # Restore esp \n\ - popl %%edx # Restore edx from orig stack\n\ - popl %%ecx # Restore ecx from orig stack\n" + movl %%esp, %%ecx # Restore clobbered regs \n\ + movl 24(%%ecx), %%esp \n\ + movl 20(%%ecx), %%ebp \n\ + movl 16(%%ecx), %%edx \n\ + movl 12(%%ecx), %%eax \n\ + popl %%ecx \n" : : [NEW_SP] "o" (new_sp), [SIG] "o" (thissig), [SI] "p" (&thissi), |