[GlobalISel] Avoid repeated hash lookups (NFC)

Author: kazutakahirata

llvm/include/llvm/CodeGen/GlobalISel/LegacyLegalizerInfo.h

@@ -318,11 +318,8 @@ class LegacyLegalizerInfo {
                         const unsigned AddressSpace,
                         const SizeAndActionsVec &SizeAndActions) {
     const unsigned OpcodeIdx = Opcode - FirstOp;
-    if (AddrSpace2PointerActions[OpcodeIdx].find(AddressSpace) ==
-        AddrSpace2PointerActions[OpcodeIdx].end())
-      AddrSpace2PointerActions[OpcodeIdx][AddressSpace] = {{}};
     SmallVector<SizeAndActionsVec, 1> &Actions =
-        AddrSpace2PointerActions[OpcodeIdx].find(AddressSpace)->second;
+        AddrSpace2PointerActions[OpcodeIdx][AddressSpace];
     setActions(TypeIndex, Actions, SizeAndActions);
   }
 
@@ -347,11 +344,8 @@ class LegacyLegalizerInfo {
                                  const unsigned ElementSize,
                                  const SizeAndActionsVec &SizeAndActions) {
     const unsigned OpcodeIdx = Opcode - FirstOp;
-    if (NumElements2Actions[OpcodeIdx].find(ElementSize) ==
-        NumElements2Actions[OpcodeIdx].end())
-      NumElements2Actions[OpcodeIdx][ElementSize] = {{}};
     SmallVector<SizeAndActionsVec, 1> &Actions =
-        NumElements2Actions[OpcodeIdx].find(ElementSize)->second;
+        NumElements2Actions[OpcodeIdx][ElementSize];
     setActions(TypeIndex, Actions, SizeAndActions);
   }