/**************************************************************************
*
* Copyright 2009 VMware, Inc.
* All Rights Reserved.
*
* Permission is hereby granted, free of charge, to any person obtaining a
* copy of this software and associated documentation files (the
* "Software"), to deal in the Software without restriction, including
* without limitation the rights to use, copy, modify, merge, publish,
* distribute, sub license, and/or sell copies of the Software, and to
* permit persons to whom the Software is furnished to do so, subject to
* the following conditions:
*
* The above copyright notice and this permission notice (including the
* next paragraph) shall be included in all copies or substantial portions
* of the Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
* OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
* MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT.
* IN NO EVENT SHALL VMWARE AND/OR ITS SUPPLIERS BE LIABLE FOR
* ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT,
* TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE
* SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
*
**************************************************************************/
/**
* @file
* Helper functions for constant building.
*
* @author Jose Fonseca <jfonseca@vmware.com>
*/
#include <float.h>
#include "util/u_debug.h"
#include "util/u_math.h"
#include "util/u_half.h"
#include "lp_bld_type.h"
#include "lp_bld_const.h"
#include "lp_bld_init.h"
unsigned
lp_mantissa(struct lp_type type)
{
assert(type.floating);
if(type.floating) {
switch(type.width) {
case 16:
return 10;
case 32:
return 23;
case 64:
return 52;
default:
assert(0);
return 0;
}
}
else {
if(type.sign)
return type.width - 1;
else
return type.width;
}
}
/**
* Shift of the unity.
*
* Same as lp_const_scale(), but in terms of shifts.
*/
unsigned
lp_const_shift(struct lp_type type)
{
if(type.floating)
return 0;
else if(type.fixed)
return type.width/2;
else if(type.norm)
return type.sign ? type.width - 1 : type.width;
else
return 0;
}
unsigned
lp_const_offset(struct lp_type type)
{
if(type.floating || type.fixed)
return 0;
else if(type.norm)
return 1;
else
return 0;
}
/**
* Scaling factor between the LLVM native value and its interpretation.
*
* This is 1.0 for all floating types and unnormalized integers, and something
* else for the fixed points types and normalized integers.
*/
double
lp_const_scale(struct lp_type type)
{
unsigned long long llscale;
double dscale;
llscale = (unsigned long long)1 << lp_const_shift(type);
llscale -= lp_const_offset(type);
dscale = (double)llscale;
assert((unsigned long long)dscale == llscale);
return dscale;
}
/**
* Minimum value representable by the type.
*/
double
lp_const_min(struct lp_type type)
{
unsigned bits;
if(!type.sign)
return 0.0;
if(type.norm)
return -1.0;
if (type.floating) {
switch(type.width) {
case 16:
return -65504;
case 32:
return -FLT_MAX;
case 64:
return -DBL_MAX;
default:
assert(0);
return 0.0;
}
}
if(type.fixed)
/* FIXME: consider the fractional bits? */
bits = type.width / 2 - 1;
else
bits = type.width - 1;
return (double)-((long long)1 << bits);
}
/**
* Maximum value representable by the type.
