nir: clamp-color-output support

Handled by tgsi_emulate for glsl->tgsi case.

Signed-off-by: Rob Clark <robclark@freedesktop.org>
Reviewed-by: Connor Abbott <cwabbott0@gmail.com>

freedreno: fix indentation

Signed-off-by: Rob Clark <robclark@freedesktop.org>

radeonsi: fix synchronization of shader images

This fixes the winsys->cs_is_buffer_referenced query, which is used for
synchronization before buffers are mapped.

Reviewed-by: Nicolai Hähnle <nicolai.haehnle@amd.com>

st/glsl_to_tgsi: fix potential crash when allocating temporaries

When index - t->temps_size is greater than 4096, allocating space for
temporaries on demand will miserably crash. This can happen when a game
uses a lot of temporaries like the recent released Tomb raider.

Signed-off-by: Samuel Pitoiset <samuel.pitoiset@gmail.com>
Reviewed-by: Ilia Mirkin <imirkin@alum.mit.edu>
Reviewed-by: Nicolai Hähnle <nicolai.haehnle@amd.com>
Cc: "11.1 11.2" <mesa-stable@lists.freedesktop.org>

glsl: Lower vector_extracts to swizzles after lower_vector_derefs.

lower_vector_derefs can produce new vector_extract operations.
Neither i965 nor st_glsl_to_tgsi can handle them, so we'd best
convert them to swizzles.

Together with the previous patch, this fixes assertion failures in
GLideN64, as well as a new Piglit test which reproduces the issue:
spec/glsl-1.10/compiler/vector-dereference-in-dereference.frag

Cc: mesa-stable@lists.freedesktop.org
Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=95164
Signed-off-by: Kenneth Graunke <kenneth@whitecape.org>
Reviewed-by: Ian Romanick <ian.d.romanick@intel.com>

glsl: Convert lower_vec_index_to_swizzle to a rvalue visitor.

The old visitor missed some cases.  For example, it wouldn't handle
an ir_dereference_array with a vector_extract as the index.

Rather than trying to add the missing cases, just rewrite it as an
ir_rvalue_visitor.  This makes it easy to replace any expression,
and is much less code.

Cc: mesa-stable@lists.freedesktop.org
Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=95164
Signed-off-by: Kenneth Graunke <kenneth@whitecape.org>
Reviewed-by: Ian Romanick <ian.d.romanick@intel.com>

mesa: simplify _mesa_Lightfv

Signed-off-by: Thomas Faller <tfaller1@gmx.de>
Reviewed-by: Brian Paul <brianp@vmware.com>

gallium/radeon: fix crash in r600_set_streamout_targets

Protect against dereferencing a gap in the targets array. This was triggered
by a test in the Khronos CTS.

Cc: "11.1 11.2" <mesa-stable@lists.freedesktop.org>
Reviewed-by: Marek Olšák <marek.olsak@amd.com>

st/glsl_to_tgsi: reduce stack explosion in recursive expression visitor

In optimized builds, visit(ir_expression *) experiences inlining with gcc that
leads the function to have a roughly 32KB stack frame. This is a problem given
that the function is called recursively. In non-optimized builds, the stack
frame is much smaller, hence one gets crashes that happen only in optimized
builds.

Arguably there is a compiler bug or at least severe misfeature here. In any
case, the easy thing to do for now seems to be moving the bulk of the
non-recursive code into a separate function. This is sufficient to convince my
version of gcc not to blow up the stack frame of the recursive part. Just to be
sure, add the gcc-specific noinline attribute to prevent this bug from
reoccuring if inliner heuristics change.

v2: put ATTRIBUTE_NOINLINE into macros.h

Cc: "11.1 11.2" <mesa-stable@lists.freedesktop.org>
Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=95133
Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=95026
Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=92850
Reviewed-by: Ilia Mirkin <imirkin@alum.mit.edu>
Reviewed-by: Rob Clark <robdclark@gmail.com>

tgsi/text: fix parsing of memory instructions

Properly handle Target and Format parameters when present.

