Chromium Code Reviews
chromiumcodereview-hr@appspot.gserviceaccount.com (chromiumcodereview-hr) | Please choose your nickname with Settings | Help | Chromium Project | Gerrit Changes | Sign out
(268)

Issues Search
    My Issues | Starred     Open | Closed | All

Unified Diff: src/mips/code-stubs-mips.cc

Issue 11308158: MIPS: Fix register confusion in non-VFP3 BinaryOpStubs on ARM (Closed) Base URL: https://v8.googlecode.com/svn/branches/bleeding_edge
Patch Set: Rebased on r13080 Created 8 years, 1 month ago
Use n/p to move between diff chunks; N/P to move between comments. Draft comments are only viewable by you.
Jump to:
View side-by-side diff with in-line comments
Download patch
« no previous file with comments | « no previous file | src/mips/stub-cache-mips.cc » ('j') | no next file with comments »
Expand Comments ('e') | Collapse Comments ('c') | Show Comments Hide Comments ('s')
Index: src/mips/code-stubs-mips.cc
diff --git a/src/mips/code-stubs-mips.cc b/src/mips/code-stubs-mips.cc
index aa27f6abe9f9df5f3e7f87b769f2a5af34845e65..a05cee86bb1cf175c9e697672a8a40743c1b1dd3 100644
--- a/src/mips/code-stubs-mips.cc
+++ b/src/mips/code-stubs-mips.cc
@@ -734,13 +734,13 @@ void FloatingPointHelper::ConvertIntToDouble(MacroAssembler* masm,
Register int_scratch,
Destination destination,
FPURegister double_dst,
- Register dst1,
- Register dst2,
+ Register dst_mantissa,
+ Register dst_exponent,
Register scratch2,
FPURegister single_scratch) {
ASSERT(!int_scratch.is(scratch2));
- ASSERT(!int_scratch.is(dst1));
- ASSERT(!int_scratch.is(dst2));
+ ASSERT(!int_scratch.is(dst_mantissa));
+ ASSERT(!int_scratch.is(dst_exponent));
Label done;
@@ -749,64 +749,65 @@ void FloatingPointHelper::ConvertIntToDouble(MacroAssembler* masm,
__ mtc1(int_scratch, single_scratch);
__ cvt_d_w(double_dst, single_scratch);
if (destination == kCoreRegisters) {
- __ Move(dst1, dst2, double_dst);
+ __ Move(dst_mantissa, dst_exponent, double_dst);
}
} else {
Label fewer_than_20_useful_bits;
// Expected output:
- // | dst2 | dst1 |
+ // | dst_exponent | dst_mantissa |
// | s | exp | mantissa |
// Check for zero.
- __ mov(dst2, int_scratch);
- __ mov(dst1, int_scratch);
+ __ mov(dst_exponent, int_scratch);
+ __ mov(dst_mantissa, int_scratch);
__ Branch(&done, eq, int_scratch, Operand(zero_reg));
// Preload the sign of the value.
- __ And(dst2, int_scratch, Operand(HeapNumber::kSignMask));
+ __ And(dst_exponent, int_scratch, Operand(HeapNumber::kSignMask));
// Get the absolute value of the object (as an unsigned integer).
Label skip_sub;
- __ Branch(&skip_sub, ge, dst2, Operand(zero_reg));
+ __ Branch(&skip_sub, ge, dst_exponent, Operand(zero_reg));
__ Subu(int_scratch, zero_reg, int_scratch);
__ bind(&skip_sub);
// Get mantissa[51:20].
// Get the position of the first set bit.
- __ Clz(dst1, int_scratch);
+ __ Clz(dst_mantissa, int_scratch);
__ li(scratch2, 31);
- __ Subu(dst1, scratch2, dst1);
+ __ Subu(dst_mantissa, scratch2, dst_mantissa);
// Set the exponent.
- __ Addu(scratch2, dst1, Operand(HeapNumber::kExponentBias));
- __ Ins(dst2, scratch2,
+ __ Addu(scratch2, dst_mantissa, Operand(HeapNumber::kExponentBias));
+ __ Ins(dst_exponent, scratch2,
HeapNumber::kExponentShift, HeapNumber::kExponentBits);
// Clear the first non null bit.
