From 3a4630e6b417f5aaf4fb2b33ff545193f82310b9 Mon Sep 17 00:00:00 2001 From: gingerBill Date: Wed, 30 Mar 2022 16:15:23 +0100 Subject: Correct `atomic_cxchg_*` `atomic_cxchgweak_*` intrinsics behaviour to monotonic on failure for acq, rel, and acqrel --- src/llvm_backend_proc.cpp | 24 ++++++++++++++++-------- 1 file changed, 16 insertions(+), 8 deletions(-) (limited to 'src/llvm_backend_proc.cpp') diff --git a/src/llvm_backend_proc.cpp b/src/llvm_backend_proc.cpp index 27a6ec209..2d556b382 100644 --- a/src/llvm_backend_proc.cpp +++ b/src/llvm_backend_proc.cpp @@ -1372,12 +1372,20 @@ lbValue lb_build_builtin_proc(lbProcedure *p, Ast *expr, TypeAndValue const &tv, if (build_context.metrics.arch == TargetArch_i386 || build_context.metrics.arch == TargetArch_amd64) { LLVMTypeRef func_type = LLVMFunctionType(LLVMVoidTypeInContext(p->module->ctx), nullptr, 0, false); - LLVMValueRef the_asm = llvm_get_inline_asm(func_type, str_lit("pause"), {}); + LLVMValueRef the_asm = llvm_get_inline_asm(func_type, str_lit("pause"), {}, true); GB_ASSERT(the_asm != nullptr); LLVMBuildCall2(p->builder, func_type, the_asm, nullptr, 0, ""); } else if (build_context.metrics.arch == TargetArch_arm64) { LLVMTypeRef func_type = LLVMFunctionType(LLVMVoidTypeInContext(p->module->ctx), nullptr, 0, false); - LLVMValueRef the_asm = llvm_get_inline_asm(func_type, str_lit("yield"), {}); + // NOTE(bill, 2022-03-30): `isb` appears to a better option that `yield` + // See: https://bugs.java.com/bugdatabase/view_bug.do?bug_id=8258604 + LLVMValueRef the_asm = llvm_get_inline_asm(func_type, str_lit("isb"), {}, true); + GB_ASSERT(the_asm != nullptr); + LLVMBuildCall2(p->builder, func_type, the_asm, nullptr, 0, ""); + } else { + // NOTE: default to something to prevent optimization + LLVMTypeRef func_type = LLVMFunctionType(LLVMVoidTypeInContext(p->module->ctx), nullptr, 0, false); + LLVMValueRef the_asm = llvm_get_inline_asm(func_type, str_lit(""), {}, true); GB_ASSERT(the_asm != nullptr); LLVMBuildCall2(p->builder, func_type, the_asm, nullptr, 0, ""); } @@ -1794,18 +1802,18 @@ lbValue lb_build_builtin_proc(lbProcedure *p, Ast *expr, TypeAndValue const &tv, switch (id) { case BuiltinProc_atomic_cxchg: success_ordering = LLVMAtomicOrderingSequentiallyConsistent; failure_ordering = LLVMAtomicOrderingSequentiallyConsistent; weak = false; break; - case BuiltinProc_atomic_cxchg_acq: success_ordering = LLVMAtomicOrderingAcquire; failure_ordering = LLVMAtomicOrderingSequentiallyConsistent; weak = false; break; - case BuiltinProc_atomic_cxchg_rel: success_ordering = LLVMAtomicOrderingRelease; failure_ordering = LLVMAtomicOrderingSequentiallyConsistent; weak = false; break; - case BuiltinProc_atomic_cxchg_acqrel: success_ordering = LLVMAtomicOrderingAcquireRelease; failure_ordering = LLVMAtomicOrderingSequentiallyConsistent; weak = false; break; + case BuiltinProc_atomic_cxchg_acq: success_ordering = LLVMAtomicOrderingAcquire; failure_ordering = LLVMAtomicOrderingMonotonic; weak = false; break; + case BuiltinProc_atomic_cxchg_rel: success_ordering = LLVMAtomicOrderingRelease; failure_ordering = LLVMAtomicOrderingMonotonic; weak = false; break; + case BuiltinProc_atomic_cxchg_acqrel: success_ordering = LLVMAtomicOrderingAcquireRelease; failure_ordering = LLVMAtomicOrderingMonotonic; weak = false; break; case BuiltinProc_atomic_cxchg_relaxed: success_ordering = LLVMAtomicOrderingMonotonic; failure_ordering = LLVMAtomicOrderingMonotonic; weak = false; break; case BuiltinProc_atomic_cxchg_failrelaxed: success_ordering = LLVMAtomicOrderingSequentiallyConsistent; failure_ordering = LLVMAtomicOrderingMonotonic; weak = false; break; case BuiltinProc_atomic_cxchg_failacq: success_ordering = LLVMAtomicOrderingSequentiallyConsistent; failure_ordering = LLVMAtomicOrderingAcquire; weak = false; break; case BuiltinProc_atomic_cxchg_acq_failrelaxed: success_ordering = LLVMAtomicOrderingAcquire; failure_ordering = LLVMAtomicOrderingMonotonic; weak = false; break; case BuiltinProc_atomic_cxchg_acqrel_failrelaxed: success_ordering = LLVMAtomicOrderingAcquireRelease; failure_ordering = LLVMAtomicOrderingMonotonic; weak = false; break; case BuiltinProc_atomic_cxchgweak: success_ordering = LLVMAtomicOrderingSequentiallyConsistent; failure_ordering = LLVMAtomicOrderingSequentiallyConsistent; weak = false; break; - case BuiltinProc_atomic_cxchgweak_acq: success_ordering = LLVMAtomicOrderingAcquire; failure_ordering = LLVMAtomicOrderingSequentiallyConsistent; weak = true; break; - case BuiltinProc_atomic_cxchgweak_rel: success_ordering = LLVMAtomicOrderingRelease; failure_ordering = LLVMAtomicOrderingSequentiallyConsistent; weak = true; break; - case BuiltinProc_atomic_cxchgweak_acqrel: success_ordering = LLVMAtomicOrderingAcquireRelease; failure_ordering = LLVMAtomicOrderingSequentiallyConsistent; weak = true; break; + case BuiltinProc_atomic_cxchgweak_acq: success_ordering = LLVMAtomicOrderingAcquire; failure_ordering = LLVMAtomicOrderingMonotonic; weak = true; break; + case BuiltinProc_atomic_cxchgweak_rel: success_ordering = LLVMAtomicOrderingRelease; failure_ordering = LLVMAtomicOrderingMonotonic; weak = true; break; + case BuiltinProc_atomic_cxchgweak_acqrel: success_ordering = LLVMAtomicOrderingAcquireRelease; failure_ordering = LLVMAtomicOrderingMonotonic; weak = true; break; case BuiltinProc_atomic_cxchgweak_relaxed: success_ordering = LLVMAtomicOrderingMonotonic; failure_ordering = LLVMAtomicOrderingMonotonic; weak = true; break; case BuiltinProc_atomic_cxchgweak_failrelaxed: success_ordering = LLVMAtomicOrderingSequentiallyConsistent; failure_ordering = LLVMAtomicOrderingMonotonic; weak = true; break; case BuiltinProc_atomic_cxchgweak_failacq: success_ordering = LLVMAtomicOrderingSequentiallyConsistent; failure_ordering = LLVMAtomicOrderingAcquire; weak = true; break; -- cgit v1.2.3