https://sourceware.org/git/gitweb.cgi?p=newlib-cygwin.git;h=5e86032e3e84938e61d95989e464495b5a09b043
commit 5e86032e3e84938e61d95989e464495b5a09b043 Author: Thirumalai Nagalingam <[email protected]> AuthorDate: Sat Dec 6 19:16:21 2025 +0530 Commit: Corinna Vinschen <[email protected]> CommitDate: Fri Jan 16 19:48:53 2026 +0100 Cygwin: gendef: Implement _sigfe function for TLS handling on AArch64 Signed-off-by: Thirumalai Nagalingam <[email protected]> Diff: --- winsup/cygwin/scripts/gendef | 37 +++++++++++++++++++++++++++++++++++++ 1 file changed, 37 insertions(+) diff --git a/winsup/cygwin/scripts/gendef b/winsup/cygwin/scripts/gendef index 32ceb357802c..ab57739fa5e6 100755 --- a/winsup/cygwin/scripts/gendef +++ b/winsup/cygwin/scripts/gendef @@ -385,7 +385,44 @@ _sigfe_maybe: # stack is aligned on entry! ret .seh_endproc + .seh_proc _sigfe _sigfe: + .seh_endprologue + ldr x10, [x18, #0x8] // Load TLS base into x10 + mov w9, #1 // constant value for lock acquisition +0: ldr x11, =_cygtls.stacklock // Load offset of stacklock + add x12, x10, x11 // Compute final address of stacklock + ldaxr w13, [x12] // Load current stacklock value atomically + stlxr w14, w9, [x12] // Attempt to store 1 to stacklock atomically + cbnz w14, 0b // Retry if atomic store failed + cbz w13, 1f // If lock was free, proceed + yield + b 0b // Retry acquiring the lock +1: + ldr x11, =_cygtls.incyg // Load offset of incyg + add x12, x10, x11 // Compute final address of incyg + ldr w9, [x12] // Load current incyg value + add w9, w9, #1 // Increment incyg + str w9, [x12] // Store updated incyg value + mov x9, #8 // Set stack frame size increment (8 bytes) +2: ldr x11, =_cygtls.stackptr // Load offset of stack pointer + add x12, x10, x11 // Compute final address of stack pointer + ldaxr x13, [x12] // Atomically load current stack pointer + add x14, x13, x9 // Compute new stack pointer value + stlxr w15, x14, [x12] // Attempt to update stack pointer atomically + cbnz w15, 2b // Retry if atomic update failed + str x30, [x13] // Save LR(return address) on stack + adr x11, _sigbe // Load address of _sigbe + mov x30, x11 // Set LR = _sigbe + ldr x11, =_cygtls.stacklock // Load offset of stacklock TLS variable + add x12, x10, x11 // Compute final address of stacklock + ldr w9, [x12] // Load current stacklock value + sub w9, w9, #1 // Decrement stacklock to release lock + stlr w9, [x12] // Store stacklock value (release lock) + ldr x9, [sp], #16 // Pop real func address from stack + br x9 // Branch to real function + .seh_endproc + _sigbe: .global sigdelayed sigdelayed:
