From cb62101787555b7b32607b431fdfe6fcc8f3830f Mon Sep 17 00:00:00 2001 From: Kewen Lin Date: Tue, 9 Jan 2024 23:05:13 -0600 Subject: [PATCH] strub: Only unbias stack point for SPARC_STACK_BOUNDARY_HACK [PR113100] As PR113100 shows, the unbiasing introduced by r14-6737 can cause the scrubbing to overrun and screw some critical data on stack like saved toc base consequently cause segfault. By checking PR112917, IMHO we should keep this unbiasing guarded under SPARC_STACK_BOUNDARY_HACK (TARGET_ARCH64 && TARGET_STACK_BIAS), similar to some existing code special treating SPARC stack bias. PR middle-end/113100 gcc/ChangeLog: * builtins.cc (expand_builtin_stack_address): Guard stack point adjustment with SPARC_STACK_BOUNDARY_HACK. --- gcc/builtins.cc | 5 ++++- 1 file changed, 4 insertions(+), 1 deletion(-) diff --git a/gcc/builtins.cc b/gcc/builtins.cc index d1767596ced..09f2354f114 100644 --- a/gcc/builtins.cc +++ b/gcc/builtins.cc @@ -5450,6 +5450,7 @@ expand_builtin_stack_address () rtx ret = convert_to_mode (ptr_mode, copy_to_reg (stack_pointer_rtx), STACK_UNSIGNED); +#ifdef SPARC_STACK_BOUNDARY_HACK /* Unbias the stack pointer, bringing it to the boundary between the stack area claimed by the active function calling this builtin, and stack ranges that could get clobbered if it called another @@ -5476,7 +5477,9 @@ expand_builtin_stack_address () (caller) function's active area as well, whereas those pushed or allocated temporarily for a call are regarded as part of the callee's stack range, rather than the caller's. */ - ret = plus_constant (ptr_mode, ret, STACK_POINTER_OFFSET); + if (SPARC_STACK_BOUNDARY_HACK) + ret = plus_constant (ptr_mode, ret, STACK_POINTER_OFFSET); +#endif return force_reg (ptr_mode, ret); }