ArmPkg: Stop using ArmDisassemblerLib

ArmDisassemblerLib is used to pretty print the instruction that
triggered an unhandled exception, but it was never implemented for
AARCH64, and according to the existing file comment, Thumb2 support
(which is used predominantly when building EDK2 for 32-bit ARM due to
its smaller size) is incomplete.

The DEBUG diagnostics that are produced on an unhandled exception are
generally sufficient to dump the entire executable that triggered it,
and so this disassembly is of limited value, especially because it
doesn't work on AARCH64.

So let's start getting rid of it, by dropping references to it in code
and in the various .INF and .DSC files. Once out-of-tree platforms have
been allowed to catch up, we can remove the library implementation and
its class definition entirely.

Signed-off-by: Ard Biesheuvel <ardb@kernel.org>

5 files changed, 1 insertions, 35 deletions

diff --git a/ArmPkg/ArmPkg.dsc b/ArmPkg/ArmPkg.dsc
index 061d9d60dc..7e8def29ca 100644
--- a/ArmPkg/ArmPkg.dsc
+++ b/ArmPkg/ArmPkg.dsc
@@ -70,7 +70,6 @@
   ArmGenericTimerCounterLib|ArmPkg/Library/ArmGenericTimerPhyCounterLib/ArmGenericTimerPhyCounterLib.inf

   ArmSvcLib|ArmPkg/Library/ArmSvcLib/ArmSvcLib.inf

   ArmSmcLib|ArmPkg/Library/ArmSmcLib/ArmSmcLib.inf

-  ArmDisassemblerLib|ArmPkg/Library/ArmDisassemblerLib/ArmDisassemblerLib.inf

   OpteeLib|ArmPkg/Library/OpteeLib/OpteeLib.inf

 

   UefiApplicationEntryPoint|MdePkg/Library/UefiApplicationEntryPoint/UefiApplicationEntryPoint.inf

diff --git a/ArmPkg/Drivers/ArmCrashDumpDxe/ArmCrashDumpDxe.dsc b/ArmPkg/Drivers/ArmCrashDumpDxe/ArmCrashDumpDxe.dsc
index 28ebe68b41..f93d31776f 100644
--- a/ArmPkg/Drivers/ArmCrashDumpDxe/ArmCrashDumpDxe.dsc
+++ b/ArmPkg/Drivers/ArmCrashDumpDxe/ArmCrashDumpDxe.dsc
@@ -26,7 +26,6 @@
   gEfiMdePkgTokenSpaceGuid.PcdDebugPropertyMask|0x27

 

 [LibraryClasses]

-  ArmDisassemblerLib|ArmPkg/Library/ArmDisassemblerLib/ArmDisassemblerLib.inf

   BaseLib|MdePkg/Library/BaseLib/BaseLib.inf

   BaseMemoryLib|MdePkg/Library/BaseMemoryLib/BaseMemoryLib.inf

   DebugLib|MdePkg/Library/UefiDebugLibConOut/UefiDebugLibConOut.inf

diff --git a/ArmPkg/Library/DefaultExceptionHandlerLib/AArch64/DefaultExceptionHandler.c b/ArmPkg/Library/DefaultExceptionHandlerLib/AArch64/DefaultExceptionHandler.c
index 9b5adeaf89..5f9bcf7966 100644
--- a/ArmPkg/Library/DefaultExceptionHandlerLib/AArch64/DefaultExceptionHandler.c
+++ b/ArmPkg/Library/DefaultExceptionHandlerLib/AArch64/DefaultExceptionHandler.c
@@ -14,7 +14,6 @@
 #include <Library/DebugLib.h>

 #include <Library/PeCoffGetEntryPointLib.h>

 #include <Library/PrintLib.h>

-#include <Library/ArmDisassemblerLib.h>

 #include <Library/SerialPortLib.h>

 #include <Library/UefiBootServicesTableLib.h>

 

diff --git a/ArmPkg/Library/DefaultExceptionHandlerLib/Arm/DefaultExceptionHandler.c b/ArmPkg/Library/DefaultExceptionHandlerLib/Arm/DefaultExceptionHandler.c
index accad647d6..50e4205c23 100644
--- a/ArmPkg/Library/DefaultExceptionHandlerLib/Arm/DefaultExceptionHandler.c
+++ b/ArmPkg/Library/DefaultExceptionHandlerLib/Arm/DefaultExceptionHandler.c
@@ -13,7 +13,6 @@
 #include <Library/DebugLib.h>

