[AArch64][GlobalISel] Legalize G_FEXP2

Same as G_EXP. Add a test, and update legalizer-info-validation.mir and
f16-instructions.ll.

Differential Revision: https://reviews.llvm.org/D60165

llvm-svn: 357605
diff --git a/llvm/lib/CodeGen/GlobalISel/LegalizerHelper.cpp b/llvm/lib/CodeGen/GlobalISel/LegalizerHelper.cpp
index 61b6bc5..46b56d3 100644
--- a/llvm/lib/CodeGen/GlobalISel/LegalizerHelper.cpp
+++ b/llvm/lib/CodeGen/GlobalISel/LegalizerHelper.cpp
@@ -244,6 +244,9 @@
   case TargetOpcode::G_FEXP:
     assert((Size == 32 || Size == 64) && "Unsupported size");
     return Size == 64 ? RTLIB::EXP_F64 : RTLIB::EXP_F32;
+  case TargetOpcode::G_FEXP2:
+    assert((Size == 32 || Size == 64) && "Unsupported size");
+    return Size == 64 ? RTLIB::EXP2_F64 : RTLIB::EXP2_F32;
   case TargetOpcode::G_FREM:
     return Size == 64 ? RTLIB::REM_F64 : RTLIB::REM_F32;
   case TargetOpcode::G_FPOW:
@@ -368,7 +371,8 @@
   case TargetOpcode::G_FLOG10:
   case TargetOpcode::G_FLOG:
   case TargetOpcode::G_FLOG2:
-  case TargetOpcode::G_FEXP: {
+  case TargetOpcode::G_FEXP:
+  case TargetOpcode::G_FEXP2: {
     if (Size > 64) {
       LLVM_DEBUG(dbgs() << "Size " << Size << " too large to legalize.\n");
       return UnableToLegalize;
@@ -1345,6 +1349,7 @@
   case TargetOpcode::G_FLOG2:
   case TargetOpcode::G_FSQRT:
   case TargetOpcode::G_FEXP:
+  case TargetOpcode::G_FEXP2:
     assert(TypeIdx == 0);
     Observer.changingInstr(MI);