tree d9393d932ebba98cbc50518a3fcc0ed29bf6c313
parent 52393ad036e795f2da1e2692f17f76ccb00fb410
author Michael Hudson-Doyle <michael.hudson@canonical.com> 1447286157 +1300
committer Michael Hudson-Doyle <michael.hudson@canonical.com> 1447569739 +0000

cmd/go, runtime: always use position-independent code to invoke vsyscall helper on linux/386

golang.org/cl/16346 changed the runtime on linux/386 to invoke the vsyscall
helper via a PIC sequence (CALL 0x10(GS)) when dynamically linking. But it's
actually quite easy to make that code sequence work all the time, so do that,
and remove the ugly machinery that passed the buildmode from the go tool to the
assembly.

This means enlarging m.tls so that we can safely access 0x10(GS) (GS is set to
&m.tls + 4, so 0x10(GS) accesses m_tls[5]).

Change-Id: I1345c34029b149cb5f25320bf19a3cdd73a056fa
Reviewed-on: https://go-review.googlesource.com/16796
Reviewed-by: Ian Lance Taylor <iant@golang.org>