[AVR] Fix I/O instructions on XMEGA

dylanmckay · dylanmckay · commit 93ee4da19cff · 2020-06-24T01:24:15.000+12:00
Summary: On XMEGA, I/O address space is same as data address space - there is no 0x20 offset, because CPU General Purpose Registers are not mapped in data address space. From https://en.wikipedia.org/wiki/AVR_microcontrollers > In the XMEGA variant, the working register file is not mapped into the data address space; as such, it is not possible to treat any of the XMEGA's working registers as though they were SRAM. Instead, the I/O registers are mapped into the data address space starting at the very beginning of the address space. Reviewers: dylanmckay Reviewed By: dylanmckay Subscribers: hiraditya, Jim, llvm-commits Tags: #llvm Differential Revision: https://reviews.llvm.org/D77207 Patch by Vlastimil Labsky.
diff --git a/llvm/lib/Target/AVR/AVRDevices.td b/llvm/lib/Target/AVR/AVRDevices.td
@@ -121,6 +121,11 @@ def FeatureTinyEncoding   : SubtargetFeature<"tinyencoding",
                                   "The device has Tiny core specific "
                                   "instruction encodings">;
 
+// The device has CPU registers mapped in data address space
+def FeatureMMR : SubtargetFeature<"memmappedregs", "m_hasMemMappedGPR",
+                                  "true", "The device has CPU registers "
+                                  "mapped in data address space">;
+
 class ELFArch<string name>  : SubtargetFeature<"", "ELFArch",
                                     !strconcat("ELF::",name), "">;
 
@@ -152,7 +157,7 @@ def ELFArchXMEGA7  : ELFArch<"EF_AVR_ARCH_XMEGA7">;
 // device should have.
 def FamilyAVR0           : Family<"avr0", []>;
 
-def FamilyAVR1           : Family<"avr1", [FamilyAVR0, FeatureLPM]>;
+def FamilyAVR1           : Family<"avr1", [FamilyAVR0, FeatureLPM, FeatureMMR]>;
 
 def FamilyAVR2           : Family<"avr2",
                                  [FamilyAVR1, FeatureIJMPCALL, FeatureADDSUBIW,
@@ -190,11 +195,14 @@ def FamilyAVR6           : Family<"avr6",
 
 def FamilyTiny           : Family<"avrtiny",
                                  [FamilyAVR0, FeatureBREAK, FeatureSRAM,
-                                  FeatureTinyEncoding]>;
+                                  FeatureTinyEncoding, FeatureMMR]>;
 
 def FamilyXMEGA          : Family<"xmega",
-                                 [FamilyAVR51, FeatureEIJMPCALL, FeatureSPMX,
-                                  FeatureDES]>;
+                                 [FamilyAVR0, FeatureLPM, FeatureIJMPCALL, FeatureADDSUBIW,
+                                  FeatureSRAM, FeatureJMPCALL, FeatureMultiplication,
+                                  FeatureMOVW, FeatureLPMX, FeatureSPM,
+                                  FeatureBREAK, FeatureEIJMPCALL, FeatureSPMX,
+                                  FeatureDES, FeatureELPM, FeatureELPMX]>;
 
 def FamilyXMEGAU         : Family<"xmegau",
                                   [FamilyXMEGA, FeatureRMW]>;
@@ -208,7 +216,7 @@ def FeatureSetSpecial    : FeatureSet<"special",
                                        FeatureLPM, FeatureLPMX, FeatureELPM,
                                        FeatureELPMX, FeatureSPM, FeatureSPMX,
                                        FeatureDES, FeatureRMW,
-                                       FeatureMultiplication, FeatureBREAK]>;
+                                       FeatureMultiplication, FeatureBREAK, FeatureMMR]>;
 
