Cleaned up first-block-in-function code.
Added cases for |PHEAP for PPARAM and PAUTO.
Made PPARAMOUT act more like PAUTO for purposes
of address generation and vardef placement.
Added cases for OCLOSUREVAR and Ops for getting closure
pointer.  Closure ops are scheduled at top of entry block
to capture DX.

Wrote test that seems to show proper behavior for addressed
parameters, locals, and returns.

Change-Id: Iee93ebf9e3d9f74cfb4d1c1da8038eb278d8a857
Reviewed-on: https://go-review.googlesource.com/14650Reviewed-by: Keith Randall <khr@golang.org>
Run-TryBot: David Chase <drchase@google.com>

Change-Id: I4deb03340e87f43179d5e22bf81843c17b5581fc
Reviewed-on: https://go-review.googlesource.com/14756Reviewed-by: David Chase <drchase@google.com>

There's no need for special ops for panicindex and panicslice.
Just use regular runtime calls.

Change-Id: I71b9b73f4f1ebce1220fdc1e7b7f65cfcf4b7bae
Reviewed-on: https://go-review.googlesource.com/14726Reviewed-by: David Chase <drchase@google.com>

Change-Id: I5de36244de4dcc4a9827ee0fa04526e3e3578e7f
Reviewed-on: https://go-review.googlesource.com/14755Reviewed-by: David Chase <drchase@google.com>

For variables which get SSA'd, SSA keeps track of all the def/kill.
It is only for on-stack variables that we need them.

This reduces stack frame sizes significantly because often the
only use of a variable was a varkill, and without that last use
the variable doesn't get allocated in the frame at all.

Fixes #12602

Change-Id: I3f00a768aa5ddd8d7772f375b25f846086a3e689
Reviewed-on: https://go-review.googlesource.com/14758Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>

We need to move any objects whose types are not SSA-able.

Fixes the "not lowered: Load ARRAY PTR64 mem" errors.

Change-Id: I7a0b609f917d7fb34bc9215fee4da15f9961cf6c
Reviewed-on: https://go-review.googlesource.com/14753Reviewed-by: David Chase <drchase@google.com>
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>

The frontend rewrites most literals, so we see only zero
ones during SSA construction.  We can implement those
using the existing zeroing behavior.

Change-Id: I390ad1be0a4b6729baf0c8936c7610aae2aef049
Reviewed-on: https://go-review.googlesource.com/14754Reviewed-by: David Chase <drchase@google.com>
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>

ptrvar -> ptrVar, etc.

Change-Id: Id38bed0e145711dfe3bdc9541ab4741da6a570a2
Reviewed-on: https://go-review.googlesource.com/14725Reviewed-by: Todd Neal <todd@tneal.org>

Taken over and completed from Josh's change
https://go-review.googlesource.com/#/c/14524/

Change-Id: If5d4f732843cc3e99bd5edda54458f0a8be73e91
Reviewed-on: https://go-review.googlesource.com/14690Reviewed-by: Josh Bleecher Snyder <josharian@gmail.com>

Generate AUNDEF for every exit block, not just for certain
control values.

Change-Id: Ife500ac5159ee790bc1e70c0e9b0b1f854bc4c47
Reviewed-on: https://go-review.googlesource.com/14721Reviewed-by: Josh Bleecher Snyder <josharian@gmail.com>

OCALLINTER, as well as ODEFER/OPROC with OCALLMETH/OCALLINTER.

Move all the call logic to its own routine, a lot of the
code is shared.

Change-Id: Ieac59596165e434cc6d1d7b5e46b78957e9c5ed3
Reviewed-on: https://go-review.googlesource.com/14464Reviewed-by: Todd Neal <todd@tneal.org>
Reviewed-by: David Chase <drchase@google.com>

A simpler way to do iface/slice comparisons.  Fixes some
cases of failed lowerings.

Change-Id: Ia252bc8648293a2d460f63c41f1591785543a1e9
Reviewed-on: https://go-review.googlesource.com/14493Reviewed-by: Josh Bleecher Snyder <josharian@gmail.com>

Change-Id: I1fbce8c421c48074a964b4d9481c92fbc3524f80
Reviewed-on: https://go-review.googlesource.com/14525Reviewed-by: Todd Neal <todd@tneal.org>

Fixes build.  Not great, but it will let others make progress.

