[PATCH] D90597: [CostModel] Make target intrinsics cheap by default

[Dave Green via Phabricator via llvm-commits]

dmgreen updated this revision to Diff 302274.
dmgreen added a comment.

Yeah that makes sense. My tests were not unhappy about moving it.


CHANGES SINCE LAST ACTION
  https://reviews.llvm.org/D90597/new/

https://reviews.llvm.org/D90597

Files:
  llvm/include/llvm/CodeGen/BasicTTIImpl.h
  llvm/include/llvm/IR/Function.h
  llvm/lib/IR/Function.cpp
  llvm/test/Analysis/CostModel/ARM/target-intrinsics.ll


Index: llvm/test/Analysis/CostModel/ARM/target-intrinsics.ll
===================================================================
--- llvm/test/Analysis/CostModel/ARM/target-intrinsics.ll
+++ llvm/test/Analysis/CostModel/ARM/target-intrinsics.ll
@@ -9,7 +9,7 @@
 ; CHECK-THUMB2-RECIP-NEXT:  Cost Model: Found an estimated cost of 1 for instruction: %t1 = call i32 @llvm.arm.ssat(i32 undef, i32 undef)
 ; CHECK-THUMB2-RECIP-NEXT:  Cost Model: Found an estimated cost of 1 for instruction: %t2 = tail call { <8 x half>, <8 x half> } @llvm.arm.mve.vld2q.v8f16.p0f16(half* undef)
 ; CHECK-THUMB2-RECIP-NEXT:  Cost Model: Found an estimated cost of 1 for instruction: %t3 = call { i32, i32 } @llvm.arm.mve.sqrshrl(i32 undef, i32 undef, i32 undef, i32 48)
-; CHECK-THUMB2-RECIP-NEXT:  Cost Model: Found an estimated cost of 135 for instruction: %t4 = tail call { i32, i32 } @llvm.arm.mve.vmlldava.v8i16(i32 0, i32 0, i32 0, i32 0, i32 0, <8 x i16> undef, <8 x i16> undef)
+; CHECK-THUMB2-RECIP-NEXT:  Cost Model: Found an estimated cost of 1 for instruction: %t4 = tail call { i32, i32 } @llvm.arm.mve.vmlldava.v8i16(i32 0, i32 0, i32 0, i32 0, i32 0, <8 x i16> undef, <8 x i16> undef)
 ; CHECK-THUMB2-RECIP-NEXT:  Cost Model: Found an estimated cost of 0 for instruction: ret void
 ;
 ; CHECK-THUMB2-LAT-LABEL: 'intrinsics'
Index: llvm/lib/IR/Function.cpp
===================================================================
--- llvm/lib/IR/Function.cpp
+++ llvm/lib/IR/Function.cpp
@@ -640,8 +640,12 @@
 #include "llvm/IR/IntrinsicImpl.inc"
 #undef GET_INTRINSIC_TARGET_DATA
 
+bool Function::isTargetIntrinsic(Intrinsic::ID IID) {
+  return IID > TargetInfos[0].Count;
+}
+
 bool Function::isTargetIntrinsic() const {
-  return IntID > TargetInfos[0].Count;
+  return isTargetIntrinsic(IntID);
 }
 
 /// Find the segment of \c IntrinsicNameTable for intrinsics with the same
Index: llvm/include/llvm/IR/Function.h
===================================================================
--- llvm/include/llvm/IR/Function.h
+++ llvm/include/llvm/IR/Function.h
@@ -199,6 +199,10 @@
   /// returns Intrinsic::not_intrinsic!
   bool isIntrinsic() const { return HasLLVMReservedName; }
 
+  /// isTargetIntrinsic - Returns true if this IID is an intrinsic specific to a
+  /// certain target. If this is a generic intrinsic, false is returned.
+  static bool isTargetIntrinsic(Intrinsic::ID IID);
+
   /// isTargetIntrinsic - Returns true if this function is an intrinsic and the
   /// intrinsic is specific to a certain target. If this is not an intrinsic
   /// or a generic intrinsic, false is returned.
Index: llvm/include/llvm/CodeGen/BasicTTIImpl.h
===================================================================
--- llvm/include/llvm/CodeGen/BasicTTIImpl.h
+++ llvm/include/llvm/CodeGen/BasicTTIImpl.h
@@ -1133,6 +1133,11 @@
     if (BaseT::getIntrinsicInstrCost(ICA, CostKind) == 0)
       return 0;
 
+    // Assume that target intrinsics are cheap
+    Intrinsic::ID IID = ICA.getID();
+    if (Function::isTargetIntrinsic(IID))
+      return TargetTransformInfo::TCC_Basic;
+
     if (ICA.isTypeBasedOnly())
       return getTypeBasedIntrinsicInstrCost(ICA, CostKind);
 
@@ -1149,7 +1154,6 @@
     const IntrinsicInst *I = ICA.getInst();
     const SmallVectorImpl<const Value *> &Args = ICA.getArgs();
     FastMathFlags FMF = ICA.getFlags();
-    Intrinsic::ID IID = ICA.getID();
     switch (IID) {
     default:
       // FIXME: all cost kinds should default to the same thing?


-------------- next part --------------
A non-text attachment was scrubbed...
Name: D90597.302274.patch
Type: text/x-patch
Size: 3483 bytes
Desc: not available
URL: <http://lists.llvm.org/pipermail/llvm-commits/attachments/20201102/93e37473/attachment.bin>