From 72a6e3d4040cde58e26a27febbf48671f025e056 Mon Sep 17 00:00:00 2001 From: Thomas Munro Date: Wed, 19 Nov 2025 00:00:13 +1300 Subject: [PATCH 2/2] jit: API changes for LLVM 22. The lifetime.end intrinsic can now only be used for stack memory allocated with alloca. We were using it to tell the optimizer that we are no longer interested in the arguments and null flag in a FunctionCallInfo struct, so it could avoid actually storing them if it managed to inline the function and keep everything in registers. It can't figure that out by itself because it's part of the ExecEvalStep struct and we scribble on it directly rather than building a new one on the stack. Instead, store the special poison value (undef would work too). This generates no actual code, but tells the optimizer that we are not interested in the values. Deform functions use LLVMBuildAlloca() for a stack variable, but that memory is reclaimed implicitly by the ret instruction. This code should probably do the same, but the change is non-trivial and not studied yet. https://github.com/llvm/llvm-project/pull/149310 https://llvm.org/docs/LangRef.html#llvm-lifetime-end-intrinsic https://llvm.org/docs/LangRef.html#i-alloca --- src/backend/jit/llvm/llvmjit_expr.c | 18 +++++++++++++----- 1 file changed, 13 insertions(+), 5 deletions(-) diff --git a/src/backend/jit/llvm/llvmjit_expr.c b/src/backend/jit/llvm/llvmjit_expr.c index f9c7f29e728..4dd2223bd2d 100644 --- a/src/backend/jit/llvm/llvmjit_expr.c +++ b/src/backend/jit/llvm/llvmjit_expr.c @@ -62,7 +62,9 @@ static LLVMValueRef build_EvalXFuncInt(LLVMBuilderRef b, LLVMModuleRef mod, LLVMValueRef v_state, ExprEvalStep *op, int natts, LLVMValueRef *v_args); +#if LLVM_VERSION_MAJOR < 22 static LLVMValueRef create_LifetimeEnd(LLVMModuleRef mod); +#endif /* macro making it easier to call ExecEval* functions */ #define build_EvalXFunc(b, mod, funcname, v_state, op, ...) \ @@ -3007,14 +3009,11 @@ BuildV1Call(LLVMJitContext *context, LLVMBuilderRef b, LLVMModuleRef mod, FunctionCallInfo fcinfo, LLVMValueRef *v_fcinfo_isnull) { - LLVMContextRef lc; LLVMValueRef v_fn; LLVMValueRef v_fcinfo_isnullp; LLVMValueRef v_retval; LLVMValueRef v_fcinfo; - lc = LLVMGetModuleContext(mod); - v_fn = llvm_function_reference(context, b, mod, fcinfo); v_fcinfo = l_ptr_const(fcinfo, l_ptr(StructFunctionCallInfoData)); @@ -3031,10 +3030,16 @@ BuildV1Call(LLVMJitContext *context, LLVMBuilderRef b, *v_fcinfo_isnull = l_load(b, TypeStorageBool, v_fcinfo_isnullp, ""); /* - * Add lifetime-end annotation, signaling that writes to memory don't have - * to be retained (important for inlining potential). + * Signal that writes to FunctionCallInfoData don't have to be retained + * (important for inlining potential). */ +#if LLVM_VERSION_MAJOR >= 22 + for (int i = 0; i < fcinfo->nargs; ++i) + LLVMBuildStore(b, LLVMGetPoison(StructNullableDatum), l_funcvaluep(b, v_fcinfo, i)); + LLVMBuildStore(b, LLVMGetPoison(TypeStorageBool), v_fcinfo_isnullp); +#else { + LLVMContextRef lc = LLVMGetModuleContext(mod); LLVMValueRef v_lifetime = create_LifetimeEnd(mod); LLVMValueRef params[2]; @@ -3046,6 +3051,7 @@ BuildV1Call(LLVMJitContext *context, LLVMBuilderRef b, params[1] = l_ptr_const(&fcinfo->isnull, l_ptr(LLVMInt8TypeInContext(lc))); l_call(b, LLVMGetFunctionType(v_lifetime), v_lifetime, params, lengthof(params), ""); } +#endif return v_retval; } @@ -3083,6 +3089,7 @@ build_EvalXFuncInt(LLVMBuilderRef b, LLVMModuleRef mod, const char *funcname, return v_ret; } +#if LLVM_VERSION_MAJOR < 22 static LLVMValueRef create_LifetimeEnd(LLVMModuleRef mod) { @@ -3112,3 +3119,4 @@ create_LifetimeEnd(LLVMModuleRef mod) return fn; } +#endif -- 2.52.0