__ li(scratch2, Operand(1));
- __ sllv(scratch2, scratch2, dst1);
+ __ sllv(scratch2, scratch2, dst_mantissa);
__ li(at, -1);
__ Xor(scratch2, scratch2, at);
__ And(int_scratch, int_scratch, scratch2);
// Get the number of bits to set in the lower part of the mantissa.
- __ Subu(scratch2, dst1, Operand(HeapNumber::kMantissaBitsInTopWord));
+ __ Subu(scratch2, dst_mantissa,
+ Operand(HeapNumber::kMantissaBitsInTopWord));
__ Branch(&fewer_than_20_useful_bits, lt, scratch2, Operand(zero_reg));
// Set the higher 20 bits of the mantissa.
__ srlv(at, int_scratch, scratch2);
- __ or_(dst2, dst2, at);
+ __ or_(dst_exponent, dst_exponent, at);
__ li(at, 32);
__ subu(scratch2, at, scratch2);
- __ sllv(dst1, int_scratch, scratch2);
+ __ sllv(dst_mantissa, int_scratch, scratch2);
__ Branch(&done);
__ bind(&fewer_than_20_useful_bits);
__ li(at, HeapNumber::kMantissaBitsInTopWord);
- __ subu(scratch2, at, dst1);
+ __ subu(scratch2, at, dst_mantissa);
__ sllv(scratch2, int_scratch, scratch2);
- __ Or(dst2, dst2, scratch2);
- // Set dst1 to 0.
- __ mov(dst1, zero_reg);
+ __ Or(dst_exponent, dst_exponent, scratch2);
+ // Set dst_mantissa to 0.
+ __ mov(dst_mantissa, zero_reg);
}
__ bind(&done);
}
@@ -817,8 +818,8 @@ void FloatingPointHelper::LoadNumberAsInt32Double(MacroAssembler* masm,
Destination destination,
DoubleRegister double_dst,
DoubleRegister double_scratch,
- Register dst1,
- Register dst2,
+ Register dst_mantissa,
+ Register dst_exponent,
Register heap_number_map,
Register scratch1,
Register scratch2,
@@ -834,8 +835,8 @@ void FloatingPointHelper::LoadNumberAsInt32Double(MacroAssembler* masm,
__ JumpIfNotSmi(object, &obj_is_not_smi);
__ SmiUntag(scratch1, object);
- ConvertIntToDouble(masm, scratch1, destination, double_dst, dst1, dst2,
- scratch2, single_scratch);
+ ConvertIntToDouble(masm, scratch1, destination, double_dst, dst_mantissa,
+ dst_exponent, scratch2, single_scratch);
__ Branch(&done);
__ bind(&obj_is_not_smi);
@@ -863,27 +864,51 @@ void FloatingPointHelper::LoadNumberAsInt32Double(MacroAssembler* masm,
__ Branch(not_int32, ne, except_flag, Operand(zero_reg));
if (destination == kCoreRegisters) {
- __ Move(dst1, dst2, double_dst);
+ __ Move(dst_mantissa, dst_exponent, double_dst);
}
} else {
ASSERT(!scratch1.is(object) && !scratch2.is(object));
// Load the double value in the destination registers.
- __ lw(dst2, FieldMemOperand(object, HeapNumber::kExponentOffset));
- __ lw(dst1, FieldMemOperand(object, HeapNumber::kMantissaOffset));
+ bool save_registers = object.is(dst_mantissa) || object.is(dst_exponent);
+ if (save_registers) {
+ // Save both output registers, because the other one probably holds
+ // an important value too.
+ __ Push(dst_exponent, dst_mantissa);
+ }
+ __ lw(dst_exponent, FieldMemOperand(object, HeapNumber::kExponentOffset));
+ __ lw(dst_mantissa, FieldMemOperand(object, HeapNumber::kMantissaOffset));
// Check for 0 and -0.
- __ And(scratch1, dst1, Operand(~HeapNumber::kSignMask));
- __ Or(scratch1, scratch1, Operand(dst2));
- __ Branch(&done, eq, scratch1, Operand(zero_reg));
+ Label zero;
+ __ And(scratch1, dst_exponent, Operand(~HeapNumber::kSignMask));
+ __ Or(scratch1, scratch1, Operand(dst_mantissa));
+ __ Branch(&zero, eq, scratch1, Operand(zero_reg));
// Check that the value can be exactly represented by a 32-bit integer.
