[PATCH] D108792: [M68k] Update pointer data layout

[Ricky Taylor via Phabricator via cfe-commits]

This revision was landed with ongoing or failed builds.
This revision was automatically updated to reflect the committed changes.
Closed by commit rG8d3f112f0cdb: [M68k] Update pointer data layout (authored by ricky26).

Changed prior to commit:
  https://reviews.llvm.org/D108792?vs=368995&id=369064#toc

Repository:
  rG LLVM Github Monorepo

CHANGES SINCE LAST ACTION
  https://reviews.llvm.org/D108792/new/

https://reviews.llvm.org/D108792

Files:
  clang/lib/Basic/Targets/M68k.cpp
  llvm/lib/Target/M68k/M68kTargetMachine.cpp


Index: llvm/lib/Target/M68k/M68kTargetMachine.cpp
===================================================================
--- llvm/lib/Target/M68k/M68kTargetMachine.cpp
+++ llvm/lib/Target/M68k/M68kTargetMachine.cpp
@@ -49,10 +49,14 @@
   // FIXME how to wire it with the used object format?
   Ret += "-m:e";
 
-  // M68k pointers are always 32 bit wide even for 16 bit cpus
-  Ret += "-p:32:32";
-
-  // M68k requires i8 to align on 2 byte boundry
+  // M68k pointers are always 32 bit wide even for 16-bit CPUs.
+  // The ABI only specifies 16-bit alignment.
+  // On at least the 68020+ with a 32-bit bus, there is a performance benefit
+  // to having 32-bit alignment.
+  Ret += "-p:32:16:32";
+
+  // Bytes do not require special alignment, words are word aligned and
+  // long words are word aligned at minimum.
   Ret += "-i8:8:8-i16:16:16-i32:16:32";
 
   // FIXME no floats at the moment
Index: clang/lib/Basic/Targets/M68k.cpp
===================================================================
--- clang/lib/Basic/Targets/M68k.cpp
+++ clang/lib/Basic/Targets/M68k.cpp
@@ -37,8 +37,8 @@
   // FIXME how to wire it with the used object format?
   Layout += "-m:e";
 
-  // M68k pointers are always 32 bit wide even for 16 bit cpus
-  Layout += "-p:32:32";
+  // M68k pointers are always 32 bit wide even for 16-bit CPUs
+  Layout += "-p:32:16:32";
 
   // M68k integer data types
   Layout += "-i8:8:8-i16:16:16-i32:16:32";


-------------- next part --------------
A non-text attachment was scrubbed...
Name: D108792.369064.patch
Type: text/x-patch
Size: 1432 bytes
Desc: not available
URL: <http://lists.llvm.org/pipermail/cfe-commits/attachments/20210827/ab38d4eb/attachment.bin>