From: Tim Northover <tnorthover@apple.com>
Date: Wed, 19 Jul 2017 22:08:08 +0000 (+0000)
Subject: GlobalISel: fix SUBREG_TO_REG implementation.
X-Git-Url: https://granicus.if.org/sourcecode?a=commitdiff_plain;h=e81b44f152a897f07df39cc1259fa1aea4944181;p=llvm

GlobalISel: fix SUBREG_TO_REG implementation.

The first argument needs to be an immediate rather than a register. Should fix
some crashes in the verifier bot.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@308540 91177308-0d34-0410-b5e6-96231b3b80d8
---

diff --git a/lib/Target/AArch64/AArch64InstructionSelector.cpp b/lib/Target/AArch64/AArch64InstructionSelector.cpp
index 0c9c1b35440..148e973bb1c 100644
--- a/lib/Target/AArch64/AArch64InstructionSelector.cpp
+++ b/lib/Target/AArch64/AArch64InstructionSelector.cpp
@@ -780,6 +780,29 @@ bool AArch64InstructionSelector::select(MachineInstr &I) const {
 
     return constrainSelectedInstRegOperands(I, TII, TRI, RBI);
   }
+  case TargetOpcode::G_UNMERGE_VALUES: {
+    // 
+    LLT SrcTy = MRI.getType(I.getOperand(1).getReg());
+    // Larger extracts are vectors, same-size extracts should be something else
+    // by now (either split up or simplified to a COPY).
+    if (SrcTy.getSizeInBits() > 64 || Ty.getSizeInBits() > 32)
+      return false;
+
+    I.setDesc(TII.get(AArch64::UBFMXri));
+    MachineInstrBuilder(MF, I).addImm(I.getOperand(2).getImm() +
+                                      Ty.getSizeInBits() - 1);
+
+    unsigned DstReg = MRI.createGenericVirtualRegister(LLT::scalar(64));
+    BuildMI(MBB, std::next(I.getIterator()), I.getDebugLoc(),
+            TII.get(AArch64::COPY))
+        .addDef(I.getOperand(0).getReg())
+        .addUse(DstReg, 0, AArch64::sub_32);
+    RBI.constrainGenericRegister(I.getOperand(0).getReg(),
+                                 AArch64::GPR32RegClass, MRI);
+    I.getOperand(0).setReg(DstReg);
+
+    return constrainSelectedInstRegOperands(I, TII, TRI, RBI);
+  }
 
   case TargetOpcode::G_INSERT: {
     LLT SrcTy = MRI.getType(I.getOperand(2).getReg());
@@ -798,7 +821,7 @@ bool AArch64InstructionSelector::select(MachineInstr &I) const {
     BuildMI(MBB, I.getIterator(), I.getDebugLoc(),
             TII.get(AArch64::SUBREG_TO_REG))
         .addDef(SrcReg)
-        .addUse(0)
+        .addImm(0)
         .addUse(I.getOperand(2).getReg())
         .addImm(AArch64::sub_32);
     RBI.constrainGenericRegister(I.getOperand(2).getReg(),
diff --git a/test/CodeGen/AArch64/GlobalISel/select-insert-extract.mir b/test/CodeGen/AArch64/GlobalISel/select-insert-extract.mir
index 8248a63732c..e88e151bd24 100644
--- a/test/CodeGen/AArch64/GlobalISel/select-insert-extract.mir
+++ b/test/CodeGen/AArch64/GlobalISel/select-insert-extract.mir
@@ -15,11 +15,11 @@ body:             |
     %1:gpr(s64) = G_IMPLICIT_DEF
 
     ; CHECK:  body:
-    ; CHECK: [[TMP:%[0-9]+]] = SUBREG_TO_REG _, %0, 15
+    ; CHECK: [[TMP:%[0-9]+]] = SUBREG_TO_REG 0, %0, 15
     ; CHECK: %2 = BFMXri %1, [[TMP]], 0, 31
     %2:gpr(s64) = G_INSERT %1, %0, 0
 
-    ; CHECK: [[TMP:%[0-9]+]] = SUBREG_TO_REG _, %0, 15
+    ; CHECK: [[TMP:%[0-9]+]] = SUBREG_TO_REG 0, %0, 15
     ; CHECK: %3 = BFMXri %1, [[TMP]], 51, 31
     %3:gpr(s64) = G_INSERT %1, %0, 13