[AVR] Fix incorrect register state for LDRdPtr

[Jim]

Summary

LDRdPtr expanded from LDWRdPtr shouldn't define its second operand(SrcReg).
The second operand is its source register.
Add -verify-machineinstrs into command line of testcases can trigger this error.

[Jim]

Add -verify-machineinstrs for brind.ll

[dylanmckay]

Solid fix, once the lint errors are fixed I will approve.

[dylanmckay]

Actually I'll just approve under condition that the pre-merge clang-format checks are fixed before commit.

[Jim]

Format code.

llvm/lib/Target/AVR/AVRExpandPseudoInsts.cpp

bool AVRExpandPseudo::expand<AVR::LDWRdPtr>(Block &MBB, BlockIt MBBI) {
   if (DstReg == SrcReg)
     TmpReg = scavengeGPR8(MI);
 
   unsigned CurDstLoReg = (DstReg == SrcReg) ? TmpReg : DstLoReg;
   unsigned CurDstHiReg = (DstReg == SrcReg) ? TmpReg : DstHiReg;
 
   // Load low byte.
   auto MIBLO = buildMI(MBB, MBBI, OpLo)
                    .addReg(CurDstLoReg, RegState::Define)
-    .addReg(SrcReg, RegState::Define);
+                   .addReg(SrcReg);
 
   // Push low byte onto stack if necessary.
   if (TmpReg)
     buildMI(MBB, MBBI, AVR::PUSHRr).addReg(TmpReg);
 
   // Load high byte.
   auto MIBHI = buildMI(MBB, MBBI, OpHi)
     .addReg(CurDstHiReg, RegState::Define)

llvm/test/CodeGen/AVR/PR37143.ll

-; RUN: llc -mattr=avr6,sram < %s -march=avr | FileCheck %s
+; RUN: llc -mattr=avr6,sram < %s -march=avr -verify-machineinstrs | FileCheck %s
 
 ; CHECK: ld {{r[0-9]+}}, [[PTR:[XYZ]]]
 ; CHECK: ldd {{r[0-9]+}}, [[PTR]]+1
 ; CHECK: st [[PTR2:[XYZ]]], {{r[0-9]+}}
 ; CHECK: std [[PTR2]]+1, {{r[0-9]+}}
 define void @load_store_16(i16* nocapture %ptr) local_unnamed_addr #1 {
 entry:
   %0 = load i16, i16* %ptr, align 2
   %add = add i16 %0, 5
   store i16 %add, i16* %ptr, align 2
   ret void
 }

llvm/test/CodeGen/AVR/brind.ll

-; RUN: llc -mattr=sram,eijmpcall < %s -march=avr | FileCheck %s
+; RUN: llc -mattr=sram,eijmpcall < %s -march=avr -verify-machineinstrs | FileCheck %s
 
 @brind.k = private unnamed_addr constant [2 x i8*] [i8* blockaddress(@brind, %return), i8* blockaddress(@brind, %b)], align 1
 
 define i8 @brind(i8 %p) {
 ; CHECK-LABEL: brind:
 ; CHECK: ijmp
 entry:
   %idxprom = sext i8 %p to i16

llvm/test/CodeGen/AVR/load.ll

-; RUN: llc -mattr=avr6,sram < %s -march=avr | FileCheck %s
+; RUN: llc -mattr=avr6,sram < %s -march=avr -verify-machineinstrs | FileCheck %s
 
 define i8 @load8(i8* %x) {
 ; CHECK-LABEL: load8:
 ; CHECK: ld r24, {{[XYZ]}}
   %1 = load i8, i8* %x
   ret i8 %1
 }
 

llvm/test/CodeGen/AVR/pseudo/LDWRdPtr.mir

 
 ---
 name:            test_ldwrdptr
 body: |
   bb.0.entry:
 
     ; CHECK-LABEL: test_ldwrdptr
 
-    ; CHECK:      $r0, $r31r30 = LDRdPtr
+    ; CHECK:               $r0 = LDRdPtr $r31r30
     ; CHECK-NEXT:          $r1 = LDDRdPtrQ $r31r30, 1
 
     $r1r0 = LDWRdPtr $r31r30
 ...