Quick compiler: fix x86 special identity
The Quick compiler recognizes and specially handles a set of
small methods - including those that simply return one of their
arguments. For x86, special identity was broken if the returned
argument was a double that was passed half in register and half
in memory.
internal b/17325447
Change-Id: I3a766977cdc0b4216d8ad65a9870c3250b32471e
diff --git a/compiler/dex/quick/mir_to_lir.cc b/compiler/dex/quick/mir_to_lir.cc
index c945f7f..70ef991 100644
--- a/compiler/dex/quick/mir_to_lir.cc
+++ b/compiler/dex/quick/mir_to_lir.cc
@@ -201,6 +201,16 @@
RegStorage reg_arg_low = GetArgMappingToPhysicalReg(in_position);
RegStorage reg_arg_high = GetArgMappingToPhysicalReg(in_position + 1);
+ if (cu_->instruction_set == kX86) {
+ // Can't handle double split between reg & memory. Flush reg half to memory.
+ if (rl_dest.reg.IsDouble() && (reg_arg_low.Valid() != reg_arg_high.Valid())) {
+ DCHECK(reg_arg_low.Valid());
+ DCHECK(!reg_arg_high.Valid());
+ Store32Disp(TargetPtrReg(kSp), offset, reg_arg_low);
+ reg_arg_low = RegStorage::InvalidReg();
+ }
+ }
+
if (reg_arg_low.Valid() && reg_arg_high.Valid()) {
OpRegCopyWide(rl_dest.reg, RegStorage::MakeRegPair(reg_arg_low, reg_arg_high));
} else if (reg_arg_low.Valid() && !reg_arg_high.Valid()) {