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Additional cleanup to enable more broadcasts

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This commit is contained in:
Dmitry Babokin
2013-04-10 15:34:21 +04:00
parent 0704081d91
commit 4c35d9456a
4 changed files with 67 additions and 50 deletions
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71
ctx.cpp
View File

@@ -1380,10 +1380,10 @@ FunctionEmitContext::MasksAllEqual(llvm::Value *v1, llvm::Value *v2) {
}
llvm::Value *
FunctionEmitContext::ProgramIndex() {
FunctionEmitContext::ProgramIndexVector(bool is32bits) {
llvm::SmallVector<llvm::Constant*, 16> array;
for (int i = 0; i < g->target->getVectorWidth() ; ++i) {
llvm::Constant *C = LLVMInt32(i);
llvm::Constant *C = is32bits ? LLVMInt32(i) : LLVMInt64(i);
array.push_back(C);
}
@@ -1765,24 +1765,7 @@ FunctionEmitContext::SmearUniform(llvm::Value *value, const char *name) {
return ret;
}
// Generate the follwoing sequence:
// %broadcast_init.0 = insertelement <4 x i32> undef, i32 %val, i32 0
// %broadcast.1 = shufflevector <4 x i32> %smear.0, <4 x i32> undef,
// <4 x i32> zeroinitializer
//
llvm::Value *undef1 = llvm::UndefValue::get(vecType);
llvm::Value *undef2 = llvm::UndefValue::get(vecType);
// InsertElement
llvm::Twine tw1 = llvm::Twine("broadcast_init.") + llvm::Twine(name ? name : "");
llvm::Value *insert = InsertInst(undef1, value, 0, tw1.str().c_str());
// ShuffleVector
llvm::Constant *zeroVec = llvm::ConstantVector::getSplat(
g->target->getVectorWidth(),
llvm::Constant::getNullValue(llvm::Type::getInt32Ty(*g->ctx)));
llvm::Twine tw2 = llvm::Twine("broadcast.") + llvm::Twine(name ? name : "");
ret = ShuffleInst(insert, undef2, zeroVec, tw2.str().c_str());
ret = BroadcastValue(value, vecType, name);
return ret;
}
@@ -3187,6 +3170,45 @@ FunctionEmitContext::ShuffleInst(llvm::Value *v1, llvm::Value *v2, llvm::Value *
}
llvm::Value *
FunctionEmitContext::BroadcastValue(llvm::Value *v, llvm::Type* vecType,
const char *name) {
if (v == NULL || vecType == NULL) {
AssertPos(currentPos, m->errorCount > 0);
return NULL;
}
llvm::VectorType *ty = llvm::dyn_cast<llvm::VectorType>(vecType);
Assert(ty && ty->getVectorElementType() == v->getType());
if (name == NULL) {
char buf[32];
sprintf(buf, "_broadcast");
name = LLVMGetName(v, buf);
}
// Generate the follwoing sequence:
// %name_init.i = insertelement <4 x i32> undef, i32 %val, i32 0
// %name.i = shufflevector <4 x i32> %smear.0, <4 x i32> undef,
// <4 x i32> zeroinitializer
llvm::Value *undef1 = llvm::UndefValue::get(vecType);
llvm::Value *undef2 = llvm::UndefValue::get(vecType);
// InsertElement
llvm::Twine tw = llvm::Twine(name) + llvm::Twine("_init");
llvm::Value *insert = InsertInst(undef1, v, 0, tw.str().c_str());
// ShuffleVector
llvm::Constant *zeroVec = llvm::ConstantVector::getSplat(
vecType->getVectorNumElements(),
llvm::Constant::getNullValue(llvm::Type::getInt32Ty(*g->ctx)));
llvm::Value *ret = ShuffleInst(insert, undef2, zeroVec, name);
return ret;
}
llvm::PHINode *
FunctionEmitContext::PhiNode(llvm::Type *type, int count,
const char *name) {
@@ -3565,12 +3587,9 @@ FunctionEmitContext::addVaryingOffsetsIfNeeded(llvm::Value *ptr,
unifSize = SmearUniform(unifSize);
// Compute offset = <0, 1, .. > * unifSize
llvm::Value *varyingOffsets = llvm::UndefValue::get(unifSize->getType());
for (int i = 0; i < g->target->getVectorWidth(); ++i) {
llvm::Value *iValue = (g->target->is32Bit() || g->opt.force32BitAddressing) ?
LLVMInt32(i) : LLVMInt64(i);
varyingOffsets = InsertInst(varyingOffsets, iValue, i, "varying_delta");
}
bool is32bits = g->target->is32Bit() || g->opt.force32BitAddressing;
llvm::Value *varyingOffsets = ProgramIndexVector(is32bits);
llvm::Value *offset = BinaryOperator(llvm::Instruction::Mul, unifSize,
varyingOffsets);

9
ctx.h
View File

@@ -297,7 +297,7 @@ public:
/** Generate ConstantVector, which contains ProgramIndex, i.e.
< i32 0, i32 1, i32 2, i32 3> */
llvm::Value *ProgramIndex();
llvm::Value *ProgramIndexVector(bool is32bits = true);
/** Given a string, create an anonymous global variable to hold its
value and return the pointer to the string. */
@@ -504,9 +504,16 @@ public:
llvm::Value *InsertInst(llvm::Value *v, llvm::Value *eltVal, int elt,
const char *name = NULL);
/** This convenience method maps to an llvm::ShuffleVectorInst. */
llvm::Value *ShuffleInst(llvm::Value *v1, llvm::Value *v2, llvm::Value *mask,
const char *name = NULL);
/** This convenience method to generate broadcast pattern. It takes a value
and a vector type. Type of the value must match element type of the
vector. */
llvm::Value *BroadcastValue(llvm::Value *v, llvm::Type *vecType,
const char *name = NULL);
llvm::PHINode *PhiNode(llvm::Type *type, int count,
const char *name = NULL);
llvm::Instruction *SelectInst(llvm::Value *test, llvm::Value *val0,