Reviewed-by: Ilia Mirkin <imirkin@alum.mit.edu>
Reviewed-by: Dave Airlie <airlied@redhat.com>

tgsi/text: add str_match_name_from_array

Reviewed-by: Ilia Mirkin <imirkin@alum.mit.edu>
Reviewed-by: Dave Airlie <airlied@redhat.com>

tgsi/text: add str_match_format helper function

Reviewed-by: Ilia Mirkin <imirkin@alum.mit.edu>
Reviewed-by: Dave Airlie <airlied@redhat.com>

tgsi/build: pass Memory.Texture and .Format through tgsi_build_full_instruction

Reviewed-by: Ilia Mirkin <imirkin@alum.mit.edu>
Reviewed-by: Dave Airlie <airlied@redhat.com>

tgsi/dump: signal nospace when the last print exceeded the size

Previously, there was a bug where nospace wasn't signalled if it just so
happened that the very last print exceeded the available space.

Reviewed-by: Dave Airlie <airlied@redhat.com>

tgsi/dump: shared dump_ctx initialization

Reviewed-by: Dave Airlie <airlied@redhat.com>

st/omx: don't return early in vid_enc_EncodeFrame()

Earlier commit plugged a memory leak, although it missed a pair of
brackets. Thus we unconditionally returned even in the case of no error.

Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=95203
Fixes: b87856d25d1 ("st/omx: Fix resource leak on OMX_ErrorNone")
Tested-by: Andy Furniss <adf.lists@gmail.com>
Acked-by: Robert Foss <robert.foss@collabora.com>
Signed-off-by: Emil Velikov <emil.velikov@collabora.com>
---
What an embarassing bug - missing brackets. Andy can you confirm that it
resolves the issue ?

glsl: Checks for interpolation into its own function.

This generalizes the validation also to be done for variables inside
interface blocks, which, for some cases, was missing.

For a discussion about the additional validation cases included see
https://lists.freedesktop.org/archives/mesa-dev/2016-March/109117.html
and Khronos bug #15671.

Reviewed-by: Samuel Iglesias Gonsálvez <siglesias@igalia.com>
Signed-off-by: Andres Gomez <agomez@igalia.com>

nir/algebraic: Support lowering for both 64 and 32-bit ldexp

Reviewed-by: Samuel Iglesias Gonsálvez <siglesias@igalia.com>

nir/opcodes: Make ldexp take an explicitly 32-bit int

There is no sense in having the double version of ldexp take a 64-bit
integer.  Instead, let's just take a 32-bit int all the time.  This also
matches what GLSL does where both variants of ldexp take a regular integer
for the exponent argument.

Reviewed-by: Samuel Iglesias Gonsálvez <siglesias@igalia.com>

nir/opcodes: Simplify the expressions for [un]pack_double

The new expressions are more explicit in terms of where the bits go so it's
a little easier to tell what's going on.  This is the way GLSL specifies
things so it's a bit easier to verify too.  It also has the benifit that
the new expressions easily vectorize so we can constant-fold vector forms
of the _split versions correctly.

Reviewed-by: Samuel Iglesias Gonsálvez <siglesias@igalia.com>

mesa: Fix indirect draw buffer size check on 32-bit systems.

Fixes dEQP-GLES31.functional subtests:
draw_indirect.negative.command_offset_not_in_buffer_signed32_wrap
draw_indirect.negative.command_offset_not_in_buffer_unsigned32_wrap

These tests use really large values that overflow GLsizeiptr, at
which point the buffer size isn't less than "end".

Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=95138
Signed-off-by: Kenneth Graunke <kenneth@whitecape.org>
Reviewed-by: Alejandro Piñeiro <apinheiro@igalia.com>
Reviewed-by: Mark Janes <mark.a.janes@intel.com>

nir: Switch the arguments to nir_foreach_def

This matches the "foreach x in container" pattern found in many other
programming languages.  Generated by the following regular expression:

s/nir_foreach_def(\([^,]*\),\s*\([^,]*\))/nir_foreach_def(\2, \1)/

Reviewed-by: Eduardo Lima Mitev <elima@igalia.com>
Reviewed-by: Ian Romanick <ian.d.romanick@intel.com>

nir: Switch the arguments to nir_foreach_use and friends

This matches the "foreach x in container" pattern found in many other
programming languages.  Generated by the following regular expression:

s/nir_foreach_use(\([^,]*\),\s*\([^,]*\))/nir_foreach_use(\2, \1)/

and similar expressions for nir_foreach_use_safe, etc.

