[MachineVerifier] Add check that tied physregs aren't different.

Summary: Added MachineVerifier code to check register ties more thoroughly, especially so that physical registers that are tied are the same. This may help e.g. when creating MIR files.

Original patch by Jesper Antonsson

Reviewers: stoklund, sanjoy, qcolombet

Reviewed By: qcolombet

Subscribers: qcolombet, llvm-commits

Differential Revision: https://reviews.llvm.org/D34394

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@307259 91177308-0d34-0410-b5e6-96231b3b80d8

diff --git a/lib/CodeGen/MachineVerifier.cpp b/lib/CodeGen/MachineVerifier.cpp
index e65c256c1bb5a7e441edf078b5d9788dd82807b9..fcb544806dda029a67ab05e3b72bf3175521897d 100644 (file)
--- a/lib/CodeGen/MachineVerifier.cpp
+++ b/lib/CodeGen/MachineVerifier.cpp
@@ -985,6 +985,14 @@ MachineVerifier::visitMachineOperand(const MachineOperand *MO, unsigned MONum) {
         report("Operand should be tied", MO, MONum);
       else if (unsigned(TiedTo) != MI->findTiedOperandIdx(MONum))
         report("Tied def doesn't match MCInstrDesc", MO, MONum);
+      else if (TargetRegisterInfo::isPhysicalRegister(MO->getReg())) {
+        const MachineOperand &MOTied = MI->getOperand(TiedTo);
+        if (!MOTied.isReg())
+          report("Tied counterpart must be a register", &MOTied, TiedTo);
+        else if (TargetRegisterInfo::isPhysicalRegister(MOTied.getReg()) &&
+                 MO->getReg() != MOTied.getReg())
+          report("Tied physical registers must match.", &MOTied, TiedTo);
+      }
     } else if (MO->isReg() && MO->isTied())
       report("Explicit operand should not be tied", MO, MONum);
   } else {

diff --git a/test/CodeGen/MIR/X86/tied-physical-regs-match.mir b/test/CodeGen/MIR/X86/tied-physical-regs-match.mir
new file mode 100644 (file)
index 0000000..1ddf649
--- /dev/null
+++ b/test/CodeGen/MIR/X86/tied-physical-regs-match.mir
@@ -0,0 +1,22 @@
+# RUN: not llc -march=x86-64 -run-pass none -o /dev/null %s 2>&1 | FileCheck %s
+# This test ensures that the Machine Verifier detects tied physical registers
+# that doesn't match.
+
+--- |
+
+  define i32 @foo() {
+  entry:
+    ret i32 0
+  }
+
+...
+---
+name:            foo
+body: |
+  bb.0.entry:
+    liveins: %rdi
+
+    ; CHECK: Tied physical registers must match.
+    %rbx = AND64rm killed %rdx, killed %rdi, 1, _, 0, _, implicit-def dead %eflags
+    RETQ %rbx
+...