 //===---------------------------------------------------------------------===//
 // AVR microcontrollers supported.
diff --git a/llvm/lib/Target/AVR/AVRInstrInfo.td b/llvm/lib/Target/AVR/AVRInstrInfo.td
@@ -107,7 +107,9 @@ def imm_com8 : Operand<i8> {
 
 def ioaddr_XFORM : SDNodeXForm<imm,
 [{
-  return CurDAG->getTargetConstant(uint8_t(N->getZExtValue()) - 0x20, SDLoc(N), MVT::i8);
+  uint8_t offset = Subtarget->getIORegisterOffset();
+  return CurDAG->getTargetConstant(uint8_t(N->getZExtValue()) - offset,
+                                   SDLoc(N), MVT::i8);
 }]>;
 
 def iobitpos8_XFORM : SDNodeXForm<imm,
@@ -124,20 +126,23 @@ def iobitposn8_XFORM : SDNodeXForm<imm,
 
 def ioaddr8 : PatLeaf<(imm),
 [{
-  uint64_t val = N->getZExtValue();
-  return val >= 0x20 && val < 0x60;
+  uint8_t offset = Subtarget->getIORegisterOffset();
+  uint64_t val = N->getZExtValue() - offset;
+  return val >= 0x0 && val < 0x40;
 }], ioaddr_XFORM>;
 
 def lowioaddr8 : PatLeaf<(imm),
 [{
-  uint64_t val = N->getZExtValue();
-  return val >= 0x20 && val < 0x40;
+  uint8_t offset = Subtarget->getIORegisterOffset();
+  uint64_t val = N->getZExtValue() - offset;
+  return val >= 0x0 && val < 0x20;
 }], ioaddr_XFORM>;
 
 def ioaddr16 : PatLeaf<(imm),
 [{
-  uint64_t val = N->getZExtValue();
-  return val >= 0x20 && val < 0x5f;
+  uint8_t offset = Subtarget->getIORegisterOffset();
+  uint64_t val = N->getZExtValue() - offset;
+  return val >= 0x0 && val < 0x3f;
 }], ioaddr_XFORM>;
 
 def iobitpos8 : PatLeaf<(imm),
diff --git a/llvm/lib/Target/AVR/AVRSubtarget.cpp b/llvm/lib/Target/AVR/AVRSubtarget.cpp
@@ -29,16 +29,16 @@ namespace llvm {
 
 AVRSubtarget::AVRSubtarget(const Triple &TT, const std::string &CPU,
                            const std::string &FS, const AVRTargetMachine &TM)
-    : AVRGenSubtargetInfo(TT, CPU, FS),
-      ELFArch(0),
+    : AVRGenSubtargetInfo(TT, CPU, FS), ELFArch(0),
 
       // Subtarget features
       m_hasSRAM(false), m_hasJMPCALL(false), m_hasIJMPCALL(false),
       m_hasEIJMPCALL(false), m_hasADDSUBIW(false), m_hasSmallStack(false),
-      m_hasMOVW(false), m_hasLPM(false), m_hasLPMX(false),  m_hasELPM(false),
+      m_hasMOVW(false), m_hasLPM(false), m_hasLPMX(false), m_hasELPM(false),
       m_hasELPMX(false), m_hasSPM(false), m_hasSPMX(false), m_hasDES(false),
       m_supportsRMW(false), m_supportsMultiplication(false), m_hasBREAK(false),
-      m_hasTinyEncoding(false), m_FeatureSetDummy(false),
+      m_hasTinyEncoding(false), m_hasMemMappedGPR(false),
+      m_FeatureSetDummy(false),
 
       InstrInfo(), FrameLowering(),
       TLInfo(TM, initializeSubtargetDependencies(CPU, FS, TM)), TSInfo() {
diff --git a/llvm/lib/Target/AVR/AVRSubtarget.h b/llvm/lib/Target/AVR/AVRSubtarget.h
@@ -71,6 +71,9 @@ class AVRSubtarget : public AVRGenSubtargetInfo {
   bool supportsMultiplication() const { return m_supportsMultiplication; }
   bool hasBREAK() const { return m_hasBREAK; }
   bool hasTinyEncoding() const { return m_hasTinyEncoding; }
+  bool hasMemMappedGPR() const { return m_hasMemMappedGPR; }
+
+  uint8_t getIORegisterOffset() const { return hasMemMappedGPR() ? 0x20 : 0x0; }
 
