beam_validator: Strengthen validation of GC instructions OTP-14863
beam_validator did not verify that the Y registers were initialized
before executing the following instructions that could cause a GC:
bs_append/8
bs_init2/6
bs_init_bits/6
gc_bif1/5
gc_bif2/6
gc_bif3/7
test_heap/2
That means that, for example, an incorrect optimization that replaced
an 'allocate_zero' instruction with an 'allocate' instruction when it
was not safe, would not be rejected by beam_validtor, but would
instead cause a crash or other undefined behavior at runtime.
Also fix a minor bug in beam_type exposed by the stronger checking.
When compiling from .S files, beam_type did not handle the
init/1 instruction and could produce unsafe code.
The type optimizations for is_record and test_arity checked whether the arity was equal to the size stored in the type information, which is incorrect since said size is the *minimum* size of the tuple (as determined by previous instructions) and not its exact size. A future patch to the 'master' branch will restore these optimizations in a safe manner.
* lukas/compiler/add_to_dis/OTP-14784: compiler: Add +to_dis option that dumps loaded asm
* lukas/docs/xmllint_fixes/OTP-14721: ssl/ssh: Remove/ignore unused XML_FILES doc files Refactor xmllint check and make it fail on failure Add toplevel xmllint make target Conflicts: lib/crypto/doc/src/Makefile
* maint-18: Updated OTP version Prepare release ssh: Unicode encoding fix ssh: testcases for space trailing Hello msg Remove unused test include file from test suites eldap: Repair Makefile ssh: Don't remove trailing WS in Hello msg Conflicts: OTP_VERSION erts/doc/src/notes.xml erts/vsn.mk lib/compiler/doc/src/notes.xml lib/compiler/vsn.mk lib/crypto/test/blowfish_SUITE.erl lib/eldap/doc/src/notes.xml lib/eldap/vsn.mk lib/inets/test/httpd_load.erl lib/inets/test/httpd_mod.erl lib/inets/test/old_httpd_SUITE.erl lib/ssh/doc/src/notes.xml lib/ssh/vsn.mk lib/stdlib/test/zip_SUITE.erl otp_versions.table