[AMDGPU][NFC] Cleanly make 32-bit abs legal (llvm#164837)

Cleanly make 32-bit abs legal only in SIISelLowering.cpp

Signed-off-by: John Lu <[email protected]>

Author: LU-JOHN

llvm/lib/Target/AMDGPU/AMDGPUISelLowering.cpp

@@ -514,8 +514,8 @@ AMDGPUTargetLowering::AMDGPUTargetLowering(const TargetMachine &TM,
       MVT::i64, Custom);
   setOperationAction(ISD::SELECT_CC, MVT::i64, Expand);
 
-  setOperationAction({ISD::ABS, ISD::SMIN, ISD::UMIN, ISD::SMAX, ISD::UMAX},
-                     MVT::i32, Legal);
+  setOperationAction({ISD::SMIN, ISD::UMIN, ISD::SMAX, ISD::UMAX}, MVT::i32,
+                     Legal);
 
   setOperationAction(
       {ISD::CTTZ, ISD::CTTZ_ZERO_UNDEF, ISD::CTLZ, ISD::CTLZ_ZERO_UNDEF},

llvm/lib/Target/AMDGPU/R600ISelLowering.cpp

@@ -45,9 +45,6 @@ R600TargetLowering::R600TargetLowering(const TargetMachine &TM,
   // Legalize loads and stores to the private address space.
   setOperationAction(ISD::LOAD, {MVT::i32, MVT::v2i32, MVT::v4i32}, Custom);
 
-  // 32-bit ABS is legal for AMDGPU except for R600
-  setOperationAction(ISD::ABS, MVT::i32, Expand);
-
   // EXTLOAD should be the same as ZEXTLOAD. It is legal for some address
   // spaces, so it is custom lowered to handle those where it isn't.
   for (auto Op : {ISD::SEXTLOAD, ISD::ZEXTLOAD, ISD::EXTLOAD})

llvm/lib/Target/AMDGPU/SIISelLowering.cpp

@@ -298,7 +298,7 @@ SITargetLowering::SITargetLowering(const TargetMachine &TM,
   setOperationAction(ISD::BR_CC,
                      {MVT::i1, MVT::i32, MVT::i64, MVT::f32, MVT::f64}, Expand);
 
-  setOperationAction({ISD::UADDO, ISD::USUBO}, MVT::i32, Legal);
+  setOperationAction({ISD::ABS, ISD::UADDO, ISD::USUBO}, MVT::i32, Legal);
 
   setOperationAction({ISD::UADDO_CARRY, ISD::USUBO_CARRY}, MVT::i32, Legal);