From 4c7c0f23533565c7e2ddf71e01bf50f2aede5f1b Mon Sep 17 00:00:00 2001
From: Nadav Rotem <nadav.rotem@intel.com>
Date: Wed, 24 Aug 2011 20:18:38 +0000
Subject: [PATCH] Implement Constant::isAllOnesValue(). Fix ConstantFolding to
use the new api.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@138469 91177308-0d34-0410-b5e6-96231b3b80d8
---
include/llvm/Constant.h | 4 +++
include/llvm/Constants.h | 2 +-
lib/Analysis/ConstantFolding.cpp | 17 ++++++-------
lib/VMCore/Constants.cpp | 24 +++++++++++++++---
test/Transforms/InstCombine/bitcast.ll | 34 ++++++++++++++++++++++----
5 files changed, 62 insertions(+), 19 deletions(-)
diff --git a/include/llvm/Constant.h b/include/llvm/Constant.h
index 601b37bb64e..ecc1fe70cc5 100644
--- a/include/llvm/Constant.h
+++ b/include/llvm/Constant.h
@@ -52,6 +52,10 @@ public:
/// getNullValue.
bool isNullValue() const;
+ /// isAllOnesValue - Return true if this is the value that would be returned by
+ /// getAllOnesValue.
+ bool isAllOnesValue() const;
+
/// isNegativeZeroValue - Return true if the value is what would be returned
/// by getZeroValueForNegation.
bool isNegativeZeroValue() const;
diff --git a/include/llvm/Constants.h b/include/llvm/Constants.h
index 5785b8187d8..e168979beaa 100644
--- a/include/llvm/Constants.h
+++ b/include/llvm/Constants.h
@@ -170,7 +170,7 @@ public:
/// to true.
/// @returns true iff this constant's bits are all set to true.
/// @brief Determine if the value is all ones.
- bool isAllOnesValue() const {
+ bool isMinusOne() const {
return Val.isAllOnesValue();
}
diff --git a/lib/Analysis/ConstantFolding.cpp b/lib/Analysis/ConstantFolding.cpp
index 7a8c703040c..df79849c3cf 100644
--- a/lib/Analysis/ConstantFolding.cpp
+++ b/lib/Analysis/ConstantFolding.cpp
@@ -45,16 +45,12 @@ using namespace llvm;
/// ConstantExpr if unfoldable.
static Constant *FoldBitCast(Constant *C, Type *DestTy,
const TargetData &TD) {
-
- ConstantVector *CV = dyn_cast<ConstantVector>(C);
- IntegerType *IntVTy = dyn_cast<IntegerType>(DestTy);
- // When casting vectors to scalar integers, catch the
- // obvious splat cases.
- if (IntVTy && CV) {
- if (CV->isNullValue()) return ConstantInt::getNullValue(IntVTy);
- if (CV->isAllOnesValue()) return ConstantInt::getAllOnesValue(IntVTy);
- }
-
+ // Catch the obvious splat cases.
+ if (C->isNullValue() && !DestTy->isX86_MMXTy())
+ return Constant::getNullValue(DestTy);
+ if (C->isAllOnesValue() && !DestTy->isX86_MMXTy())
+ return Constant::getAllOnesValue(DestTy);
+
// The code below only handles casts to vectors currently.
VectorType *DestVTy = dyn_cast<VectorType>(DestTy);
if (DestVTy == 0)
@@ -68,6 +64,7 @@ static Constant *FoldBitCast(Constant *C, Type *DestTy,
}
// If this is a bitcast from constant vector -> vector, fold it.
+ ConstantVector *CV = dyn_cast<ConstantVector>(C);
if (CV == 0)
return ConstantExpr::getBitCast(C, DestTy);
diff --git a/lib/VMCore/Constants.cpp b/lib/VMCore/Constants.cpp
index 2f22cda5ba4..ba309d9ca07 100644
--- a/lib/VMCore/Constants.cpp
+++ b/lib/VMCore/Constants.cpp
@@ -62,6 +62,21 @@ bool Constant::isNullValue() const {
return isa<ConstantAggregateZero>(this) || isa<ConstantPointerNull>(this);
}
+bool Constant::isAllOnesValue() const {
+ // Check for -1 integers
+ if (const ConstantInt *CI = dyn_cast<ConstantInt>(this))
+ return CI->isMinusOne();
+
+ // Check for FP which are bitcasted from -1 integers
+ if (const ConstantFP *CFP = dyn_cast<ConstantFP>(this))
+ return CFP->getValueAPF().bitcastToAPInt().isAllOnesValue();
+
+ // Check for constant vectors
+ if (const ConstantVector *CV = dyn_cast<ConstantVector>(this))
+ return CV->isAllOnesValue();
+
+ return false;
+}
// Constructor to create a '0' constant of arbitrary type...
