Decompose FP-to-UInt casts into FP-to-ULong-toUInt.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@3957 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Target/SparcV9/SparcV9PreSelection.cpp b/lib/Target/SparcV9/SparcV9PreSelection.cpp
index 2e55594..e3dec46 100644
--- a/lib/Target/SparcV9/SparcV9PreSelection.cpp
+++ b/lib/Target/SparcV9/SparcV9PreSelection.cpp
@@ -146,6 +146,7 @@
void visitInstruction(Instruction &I); // common work for every instr.
void visitGetElementPtrInst(GetElementPtrInst &I);
void visitLoadInst(LoadInst &I);
+ void visitCastInst(CastInst &I);
void visitStoreInst(StoreInst &I);
// Helper functions for visiting operands of every instruction
@@ -228,6 +229,33 @@
}
+// Cast instructions: make multi-step casts explicit
+// -- float/double to uint32_t:
+// If target does not have a float-to-unsigned instruction, we
+// need to convert to uint64_t and then to uint32_t, or we may
+// overflow the signed int representation for legal uint32_t
+// values. Expand this without checking target.
+//
+void
+PreSelection::visitCastInst(CastInst &I)
+{
+ CastInst* castI = NULL;
+
+ // Check for a global and put its address into a register before this instr
+ if (I.getType() == Type::UIntTy &&
+ I.getOperand(0)->getType()->isFloatingPoint())
+ { // insert a cast-fp-to-long before I, and then replace the operand of I
+ castI = new CastInst(I.getOperand(0), Type::LongTy, "fp2Long2Uint", &I);
+ I.setOperand(0, castI); // replace fp operand with long
+ }
+
+ // Perform other transformations common to all instructions
+ visitInstruction(I);
+ if (castI)
+ visitInstruction(*castI);
+}
+
+
// visitOperands() transforms individual operands of all instructions:
// -- Load "large" int constants into a virtual register. What is large
// depends on the type of instruction and on the target architecture.