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-rw-r--r--compiler/optimizing/code_generator_mips.cc125
1 files changed, 31 insertions, 94 deletions
diff --git a/compiler/optimizing/code_generator_mips.cc b/compiler/optimizing/code_generator_mips.cc
index fdfa4eedf8..503026e399 100644
--- a/compiler/optimizing/code_generator_mips.cc
+++ b/compiler/optimizing/code_generator_mips.cc
@@ -8415,6 +8415,23 @@ void InstructionCodeGeneratorMIPS::VisitTypeConversion(HTypeConversion* conversi
}
} else if (Primitive::IsIntegralType(result_type) && Primitive::IsFloatingPointType(input_type)) {
CHECK(result_type == Primitive::kPrimInt || result_type == Primitive::kPrimLong);
+
+ // When NAN2008=1 (R6), the truncate instruction caps the output at the minimum/maximum
+ // value of the output type if the input is outside of the range after the truncation or
+ // produces 0 when the input is a NaN. IOW, the three special cases produce three distinct
+ // results. This matches the desired float/double-to-int/long conversion exactly.
+ //
+ // When NAN2008=0 (R2 and before), the truncate instruction produces the maximum positive
+ // value when the input is either a NaN or is outside of the range of the output type
+ // after the truncation. IOW, the three special cases (NaN, too small, too big) produce
+ // the same result.
+ //
+ // The code takes care of the different behaviors by first comparing the input to the
+ // minimum output value (-2**-63 for truncating to long, -2**-31 for truncating to int).
+ // If the input is greater than or equal to the minimum, it procedes to the truncate
+ // instruction, which will handle such an input the same way irrespective of NAN2008.
+ // Otherwise the input is compared to itself to determine whether it is a NaN or not
+ // in order to return either zero or the minimum value.
if (result_type == Primitive::kPrimLong) {
if (isR6) {
// trunc.l.s/trunc.l.d requires MIPSR2+ with FR=1. MIPS32R6 is implemented as a secondary
@@ -8422,62 +8439,6 @@ void InstructionCodeGeneratorMIPS::VisitTypeConversion(HTypeConversion* conversi
FRegister src = locations->InAt(0).AsFpuRegister<FRegister>();
Register dst_high = locations->Out().AsRegisterPairHigh<Register>();
Register dst_low = locations->Out().AsRegisterPairLow<Register>();
- MipsLabel truncate;
- MipsLabel done;
-
- // When NAN2008=0 (R2 and before), the truncate instruction produces the maximum positive
- // value when the input is either a NaN or is outside of the range of the output type
- // after the truncation. IOW, the three special cases (NaN, too small, too big) produce
- // the same result.
- //
- // When NAN2008=1 (R6), the truncate instruction caps the output at the minimum/maximum
- // value of the output type if the input is outside of the range after the truncation or
- // produces 0 when the input is a NaN. IOW, the three special cases produce three distinct
- // results. This matches the desired float/double-to-int/long conversion exactly.
- //
- // So, NAN2008 affects handling of negative values and NaNs by the truncate instruction.
- //
- // The following code supports both NAN2008=0 and NAN2008=1 behaviors of the truncate
- // instruction, the reason being that the emulator implements NAN2008=0 on MIPS64R6,
- // even though it must be NAN2008=1 on R6.
- //
- // The code takes care of the different behaviors by first comparing the input to the
- // minimum output value (-2**-63 for truncating to long, -2**-31 for truncating to int).
- // If the input is greater than or equal to the minimum, it procedes to the truncate
- // instruction, which will handle such an input the same way irrespective of NAN2008.
- // Otherwise the input is compared to itself to determine whether it is a NaN or not
- // in order to return either zero or the minimum value.
- //
- // TODO: simplify this when the emulator correctly implements NAN2008=1 behavior of the
- // truncate instruction for MIPS64R6.
