Add support for CPU features (i.e., bugs) and workarounds.

This is just the framework to identify the needed workarounds. They are not actually implemented.

llvm-svn: 77902

llvm/lib/Target/Blackfin/Blackfin.td

@@ -20,8 +20,53 @@ include "llvm/Target/Target.td"
 // Blackfin Subtarget features.
 //===----------------------------------------------------------------------===//
 
-def FeatureSSYNC : SubtargetFeature<"ssync","ssyncWorkaround", "true",
+def FeatureSDRAM : SubtargetFeature<"sdram", "sdram", "true",
-                                    "Work around SSYNC bugs">;
+    "Build for SDRAM">;
+
+def FeatureICPLB : SubtargetFeature<"icplb", "icplb", "true",
+    "Assume instruction cache lookaside buffers are enabled at runtime">;
+
+//===----------------------------------------------------------------------===//
+// Bugs in the silicon becomes workarounds in the compiler.
+// See http://www.analog.com/ for the full list of IC anomalies.
+//===----------------------------------------------------------------------===//
+
+def WA_MI_SHIFT : SubtargetFeature<"mi-shift-anomaly","wa_mi_shift", "true",
+    "Work around 05000074 - "
+    "Multi-Issue Instruction with dsp32shiftimm and P-reg Store">;
+
+def WA_CSYNC : SubtargetFeature<"csync-anomaly","wa_csync", "true",
+    "Work around 05000244 - "
+    "If I-Cache Is On, CSYNC/SSYNC/IDLE Around Change of Control">;
+
+def WA_SPECLD : SubtargetFeature<"specld-anomaly","wa_specld", "true",
+    "Work around 05000245 - "
+    "Access in the Shadow of a Conditional Branch">;
+
+def WA_HWLOOP : SubtargetFeature<"hwloop-anomaly","wa_hwloop", "true",
+    "Work around 05000257 - "
+    "Interrupt/Exception During Short Hardware Loop">;
+
+def WA_MMR_STALL : SubtargetFeature<"mmr-stall-anomaly","wa_mmr_stall", "true",
+    "Work around 05000283 - "
+    "System MMR Write Is Stalled Indefinitely when Killed">;
+
+def WA_LCREGS : SubtargetFeature<"lcregs-anomaly","wa_lcregs", "true",
+    "Work around 05000312 - "
+    "SSYNC, CSYNC, or Loads to LT, LB and LC Registers Are Interrupted">;
+
+def WA_KILLED_MMR : SubtargetFeature<"killed-mmr-anomaly",
+                                     "wa_killed_mmr", "true",
+    "Work around 05000315 - "
+    "Killed System MMR Write Completes Erroneously on Next System MMR Access">;
+
+def WA_RETS : SubtargetFeature<"rets-anomaly", "wa_rets", "true",
+    "Work around 05000371 - "
+    "Possible RETS Register Corruption when Subroutine Is under 5 Cycles">;
+
+def WA_IND_CALL : SubtargetFeature<"ind-call-anomaly", "wa_ind_call", "true",
+    "Work around 05000426 - "
+    "Speculative Fetches of Indirect-Pointer Instructions">;
 
 //===----------------------------------------------------------------------===//
 // Register File, Calling Conv, Instruction Descriptions
@@ -37,10 +82,114 @@ def BlackfinInstrInfo : InstrInfo {}
 // Blackfin processors supported.
 //===----------------------------------------------------------------------===//
 
-class Proc<string Name, list<SubtargetFeature> Features>
+class Proc<string Name, string Suffix, list<SubtargetFeature> Features>
- : Processor<Name, NoItineraries, Features>;
+ : Processor<!strconcat(Name, Suffix), NoItineraries, Features>;
 
