AMDGPU/GCN: Exit early in hazard recognizer if there is no vreg argument

wbinvl.* are vector instruction that do not sue vector registers.

v2: check only M?BUF instructions

Differential Revision: https://reviews.llvm.org/D26633

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@287056 91177308-0d34-0410-b5e6-96231b3b80d8

lib/Target/AMDGPU/GCNHazardRecognizer.cpp

@@ -400,6 +400,10 @@ int GCNHazardRecognizer::createsVALUHazard(const MachineInstr &MI) {
     VDataRCID = Desc.OpInfo[VDataIdx].RegClass;
 
   if (TII->isMUBUF(MI) || TII->isMTBUF(MI)) {
+    // There is no hazard if the instruction does not use vector regs
+    // (like wbinvl1)
+    if (VDataIdx == -1)
+      return -1;
     // For MUBUF/MTBUF instructions this hazard only exists if the
     // instruction is not using a register in the soffset field.
     const MachineOperand *SOffset =

test/CodeGen/AMDGPU/llvm.amdgcn.buffer.wbinvl1.vol.ll

@@ -7,9 +7,11 @@ declare void @llvm.amdgcn.buffer.wbinvl1.vol() #0
 ; GCN-NEXT: ; BB#0:
 ; CI-NEXT: buffer_wbinvl1_vol ; encoding: [0x00,0x00,0xc0,0xe1,0x00,0x00,0x00,0x00]
 ; VI-NEXT: buffer_wbinvl1_vol ; encoding: [0x00,0x00,0xfc,0xe0,0x00,0x00,0x00,0x00]
-; GCN-NEXT: s_endpgm
+; GCN: s_endpgm
 define void @test_buffer_wbinvl1_vol() #0 {
   call void @llvm.amdgcn.buffer.wbinvl1.vol()
+; This used to crash in hazard recognizer
+  store i8 0, i8 addrspace(1)* undef, align 1
   ret void
 }