jit: Support opaque pointers in LLVM 16.

Remove use of LLVMGetElementType() and provide the type of all pointers
to LLVMBuildXXX() functions when emitting IR, as required by modern LLVM
versions[1].

 * For LLVM <= 14, we'll still use the old LLVMBuildXXX() functions.
 * For LLVM == 15, we'll continue to do the same, explicitly opting
   out of opaque pointer mode.
 * For LLVM >= 16, we'll use the new LLVMBuildXXX2() functions that take
   the extra type argument.

The difference is hidden behind some new IR emitting wrapper functions
l_load(), l_gep(), l_call() etc.  The change is mostly mechanical,
except that at each site the correct type had to be provided.

In some places we needed to do some extra work to get functions types,
including some new wrappers for C++ APIs that are not yet exposed by in
LLVM's C API, and some new "example" functions in llvmjit_types.c
because it's no longer possible to start from the function pointer type
and ask for the function type.

Back-patch to 12, because it's a little tricker in 11 and we agreed not
to put the latest LLVM support into the upcoming final release of 11.

[1] https://llvm.org/docs/OpaquePointers.html

Reviewed-by: Dmitry Dolgov <9erthalion6@gmail.com>
Reviewed-by: Ronan Dunklau <ronan.dunklau@aiven.io>
Reviewed-by: Andres Freund <andres@anarazel.de>
Discussion: https://postgr.es/m/CA%2BhUKGKNX_%3Df%2B1C4r06WETKTq0G4Z_7q4L4Fxn5WWpMycDj9Fw%40mail.gmail.com

1 files changed, 10 insertions, 10 deletions

diff --git a/src/include/jit/llvmjit.h b/src/include/jit/llvmjit.h
index be5980d999a..84aaaf5fc45 100644
--- a/src/include/jit/llvmjit.h
+++ b/src/include/jit/llvmjit.h
@@ -57,6 +57,8 @@ typedef struct LLVMJitContext
 	List	   *handles;
 } LLVMJitContext;
 
+/* llvm module containing information about types */
+extern PGDLLIMPORT LLVMModuleRef llvm_types_module;
 
 /* type and struct definitions */
 extern LLVMTypeRef TypeParamBool;
@@ -67,6 +69,8 @@ extern LLVMTypeRef TypeStorageBool;
 extern LLVMTypeRef StructNullableDatum;
 extern LLVMTypeRef StructTupleDescData;
 extern LLVMTypeRef StructHeapTupleData;
+extern LLVMTypeRef StructHeapTupleHeaderData;
+extern LLVMTypeRef StructMinimalTupleData;
 extern LLVMTypeRef StructTupleTableSlot;
 extern LLVMTypeRef StructHeapTupleTableSlot;
 extern LLVMTypeRef StructMinimalTupleTableSlot;
@@ -80,15 +84,7 @@ extern LLVMTypeRef StructAggStatePerTransData;
 extern LLVMTypeRef StructAggStatePerGroupData;
 
 extern LLVMValueRef AttributeTemplate;
-extern LLVMValueRef FuncStrlen;
-extern LLVMValueRef FuncVarsizeAny;
-extern LLVMValueRef FuncSlotGetmissingattrs;
-extern LLVMValueRef FuncSlotGetsomeattrsInt;
-extern LLVMValueRef FuncMakeExpandedObjectReadOnlyInternal;
-extern LLVMValueRef FuncExecEvalSubscriptingRef;
-extern LLVMValueRef FuncExecEvalSysVar;
-extern LLVMValueRef FuncExecAggTransReparent;
-extern LLVMValueRef FuncExecAggInitGroup;
+extern LLVMValueRef ExecEvalSubroutineTemplate;
 
 
 extern void llvm_enter_fatal_on_oom(void);
@@ -102,7 +98,9 @@ extern LLVMModuleRef llvm_mutable_module(LLVMJitContext *context);
 extern char *llvm_expand_funcname(LLVMJitContext *context, const char *basename);
 extern void *llvm_get_function(LLVMJitContext *context, const char *funcname);
 extern void llvm_split_symbol_name(const char *name, char **modname, char **funcname);
-extern LLVMValueRef llvm_get_decl(LLVMModuleRef mod, LLVMValueRef f);
+extern LLVMTypeRef llvm_pg_var_type(const char *varname);
+extern LLVMTypeRef llvm_pg_var_func_type(const char *varname);
+extern LLVMValueRef llvm_pg_func(LLVMModuleRef mod, const char *funcname);
 extern void llvm_copy_attributes(LLVMValueRef from, LLVMValueRef to);
 extern LLVMValueRef llvm_function_reference(LLVMJitContext *context,
 						LLVMBuilderRef builder,
@@ -140,6 +138,8 @@ extern char *LLVMGetHostCPUFeatures(void);
 #endif
 
 extern unsigned LLVMGetAttributeCountAtIndexPG(LLVMValueRef F, uint32 Idx);
+extern LLVMTypeRef LLVMGetFunctionReturnType(LLVMValueRef r);
+extern LLVMTypeRef LLVMGetFunctionType(LLVMValueRef r);
 
 #ifdef __cplusplus
 } /* extern "C" */