CodeGen: Add a hook for getFenceOperandTy

Currently the operand type for ATOMIC_FENCE assumes value type of a pointer in address space 0.
This is fine for most targets. However for amdgcn target, the size of pointer in address space 0
depends on triple environment. For amdgiz environment, it is 64 bit but for other environment it is
32 bit. On the other hand, amdgcn target expects 32 bit fence operands independent of the target
triple environment. Therefore a hook is need in target lowering for getting the fence operand type.

This patch has no effect on targets other than amdgcn.

Differential Revision: https://reviews.llvm.org/D32186

llvm-svn: 301215

2 files changed, 10 insertions, 0 deletions

diff --git a/llvm/lib/Target/AMDGPU/AMDGPUISelLowering.h b/llvm/lib/Target/AMDGPU/AMDGPUISelLowering.h
index 948a4ac76a0..13cbfe26793 100644
--- a/llvm/lib/Target/AMDGPU/AMDGPUISelLowering.h
+++ b/llvm/lib/Target/AMDGPU/AMDGPUISelLowering.h
@@ -231,6 +231,10 @@ public:
   AMDGPUAS getAMDGPUAS() const {
     return AMDGPUASI;
   }
+
+  MVT getFenceOperandTy(const DataLayout &DL) const override {
+    return MVT::i32;
+  }
 };
 
 namespace AMDGPUISD {
diff --git a/llvm/lib/Target/AMDGPU/SIInstructions.td b/llvm/lib/Target/AMDGPU/SIInstructions.td
index c6828ecd9c2..89c815c5262 100644
--- a/llvm/lib/Target/AMDGPU/SIInstructions.td
+++ b/llvm/lib/Target/AMDGPU/SIInstructions.td
@@ -94,6 +94,12 @@ defm V_INTERP_MOV_F32 : VINTRP_m <
 //===----------------------------------------------------------------------===//
 // Pseudo Instructions
 //===----------------------------------------------------------------------===//
+def ATOMIC_FENCE : SPseudoInstSI<
+  (outs), (ins i32imm:$ordering, i32imm:$scope),
+  [(atomic_fence (i32 imm:$ordering), (i32 imm:$scope))],
+  "ATOMIC_FENCE $ordering, $scope"> {
+  let hasSideEffects = 1;
+}
 
 let hasSideEffects = 0, mayLoad = 0, mayStore = 0, Uses = [EXEC] in {