Reviewed-by: Ian Romanick <ian.d.romanick@intel.com>

nir: Switch the arguments to nir_foreach_function

This matches the "foreach x in container" pattern found in many other
programming languages.  Generated by the following regular expression:

s/nir_foreach_function(\([^,]*\),\s*\([^,]*\))/nir_foreach_function(\2, \1)/

Reviewed-by: Ian Romanick <ian.d.romanick@intel.com>

nir: Switch the arguments to nir_foreach_parallel_copy_entry

This matches the "foreach x in container" pattern found in many other
programming languages.

Reviewed-by: Eduardo Lima Mitev <elima@igalia.com>
Reviewed-by: Ian Romanick <ian.d.romanick@intel.com>

nir: Switch the arguments to nir_foreach_phi_src

This matches the "foreach x in container" pattern found in many other
programming languages.  Generated by the following regular expression:

s/nir_foreach_phi_src(\([^,]*\),\s*\([^,]*\))/nir_foreach_phi_src(\2, \1)/

and a similar expression for nir_foreach_phi_src_safe.

Reviewed-by: Eduardo Lima Mitev <elima@igalia.com>

nir: Switch the arguments to nir_foreach_instr

This matches the "foreach x in container" pattern found in many other
programming languages.  Generated by the following regular expression:

s/nir_foreach_instr(\([^,]*\),\s*\([^,]*\))/nir_foreach_instr(\2, \1)/

and similar expressions for nir_foreach_instr_safe etc.

Reviewed-by: Ian Romanick <ian.d.romanick@intel.com>

anv/lower_push_constants: fixup for nir_foreach_block()

Signed-off-by: Jason Ekstrand <jason@jlekstrand.net>

anv/apply_pipeline_layout: fixup for nir_foreach_block()

Signed-off-by: Jason Ekstrand <jason@jlekstrand.net>

anv/apply_dynamic_offsets: fixup for nir_foreach_block()

Signed-off-by: Jason Ekstrand <jason@jlekstrand.net>

i965/nir: fixup for new foreach_block()

Reviewed-by: Jason Ekstrand <jason@jlekstrand.net>

nir/algebraic: fixup for new foreach_block()

Reviewed-by: Jason Ekstrand <jason@jlekstrand.net>

nir/validate: fixup for new foreach_block()

Reviewed-by: Jason Ekstrand <jason@jlekstrand.net>

nir/nir_worklist: fixup for new foreach_block()

Reviewed-by: Jason Ekstrand <jason@jlekstrand.net>

nir/remove_dead_variables: fixup for new foreach_block()

Reviewed-by: Jason Ekstrand <jason@jlekstrand.net>

nir/split_var_copies: fixup for new foreach_block()

Reviewed-by: Jason Ekstrand <jason@jlekstrand.net>

nir/repair_ssa: fixup for new foreach_block()

Reviewed-by: Jason Ekstrand <jason@jlekstrand.net>

nir/opt_peephole_select: fixup for new foreach_block()

Reviewed-by: Jason Ekstrand <jason@jlekstrand.net>

nir/phi_builder: fixup for new foreach_block()

Reviewed-by: Jason Ekstrand <jason@jlekstrand.net>

nir/opt_cp: fixup for new foreach_block()

Reviewed-by: Jason Ekstrand <jason@jlekstrand.net>

nir/opt_remove_phis: fixup for new foreach_block()

Reviewed-by: Jason Ekstrand <jason@jlekstrand.net>

nir/opt_undef: fixup for new foreach_block()

Reviewed-by: Jason Ekstrand <jason@jlekstrand.net>

nir/opt_dead_cf: fixup for new foreach_block()

Reviewed-by: Jason Ekstrand <jason@jlekstrand.net>

nir/opt_dce: fixup for new foreach_block()

Reviewed-by: Jason Ekstrand <jason@jlekstrand.net>

nir/opt_gcm: fixup for new foreach_block()

Reviewed-by: Jason Ekstrand <jason@jlekstrand.net>

nir/opt_constant_folding: fixup for new foreach_block()

Reviewed-by: Jason Ekstrand <jason@jlekstrand.net>

nir/lower_samplers: fixup for new foreach_block()

Reviewed-by: Jason Ekstrand <jason@jlekstrand.net>

nir/normalize_cubemap_coords: fixup for new foreach_block()

