AArch64: improve usage of TargetReg() and friends.
TargetReg(arg1) does now always return a 32-bit register. We also avoid
using this function directly and rather use the two-arguments overload
or TargetPtrReg().
Change-Id: I746b3c29a2a2553b399b5c3e7ee3887c7e7c52c3
diff --git a/compiler/dex/quick/arm64/assemble_arm64.cc b/compiler/dex/quick/arm64/assemble_arm64.cc
index 083277d..462be54 100644
--- a/compiler/dex/quick/arm64/assemble_arm64.cc
+++ b/compiler/dex/quick/arm64/assemble_arm64.cc
@@ -655,10 +655,10 @@
if (kIsDebugBuild && (kFailOnSizeError || kReportSizeError)) {
// Register usage checks: First establish register usage requirements based on the
// format in `kind'.
- bool want_float = false;
- bool want_64_bit = false;
- bool want_var_size = true;
- bool want_zero = false;
+ bool want_float = false; // Want a float (rather than core) register.
+ bool want_64_bit = false; // Want a 64-bit (rather than 32-bit) register.
+ bool want_var_size = true; // Want register with variable size (kFmtReg{R,F}).
+ bool want_zero = false; // Want the zero (rather than sp) register.
switch (kind) {
case kFmtRegX:
want_64_bit = true;
@@ -717,9 +717,6 @@
}
}
- // TODO(Arm64): if !want_size_match, then we still should compare the size of the
- // register with the size required by the instruction width (kA64Wide).
-
// Fail, if `expected' contains an unsatisfied requirement.
if (expected != nullptr) {
LOG(WARNING) << "Method: " << PrettyMethod(cu_->method_idx, *cu_->dex_file)
@@ -734,11 +731,12 @@
}
}
- // TODO(Arm64): this may or may not be necessary, depending on how wzr, xzr are
- // defined.
- if (is_zero) {
- operand = 31;
- }
+ // In the lines below, we rely on (operand & 0x1f) == 31 to be true for register sp
+ // and zr. This means that these two registers do not need any special treatment, as
+ // their bottom 5 bits are correctly set to 31 == 0b11111, which is the right
+ // value for encoding both sp and zr.
+ COMPILE_ASSERT((rxzr & 0x1f) == 0x1f, rzr_register_number_must_be_31);
+ COMPILE_ASSERT((rsp & 0x1f) == 0x1f, rsp_register_number_must_be_31);
}
value = (operand << encoder->field_loc[i].start) &