[AMDGPU] Implement isSDNodeAlwaysUniform for INTRINSIC_W_CHAIN

[jayfoad]

There are no always uniform side-effecting intrinsics upstream to test
this with, but we have examples downstream.

[llvmbot]

@llvm/pr-subscribers-backend-amdgpu

Author: Jay Foad (jayfoad)

Changes

There are no always uniform side-effecting intrinsics upstream to test
this with, but we have examples downstream.

---

Full diff: https://github.com/llvm/llvm-project/pull/110114.diff

1 Files Affected:

• (modified) llvm/lib/Target/AMDGPU/AMDGPUISelLowering.cpp (+4)

diff --git a/llvm/lib/Target/AMDGPU/AMDGPUISelLowering.cpp b/llvm/lib/Target/AMDGPU/AMDGPUISelLowering.cpp
index fad51ce8285e01..94fdf4effa10a1 100644
--- a/llvm/lib/Target/AMDGPU/AMDGPUISelLowering.cpp
+++ b/llvm/lib/Target/AMDGPU/AMDGPUISelLowering.cpp
@@ -900,6 +900,10 @@ bool AMDGPUTargetLowering::isSDNodeAlwaysUniform(const SDNode *N) const {
     unsigned IntrID = N->getConstantOperandVal(0);
     return AMDGPU::isIntrinsicAlwaysUniform(IntrID);
   }
+  case ISD::INTRINSIC_W_CHAIN: {
+    unsigned IntrID = N->getConstantOperandVal(1);
+    return AMDGPU::isIntrinsicAlwaysUniform(IntrID);
+  }
   case ISD::LOAD:
     if (cast<LoadSDNode>(N)->getMemOperand()->getAddrSpace() ==
         AMDGPUAS::CONSTANT_ADDRESS_32BIT)