-def : Proc<"generic", [FeatureSSYNC]>;
+def : Proc<"generic", "", []>;
+
+multiclass Core<string Name,string Suffix,
+                list<SubtargetFeature> Features> {
+  def : Proc<Name, Suffix, Features>;
+  def : Proc<Name, "", Features>;
+  def : Proc<Name, "-none", []>;
+}
+
+multiclass CoreEdinburgh<string Name>
+      : Core<Name, "-0.6", [WA_MI_SHIFT, WA_SPECLD, WA_LCREGS]> {
+  def : Proc<Name, "-0.5",
+        [WA_MI_SHIFT, WA_SPECLD, WA_MMR_STALL, WA_LCREGS, WA_KILLED_MMR,
+         WA_RETS]>;
+  def : Proc<Name, "-0.4",
+        [WA_MI_SHIFT, WA_CSYNC, WA_SPECLD, WA_HWLOOP, WA_MMR_STALL, WA_LCREGS,
+         WA_KILLED_MMR, WA_RETS]>;
+  def : Proc<Name, "-0.3",
+        [WA_MI_SHIFT, WA_CSYNC, WA_SPECLD, WA_HWLOOP, WA_MMR_STALL, WA_LCREGS,
+         WA_KILLED_MMR, WA_RETS]>;
+  def : Proc<Name, "-any",
+        [WA_MI_SHIFT, WA_CSYNC, WA_SPECLD, WA_HWLOOP, WA_MMR_STALL, WA_LCREGS,
+         WA_KILLED_MMR, WA_RETS]>;
+}
+multiclass CoreBraemar<string Name>
+       : Core<Name, "-0.3",
+         [WA_MI_SHIFT, WA_SPECLD, WA_LCREGS, WA_RETS, WA_IND_CALL]> {
+  def  : Proc<Name, "-0.2",
+         [WA_MI_SHIFT, WA_CSYNC, WA_SPECLD, WA_HWLOOP, WA_MMR_STALL, WA_LCREGS,
+          WA_KILLED_MMR, WA_RETS, WA_IND_CALL]>;
+  def  : Proc<Name, "-any",
+         [WA_MI_SHIFT, WA_CSYNC, WA_SPECLD, WA_HWLOOP, WA_MMR_STALL, WA_LCREGS,
+          WA_KILLED_MMR, WA_RETS, WA_IND_CALL]>;
+}
+multiclass CoreStirling<string Name>
+      : Core<Name, "-0.5", [WA_MI_SHIFT, WA_SPECLD, WA_IND_CALL]> {
+  def : Proc<Name, "-0.4",
+        [WA_MI_SHIFT, WA_SPECLD, WA_LCREGS, WA_RETS, WA_IND_CALL]>;
+  def : Proc<Name, "-0.3",
+        [WA_MI_SHIFT, WA_SPECLD, WA_MMR_STALL, WA_LCREGS, WA_KILLED_MMR,
+         WA_RETS, WA_IND_CALL]>;
+  def : Proc<Name, "-any",
+        [WA_MI_SHIFT, WA_SPECLD, WA_MMR_STALL, WA_LCREGS, WA_KILLED_MMR,
+         WA_RETS, WA_IND_CALL]>;
+}
+multiclass CoreMoab<string Name>
+      : Core<Name, "-0.3", [WA_MI_SHIFT, WA_SPECLD, WA_IND_CALL]> {
+  def : Proc<Name, "-0.2", [WA_MI_SHIFT, WA_SPECLD, WA_IND_CALL]>;
+  def : Proc<Name, "-0.1", [WA_MI_SHIFT, WA_SPECLD, WA_RETS, WA_IND_CALL]>;
+  def : Proc<Name, "-0.0",
+        [WA_MI_SHIFT, WA_SPECLD, WA_LCREGS, WA_RETS, WA_IND_CALL]>;
+  def : Proc<Name, "-any",
+        [WA_MI_SHIFT, WA_SPECLD, WA_LCREGS, WA_RETS, WA_IND_CALL]>;
+}
+multiclass CoreTeton<string Name>
+      : Core<Name, "-0.5",
+        [WA_MI_SHIFT, WA_SPECLD, WA_MMR_STALL, WA_LCREGS, WA_KILLED_MMR,
+         WA_RETS, WA_IND_CALL]> {
+  def : Proc<Name, "-0.3",
+        [WA_MI_SHIFT, WA_CSYNC, WA_SPECLD, WA_HWLOOP, WA_MMR_STALL, WA_LCREGS,
+         WA_KILLED_MMR, WA_RETS, WA_IND_CALL]>;
+  def : Proc<Name, "-any",
+        [WA_MI_SHIFT, WA_CSYNC, WA_SPECLD, WA_HWLOOP, WA_MMR_STALL, WA_LCREGS,
+         WA_KILLED_MMR, WA_RETS, WA_IND_CALL]>;
+}
+multiclass CoreKookaburra<string Name>
+      : Core<Name, "-0.2", [WA_MI_SHIFT, WA_SPECLD, WA_IND_CALL]> {
+  def : Proc<Name, "-0.1", [WA_MI_SHIFT, WA_SPECLD, WA_RETS, WA_IND_CALL]>;
+  def : Proc<Name, "-0.0", [WA_MI_SHIFT, WA_SPECLD, WA_RETS, WA_IND_CALL]>;
+  def : Proc<Name, "-any", [WA_MI_SHIFT, WA_SPECLD, WA_RETS, WA_IND_CALL]>;
+}
+multiclass CoreMockingbird<string Name>
+      : Core<Name, "-0.1", [WA_MI_SHIFT, WA_SPECLD, WA_IND_CALL]> {
+  def : Proc<Name, "-0.0", [WA_MI_SHIFT, WA_SPECLD, WA_IND_CALL]>;
+  def : Proc<Name, "-any", [WA_MI_SHIFT, WA_SPECLD, WA_IND_CALL]>;
+}
+multiclass CoreBrodie<string Name>
+      : Core<Name, "-0.1", [WA_MI_SHIFT, WA_SPECLD, WA_IND_CALL]> {
+  def : Proc<Name, "-0.0", [WA_MI_SHIFT, WA_SPECLD, WA_IND_CALL]>;
+  def : Proc<Name, "-any", [WA_MI_SHIFT, WA_SPECLD, WA_IND_CALL]>;
+}
+
+defm BF512 : CoreBrodie<"bf512">;
+defm BF514 : CoreBrodie<"bf514">;
+defm BF516 : CoreBrodie<"bf516">;
+defm BF518 : CoreBrodie<"bf518">;
+defm BF522 : CoreMockingbird<"bf522">;
+defm BF523 : CoreKookaburra<"bf523">;
+defm BF524 : CoreMockingbird<"bf524">;
+defm BF525 : CoreKookaburra<"bf525">;
+defm BF526 : CoreMockingbird<"bf526">;
+defm BF527 : CoreKookaburra<"bf527">;
+defm BF531 : CoreEdinburgh<"bf531">;
+defm BF532 : CoreEdinburgh<"bf532">;
+defm BF533 : CoreEdinburgh<"bf533">;
+defm BF534 : CoreBraemar<"bf534">;
+defm BF536 : CoreBraemar<"bf536">;
+defm BF537 : CoreBraemar<"bf537">;
+defm BF538 : CoreStirling<"bf538">;
+defm BF539 : CoreStirling<"bf539">;
+defm BF542 : CoreMoab<"bf542">;
+defm BF544 : CoreMoab<"bf544">;
+defm BF548 : CoreMoab<"bf548">;
+defm BF549 : CoreMoab<"bf549">;
+defm BF561 : CoreTeton<"bf561">;
 
