[RISCV] Support multiple memory operands in expandRV32ZdinxStore.

TailMerge can create stores with multiple memory operands. We
need to split all of them instead of assuming there is only one.

Author: topperc

llvm/lib/Target/RISCV/RISCVExpandPseudoInsts.cpp

@@ -341,15 +341,15 @@ bool RISCVExpandPseudo::expandRV32ZdinxStore(MachineBasicBlock &MBB,
                 .addImm(MBBI->getOperand(2).getImm() + 4);
   }
 
-  if (!MBBI->memoperands_empty()) {
-    assert(MBBI->hasOneMemOperand() && "Expected mem operand");
-    MachineMemOperand *OldMMO = MBBI->memoperands().front();
-    MachineFunction *MF = MBB.getParent();
-    MachineMemOperand *MMOLo = MF->getMachineMemOperand(OldMMO, 0, 4);
-    MachineMemOperand *MMOHi = MF->getMachineMemOperand(OldMMO, 4, 4);
-    MIBLo.setMemRefs(MMOLo);
-    MIBHi.setMemRefs(MMOHi);
+  MachineFunction *MF = MBB.getParent();
+  SmallVector<MachineMemOperand *> NewLoMMOs;
+  SmallVector<MachineMemOperand *> NewHiMMOs;
+  for (const MachineMemOperand *MMO : MBBI->memoperands()) {
+    NewLoMMOs.push_back(MF->getMachineMemOperand(MMO, 0, 4));
+    NewHiMMOs.push_back(MF->getMachineMemOperand(MMO, 4, 4));
   }
+  MIBLo.setMemRefs(NewLoMMOs);
+  MIBHi.setMemRefs(NewHiMMOs);
 
   MBBI->eraseFromParent();
   return true;
@@ -401,15 +401,15 @@ bool RISCVExpandPseudo::expandRV32ZdinxLoad(MachineBasicBlock &MBB,
                 .add(MBBI->getOperand(2));
   }
 
-  if (!MBBI->memoperands_empty()) {
-    assert(MBBI->hasOneMemOperand() && "Expected mem operand");
-    MachineMemOperand *OldMMO = MBBI->memoperands().front();
-    MachineFunction *MF = MBB.getParent();
-    MachineMemOperand *MMOLo = MF->getMachineMemOperand(OldMMO, 0, 4);
-    MachineMemOperand *MMOHi = MF->getMachineMemOperand(OldMMO, 4, 4);
-    MIBLo.setMemRefs(MMOLo);
-    MIBHi.setMemRefs(MMOHi);
+  MachineFunction *MF = MBB.getParent();
+  SmallVector<MachineMemOperand *> NewLoMMOs;
+  SmallVector<MachineMemOperand *> NewHiMMOs;
+  for (const MachineMemOperand *MMO : MBBI->memoperands()) {
+    NewLoMMOs.push_back(MF->getMachineMemOperand(MMO, 0, 4));
+    NewHiMMOs.push_back(MF->getMachineMemOperand(MMO, 4, 4));
   }
+  MIBLo.setMemRefs(NewLoMMOs);
+  MIBHi.setMemRefs(NewHiMMOs);
 
   MBBI->eraseFromParent();
   return true;

llvm/test/CodeGen/RISCV/zdinx-memoperand.ll

@@ -0,0 +1,37 @@
+; NOTE: Assertions have been autogenerated by utils/update_llc_test_checks.py UTC_ARGS: --version 5
+; RUN: llc < %s -mtriple=riscv32 -mattr=+zdinx | FileCheck %s
+
+; This test previously asserted because TailMerge created a PseudoRV32ZdinxSD
+; with 2 memoperands which RISCVExpandPseudo could not handle.
+
+define i32 @foo(double %x, ptr %y, i64 %0, i64 %1, i1 %cmp6.not, ptr %arrayidx13, ptr %arrayidx20) {
+; CHECK-LABEL: foo:
+; CHECK:       # %bb.0: # %entry
+; CHECK-NEXT:    andi a0, a7, 1
+; CHECK-NEXT:    beqz a0, .LBB0_2
+; CHECK-NEXT:  # %bb.1: # %if.else
+; CHECK-NEXT:    lw a0, 4(sp)
+; CHECK-NEXT:    j .LBB0_3
+; CHECK-NEXT:  .LBB0_2: # %if.then7
+; CHECK-NEXT:    lw a0, 0(sp)
+; CHECK-NEXT:  .LBB0_3: # %common.ret
+; CHECK-NEXT:    fcvt.d.w a2, zero
+; CHECK-NEXT:    sw a2, 0(a0)
+; CHECK-NEXT:    sw a3, 4(a0)
+; CHECK-NEXT:    li a0, 0
+; CHECK-NEXT:    ret
+entry:
+  br i1 %cmp6.not, label %if.else, label %if.then7
+
+common.ret:                                       ; preds = %if.else, %if.then7
+  ret i32 0
+
+if.then7:                                         ; preds = %entry
+  store double 0.000000e+00, ptr %arrayidx13, align 8
+  br label %common.ret
+
+if.else:                                          ; preds = %entry
+  store double 0.000000e+00, ptr %arrayidx20, align 8
+  br label %common.ret
+}
+