Reviewed-by: Jason Ekstrand <jason@jlekstrand.net>

nir/lower_var_copies: fixup for new foreach_block()

Reviewed-by: Jason Ekstrand <jason@jlekstrand.net>

nir/move_vec_src_uses_to_dest: fixup for new foreach_block()

Reviewed-by: Jason Ekstrand <jason@jlekstrand.net>

nir/lower_vars_to_ssa: fixup for new foreach_block()

Reviewed-by: Jason Ekstrand <jason@jlekstrand.net>

nir/lower_vec_to_movs: fixup for new foreach_block()

Reviewed-by: Jason Ekstrand <jason@jlekstrand.net>

nir/lower_idiv: fixup for new foreach_block()

Reviewed-by: Jason Ekstrand <jason@jlekstrand.net>

nir/lower_to_source_mods: fixup for new foreeach_block()

Reviewed-by: Jason Ekstrand <jason@jlekstrand.net>

nir/lower_io: fixup for new foreach_block()

Reviewed-by: Jason Ekstrand <jason@jlekstrand.net>

nir/lower_system_values: fixup for new foreach_block()

Reviewed-by: Jason Ekstrand <jason@jlekstrand.net>

nir/lower_phis_to_scalar: fixup for new foreach_block()

Reviewed-by: Jason Ekstrand <jason@jlekstrand.net>

nir/lower_indirect_derefs: fixup for new foreach_block()

v2 (Jason Ekstrand): Use nir_foreach_block_safe

Reviewed-by: Jason Ekstrand <jason@jlekstrand.net>

nir/nir_lower_global_vars: fixup for new foreach_block()

Reviewed-by: Jason Ekstrand <jason@jlekstrand.net>

nir/lower_atomics: fixup for new foreach_block()

Reviewed-by: Jason Ekstrand <jason@jlekstrand.net>

nir/lower_load_const: fixup for new foreach_block()

Reviewed-by: Jason Ekstrand <jason@jlekstrand.net>

nir/lower_locals_to_regs: fixup for new foreach_block()

Reviewed-by: Jason Ekstrand <jason@jlekstrand.net>

nir/lower_gs_intrinsics: fixup for new foreach_block()

v2 (Jason Ekstrand): Use nir_foreach_block_safe

Reviewed-by: Jason Ekstrand <jason@jlekstrand.net>

nir/nir: fixup for new foreach_block()

Reviewed-by: Jason Ekstrand <jason@jlekstrand.net>

nir/lower_clip: fixup for new foreach_block()

Reviewed-by: Jason Ekstrand <jason@jlekstrand.net>

nir/lower_alu_to_scalar: fixup for new foreach_block()

Reviewed-by: Jason Ekstrand <jason@jlekstrand.net>

nir/liveness: fixup for new foreach_block()

Reviewed-by: Jason Ekstrand <jason@jlekstrand.net>

nir/inline_functions: fixup for new foreach_block()

Reviewed-by: Jason Ekstrand <jason@jlekstrand.net>

nir/from_ssa: fixup for new foreach_block()

Reviewed-by: Jason Ekstrand <jason@jlekstrand.net>

nir/dominance: fixup for new foreach_block()

Reviewed-by: Jason Ekstrand <jason@jlekstrand.net>

nvc0: stick compute kernel arguments into uniform_bo

Having one buffer object for input kernel arguments coming from clover
and an other one for OpenGL user uniforms is unnecessary. Using the
uniform_bo object for both GL/CL uniforms avoids to declare a new BO.

This only affects compute programs but it should not hurt anything
because the states are dirtied and data will get reuploaded.

Signed-off-by: Samuel Pitoiset <samuel.pitoiset@gmail.com>
Reviewed-by: Hans de Goede <hdegoede@redhat.com>
Reviewed-by: Ilia Mirkin <imirkin@alum.mit.edu>

swr: remove duplicated constant update code

Reviewed-by: Bruce Cherniak <bruce.cherniak@intel.com>

gallium/radeon: add the size only once in r600_context_add_resource_size

Reviewed-by: Alex Deucher <alexander.deucher@amd.com>

winsys/radeon: enlarge buffer_indices_hashlist

Enlarge the buffer hashlist to prevent large numbers of misses
due to adding more buffers than can be cached in the hashlist.