 //===----------------------------------------------------------------------===//
 // Declare the target which we are implementing

llvm/lib/Target/Blackfin/BlackfinSubtarget.cpp

@@ -18,9 +18,20 @@ using namespace llvm;
 
 BlackfinSubtarget::BlackfinSubtarget(const TargetMachine &TM,
                                      const Module &M,
-                                     const std::string &FS) {
+                                     const std::string &FS)
+  : sdram(false),
+    icplb(false),
+    wa_mi_shift(false),
+    wa_csync(false),
+    wa_specld(false),
+    wa_mmr_stall(false),
+    wa_lcregs(false),
+    wa_hwloop(false),
+    wa_ind_call(false),
+    wa_killed_mmr(false),
+    wa_rets(false)
+{
   std::string CPU = "generic";
-
   // Parse features string.
   ParseSubtargetFeatures(FS, CPU);
 }

llvm/lib/Target/Blackfin/BlackfinSubtarget.h

@@ -23,7 +23,17 @@ namespace llvm {
   class Module;
 
   class BlackfinSubtarget : public TargetSubtarget {
-    bool ssyncWorkaround;
+    bool sdram;
+    bool icplb;
+    bool wa_mi_shift;
+    bool wa_csync;
+    bool wa_specld;
+    bool wa_mmr_stall;
+    bool wa_lcregs;
+    bool wa_hwloop;
+    bool wa_ind_call;
+    bool wa_killed_mmr;
+    bool wa_rets;
   public:
     BlackfinSubtarget(const TargetMachine &TM, const Module &M,
                       const std::string &FS);

llvm/lib/Target/Blackfin/README.txt

@@ -170,3 +170,75 @@ Stores:
 | I--        | * |   | *    | *    |     |
 | I++M       | * |   |      |      |     |
 
