X-Git-Url: https://www.ginac.de/ginac.git//ginac.git?p=ginac.git;a=blobdiff_plain;f=ginac%2Fmul.cpp;h=c7fb32a1527123a02b9fd82ffc677672af49c870;hp=81d648a599bd108319a225a959dea2accfca5899;hb=bb3808bb989db7e81755f1bfc7c6863d7c960e06;hpb=eb2c8f314d8cd32f8313837101881043594fd949

diff --git a/ginac/mul.cpp b/ginac/mul.cpp
index 81d648a5..c7fb32a1 100644
--- a/ginac/mul.cpp
+++ b/ginac/mul.cpp
@@ -693,9 +693,10 @@ ex mul::expand(unsigned options) const
 				exvector distrseq;
 				distrseq.reserve(n1*n2);
 				for (int i1=0; i1<n1; ++i1) {
-					for (int i2=0; i2<n2; ++i2) {
-						distrseq.push_back(add1.op(i1) * add2.op(i2));
-					}
+					// cache the first operand (for efficiency):
+					const ex op1 = add1.op(i1);
+					for (int i2=0; i2<n2; ++i2)
+						distrseq.push_back(op1 * add2.op(i2));
 				}
 				last_expanded = (new add(distrseq))->
 				                 setflag(status_flags::dynallocated | (options == 0 ? status_flags::expanded : 0));