*/
double
lp_const_max(struct lp_type type)
{
unsigned bits;
if(type.norm)
return 1.0;
if (type.floating) {
switch(type.width) {
case 16:
return 65504;
case 32:
return FLT_MAX;
case 64:
return DBL_MAX;
default:
assert(0);
return 0.0;
}
}
if(type.fixed)
bits = type.width / 2;
else
bits = type.width;
if(type.sign)
bits -= 1;
return (double)(((unsigned long long)1 << bits) - 1);
}
double
lp_const_eps(struct lp_type type)
{
if (type.floating) {
switch(type.width) {
case 16:
return 2E-10;
case 32:
return FLT_EPSILON;
case 64:
return DBL_EPSILON;
default:
assert(0);
return 0.0;
}
}
else {
double scale = lp_const_scale(type);
return 1.0/scale;
}
}
LLVMValueRef
lp_build_undef(struct gallivm_state *gallivm, struct lp_type type)
{
LLVMTypeRef vec_type = lp_build_vec_type(gallivm, type);
return LLVMGetUndef(vec_type);
}
LLVMValueRef
lp_build_zero(struct gallivm_state *gallivm, struct lp_type type)
{
if (type.length == 1) {
if (type.floating)
return lp_build_const_float(gallivm, 0.0);
else
return LLVMConstInt(LLVMIntTypeInContext(gallivm->context, type.width), 0, 0);
}
else {
LLVMTypeRef vec_type = lp_build_vec_type(gallivm, type);
return LLVMConstNull(vec_type);
}
}
LLVMValueRef
lp_build_one(struct gallivm_state *gallivm, struct lp_type type)
{
LLVMTypeRef elem_type;
LLVMValueRef elems[LP_MAX_VECTOR_LENGTH];
unsigned i;
assert(type.length <= LP_MAX_VECTOR_LENGTH);
elem_type = lp_build_elem_type(gallivm, type);
if(type.floating && type.width == 16)
elems[0] = LLVMConstInt(elem_type, util_float_to_half(1.0f), 0);
else if(type.floating)
elems[0] = LLVMConstReal(elem_type, 1.0);
else if(type.fixed)
elems[0] = LLVMConstInt(elem_type, 1LL << (type.width/2), 0);
else if(!type.norm)
elems[0] = LLVMConstInt(elem_type, 1, 0);
else if(type.sign)
elems[0] = LLVMConstInt(elem_type, (1LL << (type.width - 1)) - 1, 0);
else {
/* special case' -- 1.0 for normalized types is more easily attained if
* we start with a vector consisting of all bits set */
LLVMTypeRef vec_type = LLVMVectorType(elem_type, type.length);
LLVMValueRef vec = LLVMConstAllOnes(vec_type);
#if 0
if(type.sign)
/* TODO: Unfortunately this caused "Tried to create a shift operation
* on a non-integer type!" */
vec = LLVMConstLShr(vec, lp_build_const_int_vec(type, 1));
#endif
return vec;
}
for(i = 1; i < type.length; ++i)
elems[i] = elems[0];
if (type.length == 1)
return elems[0];
else
return LLVMConstVector(elems, type.length);
}
/**
* Build constant-valued element from a scalar value.
*/
LLVMValueRef
lp_build_const_elem(struct gallivm_state *gallivm,
struct lp_type type,
double val)
{
LLVMTypeRef elem_type = lp_build_elem_type(gallivm, type);
LLVMValueRef elem;
if(type.floating && type.width == 16) {
elem = LLVMConstInt(elem_type, util_float_to_half((float)val), 0);
} else if(type.floating) {
elem = LLVMConstReal(elem_type, val);
}
else {
double dscale = lp_const_scale(type);
elem = LLVMConstInt(elem_type, round(val*dscale), 0);
}
return elem;
}
/**
* Build constant-valued vector from a scalar value.