 #include <Library/PeCoffGetEntryPointLib.h>

 #include <Library/PrintLib.h>

-#include <Library/ArmDisassemblerLib.h>

 #include <Library/SerialPortLib.h>

 #include <Library/UefiBootServicesTableLib.h>

 #include <Library/UefiLib.h>

@@ -210,9 +209,6 @@ DefaultExceptionHandler (
   UINT32   DfsrStatus;

   UINT32   IfsrStatus;

   BOOLEAN  DfsrWrite;

-  UINT32   PcAdjust;

-

-  PcAdjust = 0;

 

   CharCount = AsciiSPrint (

                 Buffer,

@@ -233,11 +229,7 @@ DefaultExceptionHandler (
   UINT32  ImageBase;

   UINT32  PeCoffSizeOfHeader;

   UINT32  Offset;

-  CHAR8   CpsrStr[CPSR_STRING_SIZE];    // char per bit. Lower 5-bits are mode

-                                        // that is a 3 char string

-  CHAR8   Buffer[80];

-  UINT8   *DisAsm;

-  UINT32  ItBlock;

+  CHAR8   CpsrStr[CPSR_STRING_SIZE];

 

   CpsrString (SystemContext.SystemContextArm->CPSR, CpsrStr);

   DEBUG ((DEBUG_ERROR, "%a\n", CpsrStr));

@@ -256,25 +248,6 @@ DefaultExceptionHandler (
     // get the offset that matches the link map.

     //

     DEBUG ((DEBUG_ERROR, "loaded at 0x%08x (PE/COFF offset) 0x%x (ELF or Mach-O offset) 0x%x", ImageBase, Offset, Offset - PeCoffSizeOfHeader));

-

-    // If we come from an image it is safe to show the instruction. We know it should not fault

-    DisAsm  = (UINT8 *)(UINTN)SystemContext.SystemContextArm->PC;

-    ItBlock = 0;

-    DisassembleInstruction (&DisAsm, (SystemContext.SystemContextArm->CPSR & BIT5) == BIT5, TRUE, &ItBlock, Buffer, sizeof (Buffer));

-    DEBUG ((DEBUG_ERROR, "\n%a", Buffer));

-

-    switch (ExceptionType) {

-      case EXCEPT_ARM_UNDEFINED_INSTRUCTION:

-      case EXCEPT_ARM_SOFTWARE_INTERRUPT:

-      case EXCEPT_ARM_PREFETCH_ABORT:

-      case EXCEPT_ARM_DATA_ABORT:

-        // advance PC past the faulting instruction

-        PcAdjust = (UINTN)DisAsm - SystemContext.SystemContextArm->PC;

-        break;

-

-      default:

-        break;

-    }

   }

 

   DEBUG_CODE_END ();

@@ -312,7 +285,4 @@ DefaultExceptionHandler (
   // Clear the error registers that we have already displayed incase some one wants to keep going

   SystemContext.SystemContextArm->DFSR = 0;

   SystemContext.SystemContextArm->IFSR = 0;

-

-  // If some one is stepping past the exception handler adjust the PC to point to the next instruction

-  SystemContext.SystemContextArm->PC += PcAdjust;

 }

diff --git a/ArmPkg/Library/DefaultExceptionHandlerLib/DefaultExceptionHandlerLib.inf b/ArmPkg/Library/DefaultExceptionHandlerLib/DefaultExceptionHandlerLib.inf
index c7d31f6408..30291a4663 100644
--- a/ArmPkg/Library/DefaultExceptionHandlerLib/DefaultExceptionHandlerLib.inf
+++ b/ArmPkg/Library/DefaultExceptionHandlerLib/DefaultExceptionHandlerLib.inf
@@ -35,7 +35,6 @@
   PrintLib

   DebugLib

   PeCoffGetEntryPointLib

-  ArmDisassemblerLib

   SerialPortLib

   UefiBootServicesTableLib