utils: optimize PerMachine

There is no need to create and look up a dictionary when MachineChoice is
an enum, and there is no need to create a PerMachine object on every
__setitem__ of another PerMachine object.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

1 files changed, 7 insertions, 6 deletions

diff --git a/mesonbuild/utils/universal.py b/mesonbuild/utils/universal.py
index 76a6df8da..8012dcee3 100644
--- a/mesonbuild/utils/universal.py
+++ b/mesonbuild/utils/universal.py
@@ -473,6 +473,10 @@ def classify_unity_sources(compilers: T.Iterable['Compiler'], sources: T.Sequenc
     return compsrclist
 
 
+MACHINE_NAMES = ['build', 'host']
+MACHINE_PREFIXES = ['build.', '']
+
+
 class MachineChoice(enum.IntEnum):
 
     """Enum class representing one of the two abstract machine names used in
@@ -486,10 +490,10 @@ class MachineChoice(enum.IntEnum):
         return f'{self.get_lower_case_name()} machine'
 
     def get_lower_case_name(self) -> str:
-        return PerMachine('build', 'host')[self]
+        return MACHINE_NAMES[self.value]
 
     def get_prefix(self) -> str:
-        return PerMachine('build.', '')[self]
+        return MACHINE_PREFIXES[self.value]
 
 
 class PerMachine(T.Generic[_T]):
@@ -498,10 +502,7 @@ class PerMachine(T.Generic[_T]):
         self.host = host
 
     def __getitem__(self, machine: MachineChoice) -> _T:
-        return {
-            MachineChoice.BUILD:  self.build,
-            MachineChoice.HOST:   self.host,
-        }[machine]
+        return [self.build, self.host][machine.value]
 
     def __setitem__(self, machine: MachineChoice, val: _T) -> None:
         setattr(self, machine.get_lower_case_name(), val)