   /// Gets the ELF architecture for the e_flags field
   /// of an ELF object file.
@@ -105,6 +108,7 @@ class AVRSubtarget : public AVRGenSubtargetInfo {
   bool m_supportsMultiplication;
   bool m_hasBREAK;
   bool m_hasTinyEncoding;
+  bool m_hasMemMappedGPR;
 
   // Dummy member, used by FeatureSet's. We cannot have a SubtargetFeature with
   // no variable, so we instead bind pseudo features to this variable.
diff --git a/llvm/test/CodeGen/AVR/features/xmega_io.ll b/llvm/test/CodeGen/AVR/features/xmega_io.ll
@@ -0,0 +1,48 @@
+; RUN: llc -O0 < %s -march=avr -mcpu avrxmega1 | FileCheck %s -check-prefix=XMEGA
+; RUN: llc -O0 < %s -march=avr -mcpu avrxmega2 | FileCheck %s -check-prefix=XMEGA
+; RUN: llc -O0 < %s -march=avr -mcpu avrxmega3 | FileCheck %s -check-prefix=XMEGA
+; RUN: llc -O0 < %s -march=avr -mcpu avrxmega4 | FileCheck %s -check-prefix=XMEGA
+; RUN: llc -O0 < %s -march=avr -mcpu avrxmega5 | FileCheck %s -check-prefix=XMEGA
+; RUN: llc -O0 < %s -march=avr -mcpu avrxmega6 | FileCheck %s -check-prefix=XMEGA
+; RUN: llc -O0 < %s -march=avr -mcpu avrxmega7 | FileCheck %s -check-prefix=XMEGA
+; RUN: llc -O0 < %s -march=avr -mcpu avr2 | FileCheck %s -check-prefix=AVR
+; RUN: llc -O0 < %s -march=avr -mcpu avr25 | FileCheck %s -check-prefix=AVR
+; RUN: llc -O0 < %s -march=avr -mcpu avr3 | FileCheck %s -check-prefix=AVR
+; RUN: llc -O0 < %s -march=avr -mcpu avr31 | FileCheck %s -check-prefix=AVR
+; RUN: llc -O0 < %s -march=avr -mcpu avr35 | FileCheck %s -check-prefix=AVR
+; RUN: llc -O0 < %s -march=avr -mcpu avr4 | FileCheck %s -check-prefix=AVR
+; RUN: llc -O0 < %s -march=avr -mcpu avr5 | FileCheck %s -check-prefix=AVR
+; RUN: llc -O0 < %s -march=avr -mcpu avr51 | FileCheck %s -check-prefix=AVR
+; RUN: llc -O0 < %s -march=avr -mcpu avr6 | FileCheck %s -check-prefix=AVR
+
+define i8 @read8_low_io() {
+; CHECK-LABEL: read8_low_io
+; XMEGA: in r24, 8
+; AVR: lds r24, 8
+  %1 = load i8, i8* inttoptr (i16 8 to i8*)
+  ret i8 %1
+}
+
+define i8 @read8_hi_io() {
+; CHECK-LABEL: read8_hi_io
+; XMEGA: in r24, 40
+; AVR: in r24, 8
+  %1 = load i8, i8* inttoptr (i16 40 to i8*)
+  ret i8 %1
+}
+
+define i8 @read8_maybe_io() {
+; CHECK-LABEL: read8_maybe_io
+; XMEGA: lds r24, 80
+; AVR: in r24, 48
+  %1 = load i8, i8* inttoptr (i16 80 to i8*)
+  ret i8 %1
+}
+
+define i8 @read8_not_io(){
+; CHECK-LABEL: read8_not_io
+; XMEGA: lds r24, 160
+; AVR: lds r24, 160
+  %1 = load i8, i8* inttoptr (i16 160 to i8*)
+  ret i8 %1
+}
