database/postgres
1
0
Fork 0
mirror of https://github.com/postgres/postgres.git synced 2025-06-25 01:02:05 +03:00
Code Activity

Quick adaption of JIT tuple deforming to the fast default patch.

Browse Source 
Instead using memset to set tts_isnull, call the new
slot_getmissingattrs().

Also fix a bug (= instead of >=) in the code generation. Normally = is
correct, but when repeatedly deforming fields not in a
tuple (e.g. deform up to natts + 1 and then natts + 2) >= is needed.

Discussion: https://postgr.es/m/20180328010053.i2qvsuuusst4lgmc@alap3.anarazel.de
This commit is contained in:
Andres Freund
2018-03-27 21:03:10 -07:00
parent b4013b8e4a
commit f4f5845b31
6 changed files with 41 additions and 57 deletions
Download Patch File Download Diff File Expand all files Collapse all files

85
src/backend/jit/llvm/llvmjit_deform.c
View File

@ -21,14 +21,12 @@
#include <llvm-c/Core.h>
#include "access/htup_details.h"
#include "access/tupdesc_details.h"
#include "executor/tuptable.h"
#include "jit/llvmjit.h"
#include "jit/llvmjit_emit.h"
static LLVMValueRef get_memset(LLVMModuleRef mod);
/*
* Create a function that deforms a tuple of type desc up to natts columns.
*/
@ -100,10 +98,23 @@ slot_compile_deform(LLVMJitContext *context, TupleDesc desc, int natts)
*/
for (attnum = 0; attnum < desc->natts; attnum++)
{
if (TupleDescAttr(desc, attnum)->attnotnull)
{
Form_pg_attribute att = TupleDescAttr(desc, attnum);
/*
* If the column is possibly missing, we can't rely on its (or
* subsequent) NOT NULL constraints to indicate minimum attributes in
* the tuple, so stop here.
*/
if (att->atthasmissing)
break;
/*
* Column is NOT NULL and there've been no preceding missing columns,
* it's guaranteed that all columns up to here exist at least in the
* NULL bitmap.
*/
if (att->attnotnull)
guaranteed_column_number = attnum;
}
}
/* Create the signature and function */
@ -242,9 +253,8 @@ slot_compile_deform(LLVMJitContext *context, TupleDesc desc, int natts)
/*
* Check if's guaranteed the all the desired attributes are available in
* tuple. If so, we can start deforming. If not, need to make sure
* tts_values/isnull is set appropriately for columns not available in the
* tuple.
* tuple. If so, we can start deforming. If not, need to make sure to
* fetch the missing columns.
*/
if ((natts - 1) <= guaranteed_column_number)
{
@ -255,9 +265,7 @@ slot_compile_deform(LLVMJitContext *context, TupleDesc desc, int natts)
}
else
{
LLVMValueRef v_set;
LLVMValueRef v_startset;
LLVMValueRef v_params[5];
LLVMValueRef v_params[3];
/* branch if not all columns available */
LLVMBuildCondBr(b,
@ -271,19 +279,10 @@ slot_compile_deform(LLVMJitContext *context, TupleDesc desc, int natts)
/* if not, memset tts_isnull of relevant cols to true */
LLVMPositionBuilderAtEnd(b, b_adjust_unavail_cols);
v_set = LLVMBuildSub(b,
l_int16_const(attnum),
v_maxatt, "");
v_startset = LLVMBuildGEP(b, v_tts_nulls, &v_maxatt, 1, "");
v_params[0] = v_startset;
v_params[1] = l_int8_const(1);
v_params[2] = LLVMBuildZExt(b, v_set, LLVMInt32Type(), "");
v_params[3] = l_int32_const(1);
v_params[4] = LLVMConstInt(LLVMInt1Type(), 0, false);
LLVMBuildCall(b, get_memset(mod),
v_params[0] = v_slot;
v_params[1] = LLVMBuildZExt(b, v_maxatt, LLVMInt32Type(), "");
v_params[2] = l_int32_const(natts);
LLVMBuildCall(b, llvm_get_decl(mod, FuncSlotGetmissingattrs),
v_params, lengthof(v_params), "");
LLVMBuildBr(b, b_find_start);
}
@ -358,7 +357,7 @@ slot_compile_deform(LLVMJitContext *context, TupleDesc desc, int natts)
{
LLVMValueRef v_islast;
v_islast = LLVMBuildICmp(b, LLVMIntEQ,
v_islast = LLVMBuildICmp(b, LLVMIntUGE,
l_attno,
v_maxatt,
"heap_natts");
@ -366,7 +365,11 @@ slot_compile_deform(LLVMJitContext *context, TupleDesc desc, int natts)
}
LLVMPositionBuilderAtEnd(b, attstartblocks[attnum]);
/* check for nulls if necessary */
/*
* Check for nulls if necessary. No need to take missing attributes
* into account, because in case they're present the heaptuple's natts
* would have indicated that a slot_getmissingattrs() is needed.
*/
if (!att->attnotnull)
{
LLVMBasicBlockRef b_ifnotnull;
@ -699,31 +702,3 @@ slot_compile_deform(LLVMJitContext *context, TupleDesc desc, int natts)
return v_deform_fn;
}
static LLVMValueRef
get_memset(LLVMModuleRef mod)
{
LLVMTypeRef sig;
LLVMValueRef v_fn;
LLVMTypeRef param_types[5];
const char *nm = "llvm.memset.p0i8.i32";
v_fn = LLVMGetNamedFunction(mod, nm);
if (v_fn)
return v_fn;
param_types[0] = LLVMPointerType(LLVMInt8Type(), 0); /* addr */
param_types[1] = LLVMInt8Type(); /* val */
param_types[2] = LLVMInt32Type(); /* len */
param_types[3] = LLVMInt32Type(); /* align */
param_types[4] = LLVMInt1Type(); /* volatile */
sig = LLVMFunctionType(LLVMVoidType(), param_types, lengthof(param_types), 0);
v_fn = LLVMAddFunction(mod, nm, sig);
LLVMSetFunctionCallConv(v_fn, LLVMCCallConv);
Assert(LLVMGetIntrinsicID(v_fn));
return v_fn;
}