- if (input_type == Primitive::kPrimFloat) {
- uint32_t min_val = bit_cast<uint32_t, float>(std::numeric_limits<int64_t>::min());
- __ LoadConst32(TMP, min_val);
- __ Mtc1(TMP, FTMP);
- __ CmpLeS(FTMP, FTMP, src);
- } else {
- uint64_t min_val = bit_cast<uint64_t, double>(std::numeric_limits<int64_t>::min());
- __ LoadConst32(TMP, High32Bits(min_val));
- __ Mtc1(ZERO, FTMP);
- __ Mthc1(TMP, FTMP);
- __ CmpLeD(FTMP, FTMP, src);
- }
-
- __ Bc1nez(FTMP, &truncate);
-
- if (input_type == Primitive::kPrimFloat) {
- __ CmpEqS(FTMP, src, src);
- } else {
- __ CmpEqD(FTMP, src, src);
- }
- __ Move(dst_low, ZERO);
- __ LoadConst32(dst_high, std::numeric_limits<int32_t>::min());
- __ Mfc1(TMP, FTMP);
- __ And(dst_high, dst_high, TMP);
-
- __ B(&done);
-
- __ Bind(&truncate);
if (input_type == Primitive::kPrimFloat) {
__ TruncLS(FTMP, src);
@@ -8486,8 +8447,6 @@ void InstructionCodeGeneratorMIPS::VisitTypeConversion(HTypeConversion* conversi
}
__ Mfc1(dst_low, FTMP);
__ Mfhc1(dst_high, FTMP);
-
- __ Bind(&done);
} else {
QuickEntrypointEnum entrypoint = (input_type == Primitive::kPrimFloat) ? kQuickF2l
: kQuickD2l;
@@ -8504,43 +8463,19 @@ void InstructionCodeGeneratorMIPS::VisitTypeConversion(HTypeConversion* conversi
MipsLabel truncate;
MipsLabel done;
- // The following code supports both NAN2008=0 and NAN2008=1 behaviors of the truncate
- // instruction, the reason being that the emulator implements NAN2008=0 on MIPS64R6,
- // even though it must be NAN2008=1 on R6.
- //
- // For details see the large comment above for the truncation of float/double to long on R6.
- //
- // TODO: simplify this when the emulator correctly implements NAN2008=1 behavior of the
- // truncate instruction for MIPS64R6.
- if (input_type == Primitive::kPrimFloat) {
- uint32_t min_val = bit_cast<uint32_t, float>(std::numeric_limits<int32_t>::min());
- __ LoadConst32(TMP, min_val);
- __ Mtc1(TMP, FTMP);
- } else {
- uint64_t min_val = bit_cast<uint64_t, double>(std::numeric_limits<int32_t>::min());
- __ LoadConst32(TMP, High32Bits(min_val));
- __ Mtc1(ZERO, FTMP);
- __ MoveToFpuHigh(TMP, FTMP);
- }
-
- if (isR6) {
+ if (!isR6) {
if (input_type == Primitive::kPrimFloat) {
- __ CmpLeS(FTMP, FTMP, src);
+ uint32_t min_val = bit_cast<uint32_t, float>(std::numeric_limits<int32_t>::min());
+ __ LoadConst32(TMP, min_val);
+ __ Mtc1(TMP, FTMP);
} else {
- __ CmpLeD(FTMP, FTMP, src);
+ uint64_t min_val = bit_cast<uint64_t, double>(std::numeric_limits<int32_t>::min());
+ __ LoadConst32(TMP, High32Bits(min_val));
+ __ Mtc1(ZERO, FTMP);
+ __ MoveToFpuHigh(TMP, FTMP);
}
- __ Bc1nez(FTMP, &truncate);
if (input_type == Primitive::kPrimFloat) {
- __ CmpEqS(FTMP, src, src);
- } else {
- __ CmpEqD(FTMP, src, src);
- }
- __ LoadConst32(dst, std::numeric_limits<int32_t>::min());
- __ Mfc1(TMP, FTMP);
- __ And(dst, dst, TMP);
- } else {
- if (input_type == Primitive::kPrimFloat) {
__ ColeS(0, FTMP, src);
} else {
__ ColeD(0, FTMP, src);
@@ -8554,11 +8489,11 @@ void InstructionCodeGeneratorMIPS::VisitTypeConversion(HTypeConversion* conversi
}
__ LoadConst32(dst, std::numeric_limits<int32_t>::min());
__ Movf(dst, ZERO, 0);
- }
- __ B(&done);
+ __ B(&done);
- __ Bind(&truncate);
+ __ Bind(&truncate);
+ }
if (input_type == Primitive::kPrimFloat) {
__ TruncWS(FTMP, src);
@@ -8567,7 +8502,9 @@ void InstructionCodeGeneratorMIPS::VisitTypeConversion(HTypeConversion* conversi
}
__ Mfc1(dst, FTMP);
- __ Bind(&done);
+ if (!isR6) {
+ __ Bind(&done);
+ }
}
} else if (Primitive::IsFloatingPointType(result_type) &&
Primitive::IsFloatingPointType(input_type)) {
generated by cgit v1.2.3 (git 2.25.1) at 2025-10-04 12:53:33 +0000