Ported from winsys/amdgpu: 6373845d985d65c00f7c62b793e67ae5106eabff

Reviewed-by: Alex Deucher <alexander.deucher@amd.com>

gallium/radeon: drop support for LINEAR_GENERAL layout

Unused. All texture imports use LINEAR_ALIGNED regardless of what
the DDX does.

Reviewed-by: Alex Deucher <alexander.deucher@amd.com>

radeonsi: rework clear_buffer flags

Changes:
- don't flush DB for fast color clears
- don't flush any caches for initial clears
- remove the flag from si_copy_buffer, always assume shader coherency

Reviewed-by: Nicolai Hähnle <nicolai.haehnle@amd.com>

anv/dynamic_offsets: Fix the order of arguments to nir_build_imm

anv: Fix a build error caused by recent fp64 NIR changes

nir: Try to warn when C99 extensions are used in nir headers.

Ideally we'd have nir.h being included with -Wpedantic too, but it fails
with:

src/compiler/nir/nir.h:754:20: warning: ISO C++ forbids zero-size array ‘src’ [-Wpedantic]
    nir_alu_src src[];
                    ^
In file included from src/compiler/nir/glsl_to_nir.cpp:42:0:
src/compiler/nir/nir.h:919:16: warning: ISO C++ forbids zero-size array ‘src’ [-Wpedantic]
    nir_src src[];

Reviewed-by: Connor Abbott <cwabbott0@gmail.com>

nir: Remove spurious ; after nir_builder functions.

Makes -pedantic happy.

Reviewed-by: Connor Abbott <cwabbott0@gmail.com>

nir: Remove spurious ; after namespace.

Makes -pedantic happy.

Reviewed-by: Connor Abbott <cwabbott0@gmail.com>

nir: Avoid C99 field initializers.

As they are not standard C++ and are not supported by MSVC C++ compiler.

Just have nir_imm_double match nir_imm_float above.

Reviewed-by: Connor Abbott <cwabbott0@gmail.com>
Reviewed-by: Sinclair Yeh <syeh@vmware.com>

gallium/util: s/Elements/ARRAY_SIZE/

Reviewed-by: Nicolai Hähnle <nicolai.haehnle@amd.com>

mesa: improve comment on _mesa_check_disallowed_mapping(), return bool

The old comment was a bit terse.  Also, change the function return
type to bool.

Reviewed-by: Marek Olšák <marek.olsak@amd.com>
Reviewed-by: Ian Romanick <ian.d.romanick@intel.com>

radeonsi: remove needless cache flushes at the end of CP DMA operations

not needed AFAIK

Reviewed-by: Nicolai Hähnle <nicolai.haehnle@amd.com>

radeonsi: remove flushes at the beginning and end of IBs done by the kernel

Reviewed-by: Nicolai Hähnle <nicolai.haehnle@amd.com>

nir: Add lrp lowering for doubles in opt_algebraic

Some hardware (i965 on Broadwell generation, for example) does not support
natively the execution of lrp instruction with double arguments.

Add 'lower_flrp64' flag to lower this instruction in that case.

v2:
   - Rename lower_flrp_double to lower_flrp64 (Jason)
   - Fix typo (Jason)
   - Adapt the code to define bit_size information in the opcodes.

Signed-off-by: Samuel Iglesias Gonsálvez <siglesias@igalia.com>
Reviewed-by: Jason Ekstrand <jason@jlekstrand.net>

nir: rename lower_flrp to lower_flrp32

A later patch will add lower_flrp64 option to NIR.

Signed-off-by: Samuel Iglesias Gonsálvez <siglesias@igalia.com>
Reviewed-by: Jason Ekstrand <jason@jlekstrand.net>

nir/lower_double_ops: lower round_even()

At least i965 hardware does not have native support for round_even() on doubles.

Reviewed-by: Matt Turner <mattst88@gmail.com>

nir/lower_double_ops: lower fract()

At least i965 hardware does not have native support for fract() on doubles.

Reviewed-by: Jason Ekstrand <jason@jlekstrand.net>

nir/lower_double_ops: lower ceil()

At least i965 hardware does not have native support for ceil on doubles.

v2 (Sam):
   - Improve the lowering pass to remove one bcsel (Jason).

