From 6fda041e178bf44fae87cc56bef46db418dee0c7 Mon Sep 17 00:00:00 2001 From: Harold Brenes Date: Wed, 26 Mar 2025 19:25:06 -0400 Subject: [PATCH] Add `~{memory}` clobber to syscall intrinsics for platforms where it was not yet added. This fixes #4972 and #4588. As laytan asserts, there is no guarantee that a syscall will not modify memory that it just obtained from the user, or held onto via a previous syscall. Therefore this constraint should be required for all syscalls. --- src/llvm_backend_proc.cpp | 10 ++++++++++ 1 file changed, 10 insertions(+) diff --git a/src/llvm_backend_proc.cpp b/src/llvm_backend_proc.cpp index a835ae2c8..3c4913d50 100644 --- a/src/llvm_backend_proc.cpp +++ b/src/llvm_backend_proc.cpp @@ -2972,6 +2972,8 @@ gb_internal lbValue lb_build_builtin_proc(lbProcedure *p, Ast *expr, TypeAndValu constraints = gb_string_appendc(constraints, "}"); } + constraints = gb_string_appendc(constraints, ",~{memory}"); + inline_asm = llvm_get_inline_asm(func_type, make_string_c(asm_string), make_string_c(constraints)); } break; @@ -3034,6 +3036,8 @@ gb_internal lbValue lb_build_builtin_proc(lbProcedure *p, Ast *expr, TypeAndValu constraints = gb_string_appendc(constraints, "}"); } + constraints = gb_string_appendc(constraints, ",~{memory}"); + inline_asm = llvm_get_inline_asm(func_type, make_string_c(asm_string), make_string_c(constraints)); } break; @@ -3059,6 +3063,8 @@ gb_internal lbValue lb_build_builtin_proc(lbProcedure *p, Ast *expr, TypeAndValu constraints = gb_string_appendc(constraints, "}"); } + constraints = gb_string_appendc(constraints, ",~{memory}"); + inline_asm = llvm_get_inline_asm(func_type, make_string_c(asm_string), make_string_c(constraints)); } else { char asm_string[] = "svc #0"; @@ -3078,6 +3084,8 @@ gb_internal lbValue lb_build_builtin_proc(lbProcedure *p, Ast *expr, TypeAndValu constraints = gb_string_appendc(constraints, "}"); } + constraints = gb_string_appendc(constraints, ",~{memory}"); + inline_asm = llvm_get_inline_asm(func_type, make_string_c(asm_string), make_string_c(constraints)); } } @@ -3104,6 +3112,8 @@ gb_internal lbValue lb_build_builtin_proc(lbProcedure *p, Ast *expr, TypeAndValu constraints = gb_string_appendc(constraints, "}"); } + constraints = gb_string_appendc(constraints, ",~{memory}"); + inline_asm = llvm_get_inline_asm(func_type, make_string_c(asm_string), make_string_c(constraints)); } break;