AMDGPU: Fix violating constant bus restriction

You can't use madmk/madmk if it already uses an SGPR input.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@313298 91177308-0d34-0410-b5e6-96231b3b80d8

diff --git a/lib/Target/AMDGPU/SIInstrInfo.cpp b/lib/Target/AMDGPU/SIInstrInfo.cpp
index e60124e75a95aa46ffa03630a9bed1684583a351..de0eb8b7427c729d9bede7c358764bc70ff253ab 100644 (file)
--- a/lib/Target/AMDGPU/SIInstrInfo.cpp
+++ b/lib/Target/AMDGPU/SIInstrInfo.cpp
@@ -2150,9 +2150,8 @@ static int64_t getFoldableImm(const MachineOperand* MO) {
   const MachineFunction *MF = MO->getParent()->getParent()->getParent();
   const MachineRegisterInfo &MRI = MF->getRegInfo();
   auto Def = MRI.getUniqueVRegDef(MO->getReg());
-  if (Def && (Def->getOpcode() == AMDGPU::S_MOV_B32 ||
-              Def->getOpcode() == AMDGPU::V_MOV_B32_e32) &&
-     Def->getOperand(1).isImm())
+  if (Def && Def->getOpcode() == AMDGPU::V_MOV_B32_e32 &&
+      Def->getOperand(1).isImm())
     return Def->getOperand(1).getImm();
   return AMDGPU::NoRegister;
 }
@@ -2194,7 +2193,9 @@ MachineInstr *SIInstrInfo::convertToThreeAddress(MachineFunction::iterator &MBB,
   const MachineOperand *Clamp = getNamedOperand(MI, AMDGPU::OpName::clamp);
   const MachineOperand *Omod = getNamedOperand(MI, AMDGPU::OpName::omod);
 
-  if (!Src0Mods && !Src1Mods && !Clamp && !Omod) {
+  if (!Src0Mods && !Src1Mods && !Clamp && !Omod &&
+      // If we have an SGPR input, we will violate the constant bus restriction.
+      !RI.isSGPRReg(MBB->getParent()->getRegInfo(), Src0->getReg())) {
     if (auto Imm = getFoldableImm(Src2)) {
       return BuildMI(*MBB, MI, MI.getDebugLoc(),
                      get(IsF16 ? AMDGPU::V_MADAK_F16 : AMDGPU::V_MADAK_F32))

diff --git a/test/CodeGen/AMDGPU/twoaddr-mad.mir b/test/CodeGen/AMDGPU/twoaddr-mad.mir
index ebda1d26ddc203bed439355593c07e7150a7e7d2..cd8931fb21ae82211114b5e27a006a0e5aae1afd 100644 (file)
--- a/test/CodeGen/AMDGPU/twoaddr-mad.mir
+++ b/test/CodeGen/AMDGPU/twoaddr-mad.mir
@@ -108,3 +108,25 @@ body:             |
     %1 = V_MOV_B32_e32 1078523331, implicit %exec
     %2 = V_MAC_F16_e32 killed %0.sub0, %0.sub1, %1, implicit %exec
 ...
+
+# Make sure constant bus restriction isn't violated if src0 is an SGPR.
+
+# GCN-LABEL: name: test_madak_sgpr_src0_f32
+# GCN: %1 = V_MOV_B32_e32 1078523331, implicit %exec
+# GCN: %2 = V_MAD_F32 0, killed %0, 0, %1, 0, %3, 0, 0, implicit %exec
+
+---
+name:            test_madak_sgpr_src0_f32
+registers:
+  - { id: 0, class: sreg_32_xm0 }
+  - { id: 1, class: vgpr_32}
+  - { id: 2, class: vgpr_32 }
+  - { id: 3, class: vgpr_32 }
+body:             |
+  bb.0:
+
+    %0 = IMPLICIT_DEF
+    %1 = V_MOV_B32_e32 1078523331, implicit %exec
+    %2 = V_MAC_F32_e32 killed %0, %1, %3, implicit %exec
+
+...