[ConstantRange] Add setSizeSmallerThanOf method.
Summary:
ConstantRange class currently has a method getSetSize, which is mostly used to
compare set sizes of two constant ranges (there is only one spot where it's used
in a slightly different scenario). This patch introduces setSizeSmallerThanOf
method, which does such comparison in a more efficient way. In the original
method we have to extend our types to (BitWidth+1), which can result it using
slow case of APInt, extra memory allocations, etc.
The change is supposed to not change any functionality, but it slightly improves
compile time. Here is compile time improvements that I observed on CTMark:
* tramp3d-v4 -2.02%
* pairlocalalign -1.82%
* lencod -1.67%
Reviewers: sanjoy, atrick, pete
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D31104
llvm-svn: 298236
diff --git a/llvm/lib/IR/ConstantRange.cpp b/llvm/lib/IR/ConstantRange.cpp
index f940955..f1826c0 100644
--- a/llvm/lib/IR/ConstantRange.cpp
+++ b/llvm/lib/IR/ConstantRange.cpp
@@ -272,6 +272,22 @@
return (Upper - Lower).zext(getBitWidth()+1);
}
+/// isSizeStrictlySmallerThanOf - Compare set size of this range with the range
+/// CR.
+/// This function is faster than comparing results of getSetSize for the two
+/// ranges, because we don't need to extend bitwidth of APInts we're operating
+/// with.
+///
+bool
+ConstantRange::isSizeStrictlySmallerThanOf(const ConstantRange &Other) const {
+ assert(getBitWidth() == Other.getBitWidth());
+ if (isFullSet())
+ return false;
+ if (Other.isFullSet())
+ return true;
+ return (Upper - Lower).ult(Other.Upper - Other.Lower);
+}
+
/// getUnsignedMax - Return the largest unsigned value contained in the
/// ConstantRange.
///
@@ -414,7 +430,7 @@
if (CR.Upper.ule(Lower))
return ConstantRange(CR.Lower, Upper);
- if (getSetSize().ult(CR.getSetSize()))
+ if (isSizeStrictlySmallerThanOf(CR))
return *this;
return CR;
}
@@ -429,7 +445,7 @@
if (CR.Upper.ult(Upper)) {
if (CR.Lower.ult(Upper)) {
- if (getSetSize().ult(CR.getSetSize()))
+ if (isSizeStrictlySmallerThanOf(CR))
return *this;
return CR;
}
@@ -445,7 +461,7 @@
return ConstantRange(CR.Lower, Upper);
}
- if (getSetSize().ult(CR.getSetSize()))
+ if (isSizeStrictlySmallerThanOf(CR))
return *this;
return CR;
}
@@ -739,17 +755,16 @@
if (isFullSet() || Other.isFullSet())
return ConstantRange(getBitWidth(), /*isFullSet=*/true);
- APInt Spread_X = getSetSize(), Spread_Y = Other.getSetSize();
APInt NewLower = getLower() + Other.getLower();
APInt NewUpper = getUpper() + Other.getUpper() - 1;
if (NewLower == NewUpper)
return ConstantRange(getBitWidth(), /*isFullSet=*/true);
ConstantRange X = ConstantRange(NewLower, NewUpper);
- if (X.getSetSize().ult(Spread_X) || X.getSetSize().ult(Spread_Y))
+ if (X.isSizeStrictlySmallerThanOf(*this) ||
+ X.isSizeStrictlySmallerThanOf(Other))
// We've wrapped, therefore, full set.
return ConstantRange(getBitWidth(), /*isFullSet=*/true);
-
return X;
}
@@ -773,17 +788,16 @@
if (isFullSet() || Other.isFullSet())
return ConstantRange(getBitWidth(), /*isFullSet=*/true);
- APInt Spread_X = getSetSize(), Spread_Y = Other.getSetSize();
APInt NewLower = getLower() - Other.getUpper() + 1;
APInt NewUpper = getUpper() - Other.getLower();
if (NewLower == NewUpper)
return ConstantRange(getBitWidth(), /*isFullSet=*/true);
ConstantRange X = ConstantRange(NewLower, NewUpper);
- if (X.getSetSize().ult(Spread_X) || X.getSetSize().ult(Spread_Y))
+ if (X.isSizeStrictlySmallerThanOf(*this) ||
+ X.isSizeStrictlySmallerThanOf(Other))
// We've wrapped, therefore, full set.
return ConstantRange(getBitWidth(), /*isFullSet=*/true);
-
return X;
}
@@ -837,7 +851,7 @@
ConstantRange Result_sext(std::min(L, Compare), std::max(L, Compare) + 1);
ConstantRange SR = Result_sext.truncate(getBitWidth());
- return UR.getSetSize().ult(SR.getSetSize()) ? UR : SR;
+ return UR.isSizeStrictlySmallerThanOf(SR) ? UR : SR;
}
ConstantRange