Change-Id: If9cf2bbb5016e40aa91cf1c8bb62982ae2aed5e4
Reviewed-on: https://go-review.googlesource.com/14621Reviewed-by: Keith Randall <khr@golang.org>

Load-and-sign-extend opcodes were being generated in the
wrong block, leading to having more than one memory variable
live at once.  Fix the rules + add a test.

Change-Id: Iadf80e55ea901549c15c628ae295c2d0f1f64525
Reviewed-on: https://go-review.googlesource.com/14591Reviewed-by: Todd Neal <todd@tneal.org>
Run-TryBot: Todd Neal <todd@tneal.org>

For now, we only use typedmemmove.  This can be optimized
in future CLs.

Also add a feature to help with binary searching bad compilations.
Together with GOSSAPKG, GOSSAHASH specifies the last few binary digits
of the hash of function names that should be compiled.  So
GOSSAHASH=0110 means compile only those functions whose last 4 bits
of hash are 0110.  By adding digits to the front we can binary search
for the function whose SSA-generated code is causing a test to fail.

Change-Id: I5a8b6b70c6f034f59e5753965234cd42ea36d524
Reviewed-on: https://go-review.googlesource.com/14530Reviewed-by: Keith Randall <khr@golang.org>

Implement OSLICE, OSLICEARR, OSLICESTR, OSLICE3, OSLICE3ARR.

reviewer: Ignore the code in OINDEX, that's from CL 14466.

Change-Id: I00cc8aecd4c6f40ea5517cd660bb0ce759d91171
Reviewed-on: https://go-review.googlesource.com/14538Reviewed-by: Todd Neal <todd@tneal.org>

Change-Id: I984d3e0410ac38c4e42ae8e3670ea47e2140de76
Reviewed-on: https://go-review.googlesource.com/14466Reviewed-by: Alexandru Moșoi <alexandru@mosoi.ro>
Reviewed-by: Todd Neal <todd@tneal.org>

This makes deadstore elimination work reasonably again.

Change-Id: I3a8caced71f12dfb6c1d0c68b7a7d8d7a736ea23
Reviewed-on: https://go-review.googlesource.com/14536Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>

Change-Id: I5a683f532a5a0b2bc862d80c871e8dc6721016fc
Reviewed-on: https://go-review.googlesource.com/14534Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>

Change-Id: I1e5993e0e56481ce838c0e3979b1a3052e72dba5
Reviewed-on: https://go-review.googlesource.com/14535Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>

Change-Id: Iec61ca1bdc064c29ceca6d47f600d5643d0a64dd
Reviewed-on: https://go-review.googlesource.com/14533Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>

Move the AST to SSA conversion to the caller.
This enables it to be used in contexts in which
the RHS is already an *ssa.Value.

Change-Id: Ibb87210fb9fda095a9b7c7f4ad1264a7cbd269bf
Reviewed-on: https://go-review.googlesource.com/14521
Run-TryBot: Josh Bleecher Snyder <josharian@gmail.com>
Reviewed-by: Keith Randall <khr@golang.org>

Remove unnecessary local var split.

Change-Id: I907ef682b5fd9b3a67771edd1fe90c558f8937ea
Reviewed-on: https://go-review.googlesource.com/14523
Run-TryBot: Josh Bleecher Snyder <josharian@gmail.com>
Reviewed-by: Keith Randall <khr@golang.org>

Change-Id: I1f93ea65bbdc895cd4eff7545e1688a64d85aae5
Reviewed-on: https://go-review.googlesource.com/14520
Run-TryBot: Josh Bleecher Snyder <josharian@gmail.com>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>

Move to implicit (mostly) instead of explicit exit blocks.
RET and RETJMP have no outgoing edges - they implicitly exit.
CALL only has one outgoing edge, as its exception edge is
implicit as well.
Exit blocks are only used for unconditionally panicking code,
like the failed branches of nil and bounds checks.

There may now be more than one exit block.  No merges happen
at exit blocks.

The only downside is it is harder to find all the places code
can exit the method.  See the reverse dominator code for an
example.

Change-Id: I42e2fd809a4bf81301ab993e29ad9f203ce48eb0
Reviewed-on: https://go-review.googlesource.com/14462Reviewed-by: Josh Bleecher Snyder <josharian@gmail.com>

It was using 64-bit float comparison ops for complex64.
It should use 32-bit float comparison.

