Re: Some questions about the gcc __sync intrinsics

Hi Yvan, On 9 March 2016 at 13:22, Yvan Roux wrote: > Hi Ed, > > On 9 March 2016 at 14:02, Edward Nevill wrote: >> Hi, >> >> >> Why the extra (unnecessary?) memory barrier? > > This is because Linaro gcc-5-branch is in sync with FSF gcc-5-branch > which contains a fix for this PR : > https://gcc

Re: Some questions about the gcc __sync intrinsics

> /usr/local/linare-gcc-5.2/bin/gcc -S -O3 -march=armv8-a+lse test.c > > add_int: > ldaddal w0, w0, [x1] > add w2, w0, w0 > mov w0, w2 > ret Am I going mad, or does this just return the contents of the memory location * 2. ldaddal w0, w0, [x1] Returns the

Re: Some questions about the gcc __sync intrinsics

On 10 March 2016 at 19:42, Edward Nevill wrote: >> /usr/local/linare-gcc-5.2/bin/gcc -S -O3 -march=armv8-a+lse test.c >> >> add_int: >> ldaddal w0, w0, [x1] >> add w2, w0, w0 >> mov w0, w2 >> ret > > Am I going mad, or does this just return the contents of t

Re: Some questions about the gcc __sync intrinsics

On 10 March 2016 at 19:52, Yvan Roux wrote: > On 10 March 2016 at 19:42, Edward Nevill wrote: >>> /usr/local/linare-gcc-5.2/bin/gcc -S -O3 -march=armv8-a+lse test.c >>> >>> add_int: >>> ldaddal w0, w0, [x1] >>> add w2, w0, w0 >>> mov w0, w2 >>> ret >> >> Am