Hoopl: remove dependency on Hoopl package

This copies the subset of Hoopl's functionality needed by GHC to
`cmm/Hoopl` and removes the dependency on the Hoopl package.

The main motivation for this change is the confusing/noisy interface
between GHC and Hoopl:
- Hoopl has `Label` which is GHC's `BlockId` but different than
  GHC's `CLabel`
- Hoopl has `Unique` which is different than GHC's `Unique`
- Hoopl has `Unique{Map,Set}` which are different than GHC's
  `Uniq{FM,Set}`
- GHC has its own specialized copy of `Dataflow`, so `cmm/Hoopl` is
  needed just to filter the exposed functions (filter out some of the
  Hoopl's and add the GHC ones)
With this change, we'll be able to simplify this significantly.
It'll also be much easier to do invasive changes (Hoopl is a public
package on Hackage with users that depend on the current behavior)

This should introduce no changes in functionality - it merely
copies the relevant code.

Signed-off-by: Michal Terepeta <michal.terepeta@gmail.com>

Test Plan: ./validate

Reviewers: austin, bgamari, simonmar

Reviewed By: bgamari, simonmar

Subscribers: simonpj, kavon, rwbarton, thomie

Differential Revision: https://phabricator.haskell.org/D3616

3 files changed, 6 insertions, 3 deletions

diff --git a/compiler/nativeGen/PPC/CodeGen.hs b/compiler/nativeGen/PPC/CodeGen.hs
index a1a205bb95..1e88a1d025 100644
--- a/compiler/nativeGen/PPC/CodeGen.hs
+++ b/compiler/nativeGen/PPC/CodeGen.hs
@@ -46,7 +46,8 @@ import Cmm
 import CmmUtils
 import CmmSwitch
 import CLabel
-import Hoopl
+import Hoopl.Block
+import Hoopl.Graph
 
 -- The rest:
 import OrdList
diff --git a/compiler/nativeGen/PPC/Instr.hs b/compiler/nativeGen/PPC/Instr.hs
index b8b5043d96..eb179c5a99 100644
--- a/compiler/nativeGen/PPC/Instr.hs
+++ b/compiler/nativeGen/PPC/Instr.hs
@@ -33,7 +33,8 @@ import Reg
 
 import CodeGen.Platform
 import BlockId
-import Hoopl
+import Hoopl.Collections
+import Hoopl.Label
 import DynFlags
 import Cmm
 import CmmInfo
diff --git a/compiler/nativeGen/PPC/Ppr.hs b/compiler/nativeGen/PPC/Ppr.hs
index 7f30c5b7ee..63d01c3913 100644
--- a/compiler/nativeGen/PPC/Ppr.hs
+++ b/compiler/nativeGen/PPC/Ppr.hs
@@ -20,7 +20,8 @@ import RegClass
 import TargetReg
 
 import Cmm hiding (topInfoTable)
-import Hoopl
+import Hoopl.Collections
+import Hoopl.Label
 
 import CLabel