Added a couple of new sub-reason codes to OS_ReadSysInfo 6;

  Optimised the default IrqV handler.
Detail:
  * OS_ReadSysInfo 6 tells grubby programs lots of grubby info. This
    has been extended to include:

      18 - relocated base of OS SWI despatch table
      19 - relocated base of IRQ device head nodes
      20 - relocated end of IRQ device head nodes
      21 - top of the IRQ stack

    These values are known to be useful for debugging purposes.

  * The default IrqV handler gets the device number times three on
    entry in R0. It then went through a loop subtracting three and
    incrementing a counter to divide by three.

    This has been replaced by four ARM instructions which should
    give the same results (three to divide by three and one to set
    R0 to zero - as the old code did).

    If the device number is outside the range 0..31, the new code
    may produce inaccurate results, but this should not happen.
Admin:
  Not tested ;)

Version 5.43. Tagged as 'Kernel-5_43'

VersionASM

@@ -11,14 +11,14 @@
                         GBLS    Module_HelpVersion
                         GBLS    Module_ComponentName
                         GBLS    Module_ComponentPath
-Module_MajorVersion     SETS    "5.42"
-Module_Version          SETA    542
+Module_MajorVersion     SETS    "5.43"
+Module_Version          SETA    543
 Module_MinorVersion     SETS    ""
-Module_Date             SETS    "10 Apr 2001"
-Module_ApplicationDate2 SETS    "10-Apr-01"
-Module_ApplicationDate4 SETS    "10-Apr-2001"
+Module_Date             SETS    "25 May 2001"
+Module_ApplicationDate2 SETS    "25-May-01"
+Module_ApplicationDate4 SETS    "25-May-2001"
 Module_ComponentName    SETS    "Kernel"
 Module_ComponentPath    SETS    "RiscOS/Sources/Kernel"
-Module_FullVersion      SETS    "5.42"
-Module_HelpVersion      SETS    "5.42 (10 Apr 2001)"
+Module_FullVersion      SETS    "5.43"
+Module_HelpVersion      SETS    "5.43 (25 May 2001)"
                         END

VersionNum

-/* (5.42)
+/* (5.43)
  *
  * This file is automatically maintained by srccommit, do not edit manually.
  *
  */
-#define Module_MajorVersion_CMHG        5.42
+#define Module_MajorVersion_CMHG        5.43
 #define Module_MinorVersion_CMHG        
-#define Module_Date_CMHG                10 Apr 2001
+#define Module_Date_CMHG                25 May 2001
 
-#define Module_MajorVersion             "5.42"
-#define Module_Version                  542
+#define Module_MajorVersion             "5.43"
+#define Module_Version                  543
 #define Module_MinorVersion             ""
-#define Module_Date                     "10 Apr 2001"
+#define Module_Date                     "25 May 2001"
 
-#define Module_ApplicationDate2         "10-Apr-01"
-#define Module_ApplicationDate4         "10-Apr-2001"
+#define Module_ApplicationDate2         "25-May-01"
+#define Module_ApplicationDate4         "25-May-2001"
 
 #define Module_ComponentName            "Kernel"
 #define Module_ComponentPath            "RiscOS/Sources/Kernel"
 
-#define Module_FullVersion              "5.42"
-#define Module_HelpVersion              "5.42 (10 Apr 2001)"
+#define Module_FullVersion              "5.43"
+#define Module_HelpVersion              "5.43 (25 May 2001)"

s/Middle

@@ -1691,25 +1691,29 @@ MachineAddressNVRAMError
         ExitSWIHandler
 
 osri6_table
-    DCD  CamEntriesPointer        ;0
-    DCD  MaxCamEntry              ;1
-    DCD  PageFlags_Unavailable    ;2
-    DCD  PhysRamTable             ;3
-    DCD  ARMA_Cleaner_flipflop    ;4
-    DCD  TickNodeChain            ;5
-    DCD  ROMModuleChain           ;6
-    DCD  DAList                   ;7
-    DCD  AppSpaceDANode           ;8
-    DCD  Module_List              ;9
-    DCD  ModuleSHT_Entries        ;10
-    DCD  ModuleSWI_HashTab        ;11
-    DCD  IOSystemType             ;12
-    DCD  L1PT                     ;13
-    DCD  L2PT                     ;14
-    DCD  UNDSTK                   ;15
-    DCD  SVCSTK                   ;16
-    DCD  SysHeapStart             ;17
-osri6_maxvalue * 17
+    DCD  CamEntriesPointer                            ;0
+    DCD  MaxCamEntry                                  ;1
+    DCD  PageFlags_Unavailable                        ;2
+    DCD  PhysRamTable                                 ;3
+    DCD  ARMA_Cleaner_flipflop                        ;4
+    DCD  TickNodeChain                                ;5
+    DCD  ROMModuleChain                               ;6
+    DCD  DAList                                       ;7
+    DCD  AppSpaceDANode                               ;8
+    DCD  Module_List                                  ;9
+    DCD  ModuleSHT_Entries                            ;10
+    DCD  ModuleSWI_HashTab                            ;11
+    DCD  IOSystemType                                 ;12
+    DCD  L1PT                                         ;13
+    DCD  L2PT                                         ;14
+    DCD  UNDSTK                                       ;15
+    DCD  SVCSTK                                       ;16
+    DCD  SysHeapStart                                 ;17
+    DCD  JTABLE-SWIRelocation                         ;18 - relocated base of OS SWI despatch table
+    DCD  DefaultIRQ1V+(Devices-DefaultIRQ1Vcode)      ;19 - relocated base of IRQ device head nodes
+    DCD  DefaultIRQ1V+(DeviceTables-DefaultIRQ1Vcode) ;20 - relocated end of IRQ device head nodes
+    DCD  IRQSTK                                       ;21 - top of the IRQ stack
+osri6_maxvalue * (.-4-osri6_table) :SHR: 2
 
 
 ; OS_ReadSysInfo 7  - read 32-bit Abort information for last unexpected abort

s/NewIRQs

@@ -1060,12 +1060,13 @@ NOIRQ ROUT
  MOV r10, #VIDC
  STR r14, [r10]
  ]
-01      SUBS    r0, r0, #3
-        ADDGE   r12, r12, #1
-        BGT     %BT01                   ; r12 := r0 DIV 3
+        ADD     R12, R0, R0, LSL #3      ; r12 := 9*R0
+        ADD     R12, R12, R0, LSL #1     ; r12 := 11*R0
+        MOV     R12, R12, LSR #5         ; r12 := r0/3
 
         CMP     R12, #8
         MOVLO   R0, #IOCIRQMSKA
+        MOVHS   R0, #0
         BLO     %FT03
 
         CMP     R12, #16