11
expr.cpp
View File

@@ -3905,11 +3905,7 @@ lAddVaryingOffsetsIfNeeded(FunctionEmitContext *ctx, llvm::Value *ptr,
return ptr;
// Onward: compute the per lane offsets.
llvm::Value *varyingOffsets =
llvm::UndefValue::get(LLVMTypes::Int32VectorType);
for (int i = 0; i < g->target->getVectorWidth(); ++i)
varyingOffsets = ctx->InsertInst(varyingOffsets, LLVMInt32(i), i,
"varying_delta");
llvm::Value *varyingOffsets = ctx->ProgramIndexVector();
// And finally add the per-lane offsets. Note that we lie to the GEP
// call and tell it that the pointers are to uniform elements and not
@@ -6768,9 +6764,8 @@ TypeCastExpr::GetValue(FunctionEmitContext *ctx) const {
if (!conv)
return NULL;
llvm::Value *cast = llvm::UndefValue::get(toType->LLVMType(g->ctx));
for (int i = 0; i < toVector->GetElementCount(); ++i)
cast = ctx->InsertInst(cast, conv, i);
llvm::Value *cast = ctx->BroadcastValue(conv, toType->LLVMType(g->ctx));
return cast;
}
else if (toPointerType != NULL) {

26
stmt.cpp
View File

@@ -1272,11 +1272,8 @@ lUpdateVaryingCounter(int dim, int nDims, FunctionEmitContext *ctx,
const std::vector<int> &spans) {
// Smear the uniform counter value out to be varying
llvm::Value *counter = ctx->LoadInst(uniformCounterPtr);
llvm::Value *smearCounter =
llvm::UndefValue::get(LLVMTypes::Int32VectorType);
for (int i = 0; i < g->target->getVectorWidth(); ++i)
smearCounter =
ctx->InsertInst(smearCounter, counter, i, "smear_counter");
llvm::Value *smearCounter = ctx->BroadcastValue(
counter, LLVMTypes::Int32VectorType, "smear_counter");
// Figure out the offsets; this is a little bit tricky. As an example,
// consider a 2D tiled foreach loop, where we're running 8-wide and
@@ -1517,9 +1514,9 @@ ForeachStmt::EmitCode(FunctionEmitContext *ctx) const {
lUpdateVaryingCounter(i, nDims, ctx, uniformCounterPtrs[i],
dimVariables[i]->storagePtr, span);
llvm::Value *smearEnd = llvm::UndefValue::get(LLVMTypes::Int32VectorType);
for (int j = 0; j < g->target->getVectorWidth(); ++j)
smearEnd = ctx->InsertInst(smearEnd, endVals[i], j, "smear_end");
llvm::Value *smearEnd = ctx->BroadcastValue(
endVals[i], LLVMTypes::Int32VectorType, "smear_end");
// Do a vector compare of its value to the end value to generate a
// mask for this last bit of work.
llvm::Value *emask =
@@ -1662,9 +1659,9 @@ ForeachStmt::EmitCode(FunctionEmitContext *ctx) const {
ctx->SetCurrentBasicBlock(bbPartial); {
llvm::Value *varyingCounter =
ctx->LoadInst(dimVariables[nDims-1]->storagePtr);
llvm::Value *smearEnd = llvm::UndefValue::get(LLVMTypes::Int32VectorType);
for (int j = 0; j < g->target->getVectorWidth(); ++j)
smearEnd = ctx->InsertInst(smearEnd, endVals[nDims-1], j, "smear_end");
llvm::Value *smearEnd = ctx->BroadcastValue(
endVals[nDims-1], LLVMTypes::Int32VectorType, "smear_end");
llvm::Value *emask =
ctx->CmpInst(llvm::Instruction::ICmp, llvm::CmpInst::ICMP_SLT,
varyingCounter, smearEnd);
@@ -1758,9 +1755,8 @@ ForeachStmt::EmitCode(FunctionEmitContext *ctx) const {
llvm::Value *varyingCounter =
lUpdateVaryingCounter(nDims-1, nDims, ctx, uniformCounterPtrs[nDims-1],
dimVariables[nDims-1]->storagePtr, span);
llvm::Value *smearEnd = llvm::UndefValue::get(LLVMTypes::Int32VectorType);
for (int j = 0; j < g->target->getVectorWidth(); ++j)
smearEnd = ctx->InsertInst(smearEnd, endVals[nDims-1], j, "smear_end");
llvm::Value *smearEnd = ctx->BroadcastValue(
endVals[nDims-1], LLVMTypes::Int32VectorType, "smear_end");
llvm::Value *emask =
ctx->CmpInst(llvm::Instruction::ICmp, llvm::CmpInst::ICMP_SLT,
varyingCounter, smearEnd);
@@ -1993,7 +1989,7 @@ ForeachActiveStmt::EmitCode(FunctionEmitContext *ctx) const {
// math...)
// Get the "program index" vector value
llvm::Value *programIndex = ctx->ProgramIndex();
llvm::Value *programIndex = ctx->ProgramIndexVector();
// And smear the current lane out to a vector
llvm::Value *firstSet32 =