aboutsummaryrefslogtreecommitdiffstats
path: root/libevmasm/ConstantOptimiser.cpp
diff options
context:
space:
mode:
authorchriseth <c@ethdev.com>2017-03-03 23:17:21 +0800
committerchriseth <c@ethdev.com>2017-03-03 23:51:37 +0800
commitddc4918f3602744544b42da7507fc473e522b61c (patch)
treeaff58fac5cb7a9c51c5d7419e91f3e66400682b5 /libevmasm/ConstantOptimiser.cpp
parent05dac999223220fdb54c0d28781b3ef1d621061d (diff)
downloaddexon-solidity-ddc4918f3602744544b42da7507fc473e522b61c.tar.gz
dexon-solidity-ddc4918f3602744544b42da7507fc473e522b61c.tar.zst
dexon-solidity-ddc4918f3602744544b42da7507fc473e522b61c.zip
Add upper bound for computing constants.
Diffstat (limited to 'libevmasm/ConstantOptimiser.cpp')
-rw-r--r--libevmasm/ConstantOptimiser.cpp4
1 files changed, 3 insertions, 1 deletions
diff --git a/libevmasm/ConstantOptimiser.cpp b/libevmasm/ConstantOptimiser.cpp
index 86244e17..a1dfd21c 100644
--- a/libevmasm/ConstantOptimiser.cpp
+++ b/libevmasm/ConstantOptimiser.cpp
@@ -194,7 +194,7 @@ AssemblyItems ComputeMethod::findRepresentation(u256 const& _value)
// Is not always better, try literal and decomposition method.
AssemblyItems routine{u256(_value)};
bigint bestGas = gasNeeded(routine);
- for (unsigned bits = 255; bits > 8; --bits)
+ for (unsigned bits = 255; bits > 8 && m_maxSteps > 0; --bits)
{
unsigned gapDetector = unsigned(_value >> (bits - 8)) & 0x1ff;
if (gapDetector != 0xff && gapDetector != 0x100)
@@ -219,6 +219,8 @@ AssemblyItems ComputeMethod::findRepresentation(u256 const& _value)
else if (lowerPart < 0)
newRoutine.push_back(Instruction::SUB);
+ if (m_maxSteps > 0)
+ m_maxSteps--;
bigint newGas = gasNeeded(newRoutine);
if (newGas < bestGas)
{