// Jump to not_int32 if that's not the case.
- DoubleIs32BitInteger(masm, dst1, dst2, scratch1, scratch2, not_int32);
+ Label restore_input_and_miss;
+ DoubleIs32BitInteger(masm, dst_exponent, dst_mantissa, scratch1, scratch2,
+ &restore_input_and_miss);
+
+ // dst_* were trashed. Reload the double value.
+ if (save_registers) {
+ __ Pop(dst_exponent, dst_mantissa);
+ }
+ __ lw(dst_exponent, FieldMemOperand(object, HeapNumber::kExponentOffset));
+ __ lw(dst_mantissa, FieldMemOperand(object, HeapNumber::kMantissaOffset));
+ __ Branch(&done);
- // dst1 and dst2 were trashed. Reload the double value.
- __ lw(dst2, FieldMemOperand(object, HeapNumber::kExponentOffset));
- __ lw(dst1, FieldMemOperand(object, HeapNumber::kMantissaOffset));
+ __ bind(&restore_input_and_miss);
+ if (save_registers) {
+ __ Pop(dst_exponent, dst_mantissa);
+ }
+ __ Branch(not_int32);
+
+ __ bind(&zero);
+ if (save_registers) {
+ __ Drop(2);
+ }
}
__ bind(&done);
@@ -979,14 +1004,14 @@ void FloatingPointHelper::LoadNumberAsInt32(MacroAssembler* masm,
void FloatingPointHelper::DoubleIs32BitInteger(MacroAssembler* masm,
- Register src1,
- Register src2,
+ Register src_exponent,
+ Register src_mantissa,
Register dst,
Register scratch,
Label* not_int32) {
// Get exponent alone in scratch.
__ Ext(scratch,
- src1,
+ src_exponent,
HeapNumber::kExponentShift,
HeapNumber::kExponentBits);
@@ -1006,11 +1031,11 @@ void FloatingPointHelper::DoubleIs32BitInteger(MacroAssembler* masm,
// Another way to put it is that if (exponent - signbit) > 30 then the
// number cannot be represented as an int32.
Register tmp = dst;
- __ srl(at, src1, 31);
+ __ srl(at, src_exponent, 31);
__ subu(tmp, scratch, at);
__ Branch(not_int32, gt, tmp, Operand(30));
// - Bits [21:0] in the mantissa are not null.
- __ And(tmp, src2, 0x3fffff);
+ __ And(tmp, src_mantissa, 0x3fffff);
__ Branch(not_int32, ne, tmp, Operand(zero_reg));
// Otherwise the exponent needs to be big enough to shift left all the
@@ -1021,20 +1046,20 @@ void FloatingPointHelper::DoubleIs32BitInteger(MacroAssembler* masm,
// Get the 32 higher bits of the mantissa in dst.
__ Ext(dst,
- src2,
+ src_mantissa,
HeapNumber::kMantissaBitsInTopWord,
32 - HeapNumber::kMantissaBitsInTopWord);
- __ sll(at, src1, HeapNumber::kNonMantissaBitsInTopWord);
+ __ sll(at, src_exponent, HeapNumber::kNonMantissaBitsInTopWord);
__ or_(dst, dst, at);
// Create the mask and test the lower bits (of the higher bits).
__ li(at, 32);
__ subu(scratch, at, scratch);
- __ li(src2, 1);
- __ sllv(src1, src2, scratch);
- __ Subu(src1, src1, Operand(1));
- __ And(src1, dst, src1);
- __ Branch(not_int32, ne, src1, Operand(zero_reg));
+ __ li(src_mantissa, 1);
+ __ sllv(src_exponent, src_mantissa, scratch);
+ __ Subu(src_exponent, src_exponent, Operand(1));
+ __ And(src_exponent, dst, src_exponent);
+ __ Branch(not_int32, ne, src_exponent, Operand(zero_reg));
}
« no previous file with comments | « no previous file | src/mips/stub-cache-mips.cc » ('j') | no next file with comments »

Powered by Google App Engine
This is Rietveld 408576698