*/
LLVMValueRef
lp_build_const_vec(struct gallivm_state *gallivm, struct lp_type type,
double val)
{
if (type.length == 1) {
return lp_build_const_elem(gallivm, type, val);
} else {
LLVMValueRef elems[LP_MAX_VECTOR_LENGTH];
unsigned i;
elems[0] = lp_build_const_elem(gallivm, type, val);
for(i = 1; i < type.length; ++i)
elems[i] = elems[0];
return LLVMConstVector(elems, type.length);
}
}
LLVMValueRef
lp_build_const_int_vec(struct gallivm_state *gallivm, struct lp_type type,
long long val)
{
LLVMTypeRef elem_type = lp_build_int_elem_type(gallivm, type);
LLVMValueRef elems[LP_MAX_VECTOR_LENGTH];
unsigned i;
assert(type.length <= LP_MAX_VECTOR_LENGTH);
for(i = 0; i < type.length; ++i)
elems[i] = LLVMConstInt(elem_type, val, type.sign ? 1 : 0);
if (type.length == 1)
return elems[0];
return LLVMConstVector(elems, type.length);
}
LLVMValueRef
lp_build_const_aos(struct gallivm_state *gallivm,
struct lp_type type,
double r, double g, double b, double a,
const unsigned char *swizzle)
{
const unsigned char default_swizzle[4] = {0, 1, 2, 3};
LLVMTypeRef elem_type;
LLVMValueRef elems[LP_MAX_VECTOR_LENGTH];
unsigned i;
assert(type.length % 4 == 0);
assert(type.length <= LP_MAX_VECTOR_LENGTH);
elem_type = lp_build_elem_type(gallivm, type);
if(swizzle == NULL)
swizzle = default_swizzle;
elems[swizzle[0]] = lp_build_const_elem(gallivm, type, r);
elems[swizzle[1]] = lp_build_const_elem(gallivm, type, g);
elems[swizzle[2]] = lp_build_const_elem(gallivm, type, b);
elems[swizzle[3]] = lp_build_const_elem(gallivm, type, a);
for(i = 4; i < type.length; ++i)
elems[i] = elems[i % 4];
return LLVMConstVector(elems, type.length);
}
/**
* @param mask TGSI_WRITEMASK_xxx
*/
LLVMValueRef
lp_build_const_mask_aos(struct gallivm_state *gallivm,
struct lp_type type,
unsigned mask)
{
LLVMTypeRef elem_type = LLVMIntTypeInContext(gallivm->context, type.width);
LLVMValueRef masks[LP_MAX_VECTOR_LENGTH];
unsigned i, j;
assert(type.length <= LP_MAX_VECTOR_LENGTH);
for (j = 0; j < type.length; j += 4) {
for( i = 0; i < 4; ++i) {
masks[j + i] = LLVMConstInt(elem_type,
mask & (1 << i) ? ~0ULL : 0,
1);
}
}
return LLVMConstVector(masks, type.length);
}
/**
* Performs lp_build_const_mask_aos, but first swizzles the mask
*/
LLVMValueRef
lp_build_const_mask_aos_swizzled(struct gallivm_state *gallivm,
struct lp_type type,
unsigned mask,
const unsigned char *swizzle)
{
mask =
((mask & (1 << swizzle[0])) >> swizzle[0])
| (((mask & (1 << swizzle[1])) >> swizzle[1]) << 1)
| (((mask & (1 << swizzle[2])) >> swizzle[2]) << 2)
| (((mask & (1 << swizzle[3])) >> swizzle[3]) << 3);
return lp_build_const_mask_aos(gallivm, type, mask);
}
/**
* Build a zero-terminated constant string.
*/
LLVMValueRef
lp_build_const_string(struct gallivm_state *gallivm,
const char *str)
{
unsigned len = strlen(str) + 1;
LLVMTypeRef i8 = LLVMInt8TypeInContext(gallivm->context);
LLVMValueRef string = LLVMAddGlobal(gallivm->module, LLVMArrayType(i8, len), "");
LLVMSetGlobalConstant(string, TRUE);
LLVMSetLinkage(string, LLVMInternalLinkage);
LLVMSetInitializer(string, LLVMConstStringInContext(gallivm->context, str, len, TRUE));
string = LLVMConstBitCast(string, LLVMPointerType(i8, 0));
return string;
}
/**
* Build a callable function pointer.
*
* We use function pointer constants instead of LLVMAddGlobalMapping()
* to work around a bug in LLVM 2.6, and for efficiency/simplicity.
*/
LLVMValueRef
lp_build_const_func_pointer(struct gallivm_state *gallivm,
const void *ptr,
LLVMTypeRef ret_type,
LLVMTypeRef *arg_types,
unsigned num_args,
const char *name)
{
LLVMTypeRef function_type;
LLVMValueRef function;
function_type = LLVMFunctionType(ret_type, arg_types, num_args, 0);
function = lp_build_const_int_pointer(gallivm, ptr);
function = LLVMBuildBitCast(gallivm->builder, function,
LLVMPointerType(function_type, 0),
name);
return function;
}