aboutsummaryrefslogtreecommitdiffstats
path: root/lib/compiler/src/beam_block.erl
AgeCommit message (Collapse)Author
2011-12-09Update copyright yearsBjörn-Egil Dahlberg
2011-08-16compiler: Generate line instructionsBjörn Gustavsson
2010-10-12beam_block: Do optimizations in the safe orderBjörn Gustavsson
Moving of allocation instructions upwards in the instruction stream (in order to enable further optimizations) in beam_block, is implemented with the assumption that if a register {x,X} contains a valid term, then all other x register with lower numbers than X also contain valid terms. That assumption is true after code generation. The beam_utils:live_opt/1 optimization, however, may invalidate that assumption. For instance, if a receive statement exports a variable that is used, but the return value of the receive statement is not used, then {x,1} but not {x,0} contains a valid term at the end of the receive statement. If the receive statement is followed by {bif,self,{f,0},[],{x,0}}. {test_heap,NumberOfWords,2}. moving the allocation upwards will produce {test_heap,NumberOfWords,2}. {bif,self,{f,0},[],{x,0}}. which will cause the beam_validator pass to scream loudly that {x,0} is not live at the test_heap instruction. Fix the problem by doing the optimizations in reverse order. Reported-by: Jim Engquist
2010-05-20beam_block: Remove a clause that will never be executedBjörn Gustavsson
Since the introduction of literals in R12B, empty tuples are literals. Thus the put_tuple/2 instruction is always followed by at least one put/1 instruction. Therefore the alloc_may_pass/1 function in beam_block no longer needs a clause for for "put_tuple", because the clause for "put" will always be reached first (since the instruction stream is scanned in reverse execution order). Note that if the compiler would generate a "put_tuple 0 Dst" instruction for some unfathomable reason, we should still be because the run-time system will now refuse to load a module containing such an instruction.
2010-03-25Merge branch 'bg/compiler-remove-r11-support' into devErlang/OTP
* bg/compiler-remove-r11-support: compiler: Don't support the no_binaries option erts: Don't support the put_string/3 instruction compiler: Don't support the no_constant_pool option compiler: Don't support the r11 option test_server: Don't support communication with R11 nodes binary_SUITE: Don't test bit-level binary roundtrips with R11 nodes erts: Test compatibility of funs with R12 instead of R11 OTP-8531 bg/compiler-remove-r11-support
2010-03-22compiler: Don't support the no_constant_pool optionBjörn Gustavsson
The no_constant_pool option was implied by the r11 option. It turns off the usage of the constant (literal) pool, so that BEAM instructions that use constants can be loaded in an R11 system. Since the r11 option has been removed, there is no need to retain the no_constant_pool option.
2009-11-20The R13B03 release.OTP_R13B03Erlang/OTP