From 407ba59042edf779bc50dfe886f20af8917508a3 Mon Sep 17 00:00:00 2001
From: Zachary Snow <zach@zachjs.com>
Date: Sun, 5 Sep 2021 19:54:36 -0400
Subject: [PATCH] add internal --dump-prefix utility

---
 README.md      |  2 ++
 src/Convert.hs | 47 ++++++++++++++++++++++++++++++++++++++---------
 src/Job.hs     |  4 ++++
 src/sv2v.hs    |  6 +++---
 4 files changed, 47 insertions(+), 12 deletions(-)

diff --git a/README.md b/README.md
index 88038bd..826b2af 100644
--- a/README.md
+++ b/README.md
@@ -103,6 +103,8 @@ Conversion:
 Other:
      --oversized-numbers    Disable standard-imposed 32-bit limit on unsized
                             number literals (e.g., 'h1_ffff_ffff, 4294967296)
+     --dump-prefix=PATH     Create intermediate output files with the given
+                            path prefix; used for internal debugging
      --help                 Display help message
      --version              Print version information
      --numeric-version      Print just the version number
diff --git a/src/Convert.hs b/src/Convert.hs
index 73ad9ac..62e236e 100644
--- a/src/Convert.hs
+++ b/src/Convert.hs
@@ -6,6 +6,8 @@
 
 module Convert (convert) where
 
+import Control.Monad ((>=>))
+
 import Language.SystemVerilog.AST
 import qualified Job (Exclude(..))
 
@@ -53,6 +55,7 @@ import qualified Convert.Unsigned
 import qualified Convert.Wildcard
 
 type Phase = [AST] -> [AST]
+type IOPhase = [AST] -> IO [AST]
 type Selector = Job.Exclude -> Phase -> Phase
 
 finalPhases :: Selector -> [Phase]
@@ -109,22 +112,48 @@ initialPhases selectExclude =
     , Convert.UnnamedGenBlock.convert
     ]
 
-convert :: [Job.Exclude] -> Phase
-convert excludes =
-    final . loopMain . initial
+convert :: FilePath -> [Job.Exclude] -> IOPhase
+convert dumpPrefix excludes =
+    step "parse"   id      >=>
+    step "initial" initial >=>
+    loop 1 "main"  main    >=>
+    step "final"   final
     where
         final = combine $ finalPhases selectExclude
         main = combine $ mainPhases selectExclude
         initial = combine $ initialPhases selectExclude
         combine = foldr1 (.)
-        loopMain :: Phase
-        loopMain descriptions =
-            if descriptions == descriptions'
-                then descriptions
-                else loopMain descriptions'
-            where descriptions' = main descriptions
+
         selectExclude :: Selector
         selectExclude exclude phase =
             if elem exclude excludes
                 then id
                 else phase
+
+        dumper :: String -> IOPhase
+        dumper =
+            if null dumpPrefix
+                then const return
+                else fileDumper dumpPrefix
+
+        -- add debug dumping to a phase
+        step :: String -> Phase -> IOPhase
+        step key = (dumper key .)
+
+        -- add convergence and debug dumping to a phase
+        loop :: Int -> String -> Phase -> IOPhase
+        loop idx key phase files =
+            if files == files'
+                then return files
+                else dumper key' files' >>= loop (idx + 1) key phase
+            where
+                files' = phase files
+                key' = key ++ "_" ++ show idx
+
+-- pass through dumper which writes ASTs to a file
+fileDumper :: String -> String -> IOPhase
+fileDumper prefix key files = do
+    let path = prefix ++ key ++ ".sv"
+    let output = show $ concat files
+    writeFile path output
+    return files
diff --git a/src/Job.hs b/src/Job.hs
index 50e05c0..c23be4e 100644
--- a/src/Job.hs
+++ b/src/Job.hs
@@ -44,6 +44,7 @@ data Job = Job
     , write :: Write
     , writeRaw :: String
     , oversizedNumbers :: Bool
+    , dumpPrefix :: FilePath
     } deriving (Typeable, Data)
 
 version :: String
@@ -76,6 +77,9 @@ defaultJob = Job
         &= help ("Disable standard-imposed 32-bit limit on unsized number"
             ++ " literals (e.g., 'h1_ffff_ffff, 4294967296)")
         &= groupname "Other"
+    , dumpPrefix = def &= name "dump-prefix" &= explicit &= typ "PATH"
+        &= help ("Create intermediate output files with the given path prefix;"
+            ++ " used for internal debugging")
     }
     &= program "sv2v"
     &= summary ("sv2v " ++ version)
diff --git a/src/sv2v.hs b/src/sv2v.hs
index 427e992..1fb48d8 100644
--- a/src/sv2v.hs
+++ b/src/sv2v.hs
@@ -89,9 +89,9 @@ main = do
             exitFailure
         Right asts -> do
             -- convert the files if requested
-            let asts' = if passThrough job
-                            then asts
-                            else convert (exclude job) asts
+            asts' <- if passThrough job
+                        then return asts
+                        else convert (dumpPrefix job) (exclude job) asts
             emptyWarnings (concat asts) (concat asts')
             -- write the converted files out
             writeOutput (write job) (files job) asts'