Hi all, Please find the attached patch which adds an ARM64 stub for the `_sigbe` routine in the gendef script.
Any feedback or nits are very welcome. The changes are documented with inline comments intended to be self-explanatory. please let me know if any part of this patch should be adjusted. Thanks for your time and review. Thanks & regards Thirumalai Nagalingam <[email protected]> In-lined patch: diff --git a/winsup/cygwin/scripts/gendef b/winsup/cygwin/scripts/gendef index 976e0f9f6..fdb970f6f 100755 --- a/winsup/cygwin/scripts/gendef +++ b/winsup/cygwin/scripts/gendef @@ -423,7 +423,43 @@ _sigfe: br x9 // Branch to real function .seh_endproc + .global _sigbe + .seh_proc _sigbe _sigbe: + .seh_endprologue + ldr x10, [x18, #0x8] // Load TLS base into x10 + mov w9, #1 // Constant value 1 for lock acquisition +3: 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 set stacklock atomically + cbnz w14, 3b // Retry if failed + cbz w13, 4f // If lock was free, continue + yield + b 3b // Retry acquiring the lock +4: + mov x9, #-8 // Set stack pointer decrement value +5: ldr x11, =_cygtls.stackptr // Load offset of stack pointer + add x12, x10, x11 // Compute final address of stack pointer + ldaxr x13, [x12] // Load current stack pointer atomically + add x14, x13, x9 // Compute new stack pointer value + stlxr w15, x14, [x12] // Attempt to update stack pointer atomically + cbnz w15, 5b // Retry if atomic update failed + sub x13, x13, #8 // Compute address where LR was saved + ldr x30, [x13] // Restore saved LR + ldr x11, =_cygtls.incyg // Load offset of incyg + add x12, x10, x11 // Compute final address of incyg + ldr w9, [x12] // Load current incyg value + sub w9, w9, #1 // Decrement incyg + str w9, [x12] // Store updated incyg value + ldr x11, =_cygtls.stacklock // Load offset of stacklock + add x12, x10, x11 // Compute final address of stacklock + ldr w9, [x12] // Load current stacklock value + sub w9, w9, #1 // Decrement stacklock (release lock) + stlr w9, [x12] // Store stacklock + ret // Return to caller using restored LR + .seh_endproc + .global sigdelayed .seh_proc sigdelayed sigdelayed:
Cygwin-gendef-Implement-_sigbe-function-for-TLS-stac.patch
Description: Cygwin-gendef-Implement-_sigbe-function-for-TLS-stac.patch