+* Workarounds and features
+Blackfin CPUs have bugs. Each model comes in a number of silicon revisions with
+different bugs. We learn about the CPU model from the -mcpu switch.
+
+** Interpretation of -mcpu value
+- -mcpu=bf527 refers to the latest known BF527 revision
+- -mcpu=bf527-0.2 refers to silicon rev. 0.2
+- -mcpu=bf527-any refers to all known revisions
+- -mcpu=bf527-none disables all workarounds
+
+The -mcpu setting affects the __SILICON_REVISION__ macro and enabled workarounds:
+
+| -mcpu      | __SILICON_REVISION__ | Workarounds        |
+|------------+----------------------+--------------------|
+| bf527      | Def Latest           | Specific to latest |
+| bf527-1.3  | Def 0x0103           | Specific to 1.3    |
+| bf527-any  | Def 0xffff           | All bf527-x.y      |
+| bf527-none | Undefined            | None               |
+
+These are the known cores and revisions:
+
+| Core        | Silicon            | Processors              |
+|-------------+--------------------+-------------------------|
+| Edinburgh   | 0.3, 0.4, 0.5, 0.6 | BF531 BF532 BF533       |
+| Braemar     | 0.2, 0.3           | BF534 BF536 BF537       |
+| Stirling    | 0.3, 0.4, 0.5      | BF538 BF539             |
+| Moab        | 0.0, 0.1, 0.2      | BF542 BF544 BF548 BF549 |
+| Teton       | 0.3, 0.5           | BF561                   |
+| Kookaburra  | 0.0, 0.1, 0.2      | BF523 BF525 BF527       |
+| Mockingbird | 0.0, 0.1           | BF522 BF524 BF526       |
+| Brodie      | 0.0, 0.1           | BF512 BF514 BF516 BF518 |
+
+
+** Compiler implemented workarounds
+Most workarounds are implemented in header files and source code using the
+__ADSPBF527__ macros. A few workarounds require compiler support.
+
+|  Anomaly | Macro                          | GCC Switch       |
+|----------+--------------------------------+------------------|
+|      Any | __WORKAROUNDS_ENABLED          |                  |
+| 05000074 | WA_05000074                    |                  |
+| 05000244 | __WORKAROUND_SPECULATIVE_SYNCS | -mcsync-anomaly  |
+| 05000245 | __WORKAROUND_SPECULATIVE_LOADS | -mspecld-anomaly |
+| 05000257 | WA_05000257                    |                  |
+| 05000283 | WA_05000283                    |                  |
+| 05000312 | WA_LOAD_LCREGS                 |                  |
+| 05000315 | WA_05000315                    |                  |
+| 05000371 | __WORKAROUND_RETS              |                  |
+| 05000426 | __WORKAROUND_INDIRECT_CALLS    | Not -micplb      |
+
+** GCC feature switches
+| Switch                    | Description                            |
+|---------------------------+----------------------------------------|
+| -msim                     | Use simulator runtime                  |
+| -momit-leaf-frame-pointer | Omit frame pointer for leaf functions  |
+| -mlow64k                  |                                        |
+| -mcsync-anomaly           |                                        |
+| -mspecld-anomaly          |                                        |
+| -mid-shared-library       |                                        |
+| -mleaf-id-shared-library  |                                        |
+| -mshared-library-id=      |                                        |
+| -msep-data                | Enable separate data segment           |
+| -mlong-calls              | Use indirect calls                     |
+| -mfast-fp                 |                                        |
+| -mfdpic                   |                                        |
+| -minline-plt              |                                        |
+| -mstack-check-l1          | Do stack checking in L1 scratch memory |
+| -mmulticore               | Enable multicore support               |
+| -mcorea                   | Build for Core A                       |
+| -mcoreb                   | Build for Core B                       |
+| -msdram                   | Build for SDRAM                        |
+| -micplb                   | Assume ICPLBs are enabled at runtime.  |