[GlobalISel] Translate floating-point negation
Reviewers: qcolombet, javed.absar, aditya_nandakumar, dsanders, t.p.northover, ab
Reviewed By: qcolombet
Subscribers: dberris, rovka, llvm-commits, kristof.beyls
Differential Revision: https://reviews.llvm.org/D30671
llvm-svn: 297171
diff --git a/llvm/lib/CodeGen/GlobalISel/IRTranslator.cpp b/llvm/lib/CodeGen/GlobalISel/IRTranslator.cpp
index 0470b3a..7033305 100644
--- a/llvm/lib/CodeGen/GlobalISel/IRTranslator.cpp
+++ b/llvm/lib/CodeGen/GlobalISel/IRTranslator.cpp
@@ -171,6 +171,18 @@
return true;
}
+bool IRTranslator::translateFSub(const User &U, MachineIRBuilder &MIRBuilder) {
+ // -0.0 - X --> G_FNEG
+ if (isa<Constant>(U.getOperand(0)) &&
+ U.getOperand(0) == ConstantFP::getZeroValueForNegation(U.getType())) {
+ MIRBuilder.buildInstr(TargetOpcode::G_FNEG)
+ .addDef(getOrCreateVReg(U))
+ .addUse(getOrCreateVReg(*U.getOperand(1)));
+ return true;
+ }
+ return translateBinaryOp(TargetOpcode::G_FSUB, U, MIRBuilder);
+}
+
bool IRTranslator::translateCompare(const User &U,
MachineIRBuilder &MIRBuilder) {
const CmpInst *CI = dyn_cast<CmpInst>(&U);