Revision: 4929
Author: [email protected]
Date: Wed Jun 23 06:44:11 2010
Log: ARM: Fix bug introduced in 4783 (2.2.15) that caused the
result of 1 << x to be miscalculated for some inputs.
Review URL: http://codereview.chromium.org/2848021
http://code.google.com/p/v8/source/detail?r=4929
Modified:
/branches/bleeding_edge/src/arm/codegen-arm.cc
/branches/bleeding_edge/test/mjsunit/smi-ops.js
=======================================
--- /branches/bleeding_edge/src/arm/codegen-arm.cc Mon Jun 21 03:34:25 2010
+++ /branches/bleeding_edge/src/arm/codegen-arm.cc Wed Jun 23 06:44:11 2010
@@ -969,45 +969,20 @@
case Token::MOD:
case Token::BIT_OR:
case Token::BIT_XOR:
- case Token::BIT_AND: {
- if (reversed_) {
- if (tos_register_.is(r0)) {
- __ mov(r1, Operand(Smi::FromInt(value_)));
- } else {
- ASSERT(tos_register_.is(r1));
- __ mov(r0, Operand(Smi::FromInt(value_)));
- lhs = r0;
- rhs = r1;
- }
- } else {
- if (tos_register_.is(r1)) {
- __ mov(r0, Operand(Smi::FromInt(value_)));
- } else {
- ASSERT(tos_register_.is(r0));
- __ mov(r1, Operand(Smi::FromInt(value_)));
- lhs = r0;
- rhs = r1;
- }
- }
- break;
- }
-
+ case Token::BIT_AND:
case Token::SHL:
case Token::SHR:
case Token::SAR: {
- if (!reversed_) {
- if (tos_register_.is(r1)) {
- __ mov(r0, Operand(Smi::FromInt(value_)));
- } else {
- ASSERT(tos_register_.is(r0));
- __ mov(r1, Operand(Smi::FromInt(value_)));
- lhs = r0;
- rhs = r1;
- }
+ if (tos_register_.is(r1)) {
+ __ mov(r0, Operand(Smi::FromInt(value_)));
} else {
- ASSERT(op_ == Token::SHL);
+ ASSERT(tos_register_.is(r0));
__ mov(r1, Operand(Smi::FromInt(value_)));
}
+ if (reversed_ == tos_register_.is(r1)) {
+ lhs = r0;
+ rhs = r1;
+ }
break;
}
=======================================
--- /branches/bleeding_edge/test/mjsunit/smi-ops.js Thu May 6 01:15:15 2010
+++ /branches/bleeding_edge/test/mjsunit/smi-ops.js Wed Jun 23 06:44:11 2010
@@ -685,3 +685,8 @@
assertEquals(24, LeftShiftThreeBy(35));
assertEquals(24, LeftShiftThreeBy(67));
assertEquals(24, LeftShiftThreeBy(-29));
+
+// Regression test for a bug in the ARM code generator. For some register
+// allocations we got the Smi overflow case wrong.
+function f(x, y) { return y + ( 1 << (x & 31)); }
+assertEquals(-2147483647, f(31, 1));
--
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