Fixes build.

Change-Id: I6452b227257fecc09e04cd092ccf328d1fc9917f
Reviewed-on: https://go-review.googlesource.com/14497
Run-TryBot: Keith Randall <khr@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>

Change-Id: Iefabce4eb0dbc313dd1863513b45307cc76c545a
Reviewed-on: https://go-review.googlesource.com/14468Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>

They were using the result type to look up the op, not the arg type.

Change-Id: I0641cba363fa6e7a66ad0860aa340106c10c2cea
Reviewed-on: https://go-review.googlesource.com/14469Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
Reviewed-by: Josh Bleecher Snyder <josharian@gmail.com>

Add line that was inadvertently removed.

Change-Id: I99ebc1041e984e408ae5825836c28b9891d6043b
Reviewed-on: https://go-review.googlesource.com/14470
Run-TryBot: Todd Neal <todd@tneal.org>
Reviewed-by: Keith Randall <khr@golang.org>

Change-Id: Ieb9cddf8876bf8cd5ee1705d9210d22c3959e8cc
Reviewed-on: https://go-review.googlesource.com/14329Reviewed-by: Keith Randall <khr@golang.org>
Run-TryBot: Todd Neal <todd@tneal.org>

This matches existing behavior, see issue #2196

Change-Id: Ifa9359b7c821115389f337a57de355c5ec23be8f
Reviewed-on: https://go-review.googlesource.com/14261Reviewed-by: Keith Randall <khr@golang.org>

Added tree numbering data structure.
Changed dominator query in CSE.
Removed skip-for-too-big patch in CSE.
Passes all.bash.

Change-Id: I98d7c61b6015c81f5edab553615db17bc7a58d68
Reviewed-on: https://go-review.googlesource.com/14326Reviewed-by: Keith Randall <khr@golang.org>

Change-Id: I352c7b9aab053959bc74c15861339e1dbe545ddc
Reviewed-on: https://go-review.googlesource.com/14404Reviewed-by: David Chase <drchase@google.com>

Evaluating args can overwrite arg area, so we can't write argsize and func
until args are evaluated.

Fixes test/recover.go, test/recover1.go, and test/fixedbugs/issue4066.go

Change-Id: I862e4934ccdb8661431bcc3e1e93817ea834ea3f
Reviewed-on: https://go-review.googlesource.com/14405Reviewed-by: David Chase <drchase@google.com>

Make sure that return blocks take a store as their control.  Without
this, code was getting inserted between the return and exit blocks.

Use AEND to mark the end of code.  The live variable analysis gets
confused when routines end like:
    JMP earlier
    RET
because the RET is unreachable.  The RET was incorrectly added to the
last basic block, rendering the JMP invisible to the CFG builder.

Change-Id: I91b32c8b37075347243ff039b4e4385856fba7cd
Reviewed-on: https://go-review.googlesource.com/14398Reviewed-by: Josh Bleecher Snyder <josharian@gmail.com>

Using the main package causes a binary to be generated.  That binary
clutters up git listings.

Use a non-main package instead, so the results of a successful
compilation are thrown away.

Change-Id: I3ac91fd69ad297a5c0fe035c22fdef290b7dfbc4
Reviewed-on: https://go-review.googlesource.com/14399Reviewed-by: Josh Bleecher Snyder <josharian@gmail.com>
Run-TryBot: Josh Bleecher Snyder <josharian@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>

Semi-regular merge of master into dev.ssa.

Change-Id: I48aa17700096a14f2a20ad07491ebfcd7529f6d5

Just a mechanical copy, no code changes.
This is to reduce code difference when adding the mips64 port.

Change-Id: Id06e975f414a7b09f4827167b30813b228a3bfaf
Reviewed-on: https://go-review.googlesource.com/14324Reviewed-by: Ian Lance Taylor <iant@golang.org>

Just a mechanical copy with filename renames, no code changes.
This is to reduce code difference when adding the mips64 port.

Change-Id: Id06e975f414a7b09f4827167b30813b228a3bfae
Reviewed-on: https://go-review.googlesource.com/14323Reviewed-by: Ian Lance Taylor <iant@golang.org>