Constant *Constant::getNullValue(Type *Ty) {
switch (Ty->getTypeID()) {
@@ -126,7 +141,7 @@ Constant *Constant::getAllOnesValue(Type *Ty) {
SmallVector<Constant*, 16> Elts;
VectorType *VTy = cast<VectorType>(Ty);
Elts.resize(VTy->getNumElements(), getAllOnesValue(VTy->getElementType()));
- assert(Elts[0] && "Not a vector integer type!");
+ assert(Elts[0] && "Invalid AllOnes value!");
return cast<ConstantVector>(ConstantVector::get(Elts));
}
@@ -1064,13 +1079,16 @@ bool ConstantVector::isAllOnesValue() const {
// Check out first element.
const Constant *Elt = getOperand(0);
const ConstantInt *CI = dyn_cast<ConstantInt>(Elt);
- if (!CI || !CI->isAllOnesValue()) return false;
+ const ConstantFP *CF = dyn_cast<ConstantFP>(Elt);
+
// Then make sure all remaining elements point to the same value.
for (unsigned I = 1, E = getNumOperands(); I < E; ++I)
if (getOperand(I) != Elt)
return false;
- return true;
+ // First value is all-ones.
+ return (CI && CI->isAllOnesValue()) ||
+ (CF && CF->isAllOnesValue());
}
/// getSplatValue - If this is a splat constant, where all of the
diff --git a/test/Transforms/InstCombine/bitcast.ll b/test/Transforms/InstCombine/bitcast.ll
index 3458c7b95b4..8f6ae7d8352 100644
--- a/test/Transforms/InstCombine/bitcast.ll
+++ b/test/Transforms/InstCombine/bitcast.ll
@@ -11,7 +11,7 @@ define i32 @test1(i64 %a) {
%t3 = xor <2 x i32> %t1, %t2
%t4 = extractelement <2 x i32> %t3, i32 0
ret i32 %t4
-
+
; CHECK: @test1
; CHECK: ret i32 0
}
@@ -30,7 +30,7 @@ define float @test2(<2 x float> %A, <2 x i32> %B) {
%add = fadd float %tmp24, %tmp4
ret float %add
-
+
; CHECK: @test2
; CHECK-NEXT: %tmp24 = extractelement <2 x float> %A, i32 0
; CHECK-NEXT: bitcast <2 x i32> %B to <2 x float>
@@ -55,7 +55,7 @@ define float @test3(<2 x float> %A, <2 x i64> %B) {
%add = fadd float %tmp24, %tmp4
ret float %add
-
+
; CHECK: @test3
; CHECK-NEXT: %tmp24 = extractelement <2 x float> %A, i32 1
; CHECK-NEXT: bitcast <2 x i64> %B to <4 x float>
@@ -75,7 +75,7 @@ define <2 x i32> @test4(i32 %A, i32 %B){
; CHECK: @test4
; CHECK-NEXT: insertelement <2 x i32> undef, i32 %A, i32 0
; CHECK-NEXT: insertelement <2 x i32> {{.*}}, i32 %B, i32 1
- ; CHECK-NEXT: ret <2 x i32>
+ ; CHECK-NEXT: ret <2 x i32>
}
@@ -92,7 +92,7 @@ define <2 x float> @test5(float %A, float %B) {
; CHECK: @test5
; CHECK-NEXT: insertelement <2 x float> undef, float %A, i32 0
; CHECK-NEXT: insertelement <2 x float> {{.*}}, float %B, i32 1
- ; CHECK-NEXT: ret <2 x float>
+ ; CHECK-NEXT: ret <2 x float>
}
define <2 x float> @test6(float %A){
@@ -113,3 +113,27 @@ define i64 @ISPC0(i64 %in) {
; CHECK: @ISPC0
; CHECK: ret i64 0
}
+
+
+define i64 @Vec2(i64 %in) {
+ %out = and i64 %in, xor (i64 bitcast (<4 x i16> <i16 0, i16 0, i16 0, i16 0> to i64), i64 0)
+ ret i64 %out
+; CHECK: @Vec2
+; CHECK: ret i64 0
+}
+
+define i64 @All11(i64 %in) {
+ %out = and i64 %in, xor (i64 bitcast (<2 x float> bitcast (i64 -1 to <2 x float>) to i64), i64 -1)
+ ret i64 %out
+; CHECK: @All11
+; CHECK: ret i64 0
+}
+
+
+define i32 @All111(i32 %in) {
+ %out = and i32 %in, xor (i32 bitcast (<1 x float> bitcast (i32 -1 to <1 x float>) to i32), i32 -1)
+ ret i32 %out
+; CHECK: @All111
+; CHECK: ret i32 0
+}
+
--
2.34.1