GlobalISel: Add LLT helper to multiply vector sizes

[arsenm]

ping

[paquette]

llvm/include/llvm/Support/LowLevelTypeImpl.h

213

why int?

[arsenm]

llvm/include/llvm/Support/LowLevelTypeImpl.h

213

Copy paste from the above divide. Plus I'm generally of the belief that using unsigned is bad, but basically everywhere else uses unsigned

[paquette]

LGTM

llvm/include/llvm/Support/LowLevelTypeImpl.h

213

that's like the opposite of my personal belief

[arsenm]

12d79b1514b8036a6079495a45091c9bfb8db1a6

llvm/include/llvm/Support/LowLevelTypeImpl.h

if (isVector()) {
       return scalarOrVector(getElementCount().divideCoefficientBy(Factor),
                             getElementType());
     }
 
     assert(getScalarSizeInBits() % Factor == 0);
     return scalar(getScalarSizeInBits() / Factor);
   }
 
+  /// Produce a vector type that is \p Factor times bigger, preserving the
+  /// element type. For a scalar or pointer, this will produce a new vector with
+  /// \p Factor elements.
+  LLT multiplyElements(int Factor) const {
+    if (isVector()) {
+      return scalarOrVector(getElementCount().multiplyCoefficientBy(Factor),
+                            getElementType());
+    }
+
+    return fixed_vector(Factor, *this);
+  }
+
   bool isByteSized() const { return getSizeInBits().isKnownMultipleOf(8); }
 
   unsigned getScalarSizeInBits() const {
     if (IsScalar)
       return getFieldValue(ScalarSizeFieldInfo);
     if (IsVector) {
       if (!IsPointer)
         return getFieldValue(VectorSizeFieldInfo);

llvm/include/llvm/Support/TypeSize.h

public:
   /// The caller is recommended to use this function in combination with
   /// isKnownMultipleOf(RHS), which lets the caller know if it's possible to
   /// perform a lossless divide by RHS.
   LeafTy divideCoefficientBy(ScalarTy RHS) const {
     return static_cast<LeafTy>(
         LinearPolySize::get(getKnownMinValue() / RHS, isScalable()));
   }
 
+  LeafTy multiplyCoefficientBy(ScalarTy RHS) const {
+    return static_cast<LeafTy>(
+        LinearPolySize::get(getKnownMinValue() * RHS, isScalable()));
+  }
+
   LeafTy coefficientNextPowerOf2() const {
     return static_cast<LeafTy>(LinearPolySize::get(
         static_cast<ScalarTy>(llvm::NextPowerOf2(getKnownMinValue())),
         isScalable()));
   }
 
   /// Printing function.
   void print(raw_ostream &OS) const {

llvm/unittests/CodeGen/LowLevelTypeTest.cpp

TEST(LowLevelTypeTest, Divide) {
 
   // Test vector of pointers
   EXPECT_EQ(LLT::pointer(1, 64),
             LLT::fixed_vector(4, LLT::pointer(1, 64)).divide(4));
   EXPECT_EQ(LLT::fixed_vector(2, LLT::pointer(1, 64)),
             LLT::fixed_vector(4, LLT::pointer(1, 64)).divide(2));
 }
 
+TEST(LowLevelTypeTest, MultiplyElements) {
+  // Basic scalar->vector cases
+  EXPECT_EQ(LLT::fixed_vector(2, 16), LLT::scalar(16).multiplyElements(2));
+  EXPECT_EQ(LLT::fixed_vector(3, 16), LLT::scalar(16).multiplyElements(3));
+  EXPECT_EQ(LLT::fixed_vector(4, 32), LLT::scalar(32).multiplyElements(4));
+  EXPECT_EQ(LLT::fixed_vector(4, 7), LLT::scalar(7).multiplyElements(4));
+
+  // Basic vector to vector cases
+  EXPECT_EQ(LLT::fixed_vector(4, 32),
+            LLT::fixed_vector(2, 32).multiplyElements(2));
+  EXPECT_EQ(LLT::fixed_vector(9, 32),
+            LLT::fixed_vector(3, 32).multiplyElements(3));
+
+  // Pointer to vector of pointers
+  EXPECT_EQ(LLT::fixed_vector(2, LLT::pointer(0, 32)),
+            LLT::pointer(0, 32).multiplyElements(2));
+  EXPECT_EQ(LLT::fixed_vector(3, LLT::pointer(1, 32)),
+            LLT::pointer(1, 32).multiplyElements(3));
+  EXPECT_EQ(LLT::fixed_vector(4, LLT::pointer(1, 64)),
+            LLT::pointer(1, 64).multiplyElements(4));
+
+  // Vector of pointers to vector of pointers
+  EXPECT_EQ(LLT::fixed_vector(8, LLT::pointer(1, 64)),
+            LLT::fixed_vector(2, LLT::pointer(1, 64)).multiplyElements(4));
+  EXPECT_EQ(LLT::fixed_vector(9, LLT::pointer(1, 32)),
+            LLT::fixed_vector(3, LLT::pointer(1, 32)).multiplyElements(3));
+
+  // Scalable vectors
+  EXPECT_EQ(LLT::scalable_vector(4, 16),
+            LLT::scalable_vector(2, 16).multiplyElements(2));
+  EXPECT_EQ(LLT::scalable_vector(6, 16),
+            LLT::scalable_vector(2, 16).multiplyElements(3));
+  EXPECT_EQ(LLT::scalable_vector(9, 16),
+            LLT::scalable_vector(3, 16).multiplyElements(3));
+  EXPECT_EQ(LLT::scalable_vector(4, 32),
+            LLT::scalable_vector(2, 32).multiplyElements(2));
+  EXPECT_EQ(LLT::scalable_vector(256, 32),
+            LLT::scalable_vector(8, 32).multiplyElements(32));
+
+  // Scalable vectors of pointers
+  EXPECT_EQ(LLT::scalable_vector(4, LLT::pointer(0, 32)),
+            LLT::scalable_vector(2, LLT::pointer(0, 32)).multiplyElements(2));
+  EXPECT_EQ(LLT::scalable_vector(32, LLT::pointer(1, 64)),
+            LLT::scalable_vector(8, LLT::pointer(1, 64)).multiplyElements(4));
+}
 }