[optimizing] Fold HTypeConversion of constants
While looking into optimizing long shifts on x86, I found that the
compiler wasn't folding HTypeConversion of constants. Add simple
conversions of constants, taking care of float/double values
with NaNs and small/large values, ensuring Java conversion semantics.
Add checker cases to see that constant folding of HTypeConversion is
done.
Ensure 422-type-conversion type conversion routiness don't get
inlined to avoid compile time folding.
Change-Id: I5a4eb376b64bc4e41bf908af5875bed312efb228
Signed-off-by: Mark Mendell <mark.p.mendell@intel.com>
diff --git a/compiler/optimizing/constant_folding.cc b/compiler/optimizing/constant_folding.cc
index 5a1d9b4..20ce110 100644
--- a/compiler/optimizing/constant_folding.cc
+++ b/compiler/optimizing/constant_folding.cc
@@ -71,6 +71,14 @@
inst->ReplaceWith(constant);
inst->GetBlock()->RemoveInstruction(inst);
}
+ } else if (inst->IsTypeConversion()) {
+ // Constant folding: replace `TypeConversion(a)' with a constant at
+ // compile time if `a' is a constant.
+ HConstant* constant = inst->AsTypeConversion()->TryStaticEvaluation();
+ if (constant != nullptr) {
+ inst->ReplaceWith(constant);
+ inst->GetBlock()->RemoveInstruction(inst);
+ }
} else if (inst->IsDivZeroCheck()) {
// We can safely remove the check if the input is a non-null constant.
HDivZeroCheck* check = inst->AsDivZeroCheck();