[bazel] Capture output of updatemem to make it less verbose

updatemem likes to print a lot of things which makes the CI output
less readable for no particular benefit. This commit introduces a
bash script that runs updatmem and captures the output. If an error
occurs, it will print the path to the output and error logs. Those
files are also added to the output groups of the bitstream_splice
rules so that they can be queried if needed.

Signed-off-by: Amaury Pouly <[email protected]>

rules/opentitan/splice.bzl

@@ -37,6 +37,8 @@ def gen_vivado_mem_file(ctx, name, src, tool, swap_nibbles = True):
 
 def vivado_updatemem(ctx, name, src, instance, mmi, update, debug = False):
     spliced = ctx.actions.declare_file("{}.bit".format(name))
+    stdout = ctx.actions.declare_file("{}.out.log".format(name))
+    stderr = ctx.actions.declare_file("{}.err.log".format(name))
 
     # Vivado's `updatemem` only accepts bitstream filenames that end with `.bit`.
     # If the filename doesn't have that extension, symlink to a name that does.
@@ -57,17 +59,20 @@ def vivado_updatemem(ctx, name, src, instance, mmi, update, debug = False):
 
     ctx.actions.run(
         mnemonic = "SpliceBitstream",
-        outputs = [spliced],
+        outputs = [spliced, stdout, stderr],
         inputs = [src, mmi, update],
-        arguments = [args],
-        executable = "updatemem",
+        arguments = ["updatemem", args],
+        executable = ctx.executable._run_script,
         use_default_shell_env = False,
         execution_requirements = {
             "no-sandbox": "",
         },
-        env = ENV,
+        env = ENV | {
+            "RUN_CAPTURE_STDOUT": stdout.path,
+            "RUN_CAPTURE_STDERR": stderr.path,
+        },
     )
-    return spliced
+    return spliced, stdout, stderr
 
 def update_usr_access(ctx, name, src, tool):
     """Updates the USR_ACCESS value in the bistream.
@@ -125,7 +130,7 @@ def _bitstream_splice_impl(ctx):
             tool = tc.tools.gen_mem_image,
             swap_nibbles = ctx.attr.swap_nibbles,
         )
-        src = vivado_updatemem(
+        src, rom_updatemem_stdout, rom_updatemem_stderr = vivado_updatemem(
             ctx = ctx,
             name = "{}-rom".format(ctx.label.name),
             src = src,
@@ -148,7 +153,7 @@ def _bitstream_splice_impl(ctx):
             tool = tc.tools.gen_mem_image,
             swap_nibbles = ctx.attr.swap_nibbles,
         )
-        src = vivado_updatemem(
+        src, otp_updatemem_stdout, otp_updatemem_stderr = vivado_updatemem(
             ctx = ctx,
             name = "{}-otp".format(ctx.label.name),
             src = src,
@@ -164,7 +169,15 @@ def _bitstream_splice_impl(ctx):
         src = src,
         tool = tc.tools.opentitantool,
     )
-    return DefaultInfo(files = depset([output]))
+    return [
+        DefaultInfo(files = depset([output])),
+        OutputGroupInfo(
+            rom_updatemem_stdout = depset([rom_updatemem_stdout]),
+            rom_updatemem_stderr = depset([rom_updatemem_stderr]),
+            otp_updatemem_stdout = depset([otp_updatemem_stdout]),
+            otp_updatemem_stderr = depset([otp_updatemem_stderr]),
+        ),
+    ]
 
 bitstream_splice_ = rule(
     implementation = _bitstream_splice_impl,
@@ -177,6 +190,7 @@ bitstream_splice_ = rule(
         "swap_nibbles": attr.bool(default = True, doc = "Swap nybbles while preparing the memory image"),
         "debug": attr.bool(default = False, doc = "Emit debug info while updating"),
         "skip": attr.bool(default = False, doc = "Skip splice and do not modify the bitstream"),
+        "_run_script": attr.label(default = "//rules/scripts:run_and_capture", executable = True, cfg = "exec", doc = "Path to runner script that captures the output"),
     },
     toolchains = [LOCALTOOLS_TOOLCHAIN],
 )

rules/scripts/BUILD

@@ -38,3 +38,8 @@ sh_binary(
     name = "modid_check",
     srcs = ["modid_check.sh"],
 )
+
+sh_binary(
+    name = "run_and_capture",
+    srcs = ["run_and_capture.sh"],
+)

rules/scripts/run_and_capture.sh

@@ -0,0 +1,14 @@
+#!/usr/bin/env bash
+#
+# Copyright lowRISC contributors (OpenTitan project).
+# Licensed under the Apache License, Version 2.0, see LICENSE for details.
+# SPDX-License-Identifier: Apache-2.0
+#
+set -e
+
+# Run the program and redirect the stdout and stderr to given files
+if ! "$@" >$RUN_CAPTURE_STDOUT 2>$RUN_CAPTURE_STDERR; then
+    echo "$1 failed" >&2
+    echo "see stdout in $RUN_CAPTURE_STDOUT" >&2
+    echo "see stderr in $RUN_CAPTURE_STDERR" >&2
+fi