Signed-off-by: Samuel Iglesias Gonsálvez <siglesias@igalia.com>
Reviewed-by: Jason Ekstrand <jason@jlekstrand.net>

nir/lower_double_ops: lower floor()

At least i965 hardware does not have native support for floor on doubles.

v2 (Sam):
  - Improve the lowering pass to remove one bcsel (Jason)

Signed-off-by: Samuel Iglesias Gonsálvez <siglesias@igalia.com>
Reviewed-by: Jason Ekstrand <jason@jlekstrand.net>

nir/lower_double_ops: lower trunc()

At least i965 hardware does not have native support for truncating doubles.

v2:
  - Simplified the implementation significantly.
  - Fixed the else branch, that was not doing what we wanted.

Reviewed-by: Jason Ekstrand <jason@jlekstrand.net>

nir: add a pass to lower some double operations

v2: Move to compiler/nir (Iago)
v3: Use nir_imm_int() to load the constants (Sam)
v4 (Sam):
  - Undo line-wrap (Jason).
  - Fix comment (Jason).
  - Improve generated code for get_signed_inf() function (Connor).

Signed-off-by: Samuel Iglesias Gonsálvez <siglesias@igalia.com>
Reviewed-by: Jason Ekstrand <jason@jlekstrand.net>

nir/builder: add nir_imm_double()

Reviewed-by: Jason Ekstrand <jason@jlekstrand.net>

nir/builder: Add bit_size info to nir_build_imm()

v2:
- Group num_components and bit_size together (Jason)

Signed-off-by: Samuel Iglesias Gonsálvez <siglesias@igalia.com>
Reviewed-by: Jason Ekstrand <jason@jlekstrand.net>

radeonsi: check if value is negative

Fixes a Coverity defect by adding checks to see if a value is negative
before using it to index an array. By checking the value first it makes
the code a bit safer but overall should not have a big impact.

CID: 1355598

Signed-off-by: Jakob Sinclair <sinclair.jakob@openmailbox.org>
Signed-off-by: Marek Olšák <marek.olsak@amd.com>

clover: Fix build against clang SVN >= r267772

(Re-pushing previous fix for clang SVN r265359, which was reverted in
the meantime)

Signed-off-by: Michel Dänzer <michel.daenzer@amd.com>
Reviewed-by: Tom Stellard <thomas.stellard@amd.com>

glsl: fix lowering outputs for early/nested returns

Return statements in conditional blocks were not having their
output varyings lowered correctly.

This patch fixes the following piglit tests:
/spec/glsl-1.10/execution/vs-float-main-return
/spec/glsl-1.10/execution/vs-vec2-main-return
/spec/glsl-1.10/execution/vs-vec3-main-return

Signed-off-by: Lars Hamre <chemecse@gmail.com>
Reviewed-by: Timothy Arceri <timothy.arceri@collabora.com>

nir: rewrite nir_foreach_block and friends

Previously, these were functions which took a callback. This meant that
the per-block code had to be in a separate function, and all the data
that you wanted to pass in had to be a single void *. They walked the
control flow tree recursively, doing a depth-first search, and called
the callback in a preorder, matching the order of the original source
code. But since each node in the control flow tree has a pointer to its
parent, we can implement a "get-next" and "get-previous" method that
does the same thing that the recursive function did with no state at
all. This lets us rewrite nir_foreach_block() as a simple for loop,
which lets us greatly simplify its users in some cases. This does
require us to rewrite every user, although the transformation from the
old nir_foreach_block() to the new nir_foreach_block() is mostly
trivial.

One subtlety, though, is that the new nir_foreach_block() won't handle
the case where the current block is deleted, which the old one could.
There's a new nir_foreach_block_safe() which implements the standard
trick for solving this. Most users don't modify control flow, though, so
they won't need it. Right now, only opt_select_peephole needs it.

The old functions are reimplemented in terms of the new macros, although
they'll go away after everything is converted.

v2: keep an implementation of the old functions around
v3 (Jason Ekstrand): A small cosmetic change and a bugfix in the loop
   handling of nir_cf_node_cf_tree_last().
v4 (Jason Ekstrand): Use the _safe macro in foreach_block_reverse_call

Reviewed-by: Jason Ekstrand <jason@jlekstrand.net>