Chromium Code Reviews
chromiumcodereview-hr@appspot.gserviceaccount.com (chromiumcodereview-hr) | Please choose your nickname with Settings | Help | Chromium Project | Gerrit Changes | Sign out
(17)

Unified Diff: src/arm/lithium-codegen-arm.cc

Issue 6833020: Revert revision 7582. (Closed) Base URL: http://v8.googlecode.com/svn/branches/bleeding_edge/
Patch Set: Created 9 years, 8 months 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 | « src/arm/code-stubs-arm.cc ('k') | src/arm/macro-assembler-arm.cc » ('j') | no next file with comments »
Expand Comments ('e') | Collapse Comments ('c') | Show Comments Hide Comments ('s')
Index: src/arm/lithium-codegen-arm.cc
===================================================================
--- src/arm/lithium-codegen-arm.cc (revision 7593)
+++ src/arm/lithium-codegen-arm.cc (working copy)
@@ -1069,130 +1069,40 @@
void LCodeGen::DoMulI(LMulI* instr) {
- LOperand* left_op = instr->InputAt(0);
- LOperand* right_op = instr->InputAt(1);
-
Register scratch = scratch0();
- Register left = ToRegister(left_op);
+ Register left = ToRegister(instr->InputAt(0));
+ Register right = EmitLoadRegister(instr->InputAt(1), scratch);
- ASSERT(left_op->Equals(instr->result()));
+ if (instr->hydrogen()->CheckFlag(HValue::kBailoutOnMinusZero) &&
+ !instr->InputAt(1)->IsConstantOperand()) {
+ __ orr(ToRegister(instr->TempAt(0)), left, right);
+ }
- bool can_overflow = instr->hydrogen()->CheckFlag(HValue::kCanOverflow);
- bool bailout_on_minus_zero =
- instr->hydrogen()->CheckFlag(HValue::kBailoutOnMinusZero);
-
- if (right_op->IsConstantOperand()) {
- // Use optimized code for specific constants.
- int32_t constant = ToInteger32(LConstantOperand::cast(right_op));
- Condition overflow_deopt_cond = kNoCondition;
-
- switch (constant) {
- case -1:
- overflow_deopt_cond = can_overflow ? vs : kNoCondition;
- __ rsb(left,
- left,
- Operand(0),
- can_overflow ? SetCC : LeaveCC);
- break;
- case 0:
- if (bailout_on_minus_zero) {
- // If left is strictly negative and the constant is null, the
- // result is -0. Deoptimize if required, otherwise return 0.
- __ cmp(left, Operand(0));
- DeoptimizeIf(mi, instr->environment());
- }
- __ mov(left, Operand(0));
- break;
- case 1:
- // Do nothing.
- break;
- default:
- // Multiplying by powers of two and powers of two plus or minus
- // one can be done faster with shifted operands.
- // For other constants we emit standard code.
- int32_t mask = constant >> 31;
- uint32_t constant_abs = (constant + mask) ^ mask;
-
- if (IsPowerOf2(constant_abs)) {
- if (!can_overflow) {
- int32_t shift = WhichPowerOf2(constant_abs);
- __ mov(left, Operand(left, LSL, shift));
- if (constant < 0) __ rsb(left, left, Operand(0));
- } else {
- // scratch:left = left * constant.
- __ mov(ip, Operand(constant));
- __ smull(left, scratch, left, ip);
- __ cmp(scratch, Operand(left, ASR, 31));
- overflow_deopt_cond = ne;
- }
- } else if (IsPowerOf2(constant_abs - 1)) {
- int32_t shift = WhichPowerOf2(constant_abs - 1);
- __ add(left,
- left,
- Operand(left, LSL, shift),
- can_overflow ? SetCC : LeaveCC);
- overflow_deopt_cond = can_overflow ? vs : kNoCondition;
- if (constant < 0) __ rsb(left, left, Operand(0));
- } else if (IsPowerOf2(constant_abs + 1)) {
- int32_t shift = WhichPowerOf2(constant_abs + 1);
- __ rsb(left,
- left,
- Operand(left, LSL, shift),
- can_overflow ? SetCC : LeaveCC);
- overflow_deopt_cond = can_overflow ? vs : kNoCondition;
- if (constant < 0) __ rsb(left, left, Operand(0));
- } else {
- if (!can_overflow) {
- __ mov(ip, Operand(constant));
- __ mul(left, left, ip);
- } else {
- // scratch:left = left * constant.
- __ mov(ip, Operand(constant));
- __ smull(left, scratch, left, ip);
- __ cmp(scratch, Operand(left, ASR, 31));
- overflow_deopt_cond = ne;
- }
- }
- break;
- }
-
-
- if (can_overflow && (constant != 0) && (constant != 1)) {
- ASSERT(overflow_deopt_cond != kNoCondition);
- DeoptimizeIf(overflow_deopt_cond, instr->environment());
- }
-
- if (bailout_on_minus_zero && (constant < 0)) {
- // The case of a null constant was handled separately.
- // If constant is negative and left is null, the result should be -0.
- __ cmp(left, Operand(0));
- DeoptimizeIf(eq, instr->environment());
- }
-
+ if (instr->hydrogen()->CheckFlag(HValue::kCanOverflow)) {
+ // scratch:left = left * right.
+ __ smull(left, scratch, left, right);
+ __ mov(ip, Operand(left, ASR, 31));
+ __ cmp(ip, Operand(scratch));
+ DeoptimizeIf(ne, instr->environment());
} else {
- Register right = EmitLoadRegister(right_op, scratch);
- if (bailout_on_minus_zero) {
- __ orr(ToRegister(instr->TempAt(0)), left, right);
- }
+ __ mul(left, left, right);
+ }
- if (can_overflow) {
- // scratch:left = left * right.
- __ smull(left, scratch, left, right);
- __ cmp(scratch, Operand(left, ASR, 31));
- DeoptimizeIf(ne, instr->environment());
+ if (instr->hydrogen()->CheckFlag(HValue::kBailoutOnMinusZero)) {
+ // Bail out if the result is supposed to be negative zero.
+ Label done;
+ __ cmp(left, Operand(0));
+ __ b(ne, &done);
+ if (instr->InputAt(1)->IsConstantOperand()) {
+ if (ToInteger32(LConstantOperand::cast(instr->InputAt(1))) <= 0) {
+ DeoptimizeIf(al, instr->environment());
+ }
} else {
- __ mul(left, left, right);
- }
-
- if (bailout_on_minus_zero) {
- // Bail out if the result is supposed to be negative zero.
- Label done;
- __ cmp(left, Operand(0));
- __ b(ne, &done);
+ // Test the non-zero operand for negative sign.
__ cmp(ToRegister(instr->TempAt(0)), Operand(0));
DeoptimizeIf(mi, instr->environment());
- __ bind(&done);
}
+ __ bind(&done);
}
}
« no previous file with comments | « src/arm/code-stubs-arm.cc ('k') | src/arm/macro-assembler-arm.cc » ('j') | no next file with comments »

Powered by Google App Engine
This is Rietveld 408576698