Author: d0k
Date: Thu Mar 31 05:42:40 2016
New Revision: 265005
URL: http://llvm.org/viewvc/llvm-project?rev=265005&view=rev
Log:
[TTI] Let the cost model estimate ctpop costs based on legality
PPC has a vector popcount, this lets the vectorizer use the correct cost
for it. Tweak X86 test to use an intrinsic that's actually scalarized (we
have a somewhat efficient lowering for vector popcount using SSE, the
cost model finds that now).
Added:
llvm/trunk/test/Analysis/CostModel/PowerPC/popcnt.ll
Modified:
llvm/trunk/include/llvm/CodeGen/BasicTTIImpl.h
llvm/trunk/test/Analysis/CostModel/X86/scalarize.ll
Modified: llvm/trunk/include/llvm/CodeGen/BasicTTIImpl.h
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/include/llvm/CodeGen/BasicTTIImpl.h?rev=265005&r1=265004&r2=265005&view=diff
==============================================================================
--- llvm/trunk/include/llvm/CodeGen/BasicTTIImpl.h (original)
+++ llvm/trunk/include/llvm/CodeGen/BasicTTIImpl.h Thu Mar 31 05:42:40 2016
@@ -621,6 +621,7 @@ public:
unsigned getIntrinsicInstrCost(Intrinsic::ID IID, Type *RetTy,
ArrayRef<Type *> Tys) {
unsigned ISD = 0;
+ unsigned SingleCallCost = 10; // Library call cost. Make it expensive.
switch (IID) {
default: {
// Assume that we need to scalarize this intrinsic.
@@ -725,6 +726,13 @@ public:
case Intrinsic::masked_load:
return static_cast<T *>(this)
->getMaskedMemoryOpCost(Instruction::Load, RetTy, 0, 0);
+ case Intrinsic::ctpop:
+ ISD = ISD::CTPOP;
+ // In case of legalization use TCC_Expensive. This is cheaper than a
+ // library call but still not a cheap instruction.
+ SingleCallCost = TargetTransformInfo::TCC_Expensive;
+ break;
+ // FIXME: ctlz, cttz, ...
}
const TargetLoweringBase *TLI = getTLI();
@@ -785,7 +793,7 @@ public:
}
// This is going to be turned into a library call, make it expensive.
- return 10;
+ return SingleCallCost;
}
/// \brief Compute a cost of the given call instruction.
Added: llvm/trunk/test/Analysis/CostModel/PowerPC/popcnt.ll
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/test/Analysis/CostModel/PowerPC/popcnt.ll?rev=265005&view=auto
==============================================================================
--- llvm/trunk/test/Analysis/CostModel/PowerPC/popcnt.ll (added)
+++ llvm/trunk/test/Analysis/CostModel/PowerPC/popcnt.ll Thu Mar 31 05:42:40 2016
@@ -0,0 +1,11 @@
+; RUN: opt < %s -cost-model -analyze -mtriple=powerpc64-unknown-linux-gnu -mcpu=pwr8 | FileCheck %s
+target datalayout = "E-p:64:64:64-i1:8:8-i8:8:8-i16:16:16-i32:32:32-i64:64:64-f32:32:32-f64:64:64-f128:128:128-v128:128:128-n32:64"
+target triple = "powerpc64-unknown-linux-gnu"
+
+define <4 x i32> @test1(<4 x i32> %arg) {
+ ; CHECK: cost of 1 {{.*}} call <4 x i32> @llvm.ctpop.v4i32
+ %ctpop = call <4 x i32> @llvm.ctpop.v4i32(<4 x i32> %arg)
+ ret <4 x i32> %ctpop
+}
+
+declare <4 x i32> @llvm.ctpop.v4i32(<4 x i32>)
Modified: llvm/trunk/test/Analysis/CostModel/X86/scalarize.ll
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/test/Analysis/CostModel/X86/scalarize.ll?rev=265005&r1=265004&r2=265005&view=diff
==============================================================================
--- llvm/trunk/test/Analysis/CostModel/X86/scalarize.ll (original)
+++ llvm/trunk/test/Analysis/CostModel/X86/scalarize.ll Thu Mar 31 05:42:40 2016
@@ -13,8 +13,8 @@
declare %i4 @llvm.bswap.v4i32(%i4)
declare %i8 @llvm.bswap.v2i64(%i8)
-declare %i4 @llvm.ctpop.v4i32(%i4)
-declare %i8 @llvm.ctpop.v2i64(%i8)
+declare %i4 @llvm.cttz.v4i32(%i4)
+declare %i8 @llvm.cttz.v2i64(%i8)
; CHECK32-LABEL: test_scalarized_intrinsics
; CHECK64-LABEL: test_scalarized_intrinsics
@@ -28,12 +28,12 @@ define void @test_scalarized_intrinsics(
; CHECK64: cost of 6 {{.*}}bswap.v2i64
%r3 = call %i8 @llvm.bswap.v2i64(%i8 undef)
-; CHECK32: cost of 12 {{.*}}ctpop.v4i32
-; CHECK64: cost of 12 {{.*}}ctpop.v4i32
- %r4 = call %i4 @llvm.ctpop.v4i32(%i4 undef)
-; CHECK32: cost of 10 {{.*}}ctpop.v2i64
-; CHECK64: cost of 6 {{.*}}ctpop.v2i64
- %r5 = call %i8 @llvm.ctpop.v2i64(%i8 undef)
+; CHECK32: cost of 12 {{.*}}cttz.v4i32
+; CHECK64: cost of 12 {{.*}}cttz.v4i32
+ %r4 = call %i4 @llvm.cttz.v4i32(%i4 undef)
+; CHECK32: cost of 10 {{.*}}cttz.v2i64
+; CHECK64: cost of 6 {{.*}}cttz.v2i64
+ %r5 = call %i8 @llvm.cttz.v2i64(%i8 undef)
; CHECK32: ret
; CHECK64: ret