LiveRegMatrix: Fix some subreg interference checks

Surprisingly, one of the three interference checks in LiveRegMatrix was
using the main live range instead of the apropriate subregister range
resulting in unnecessarily conservative results.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@296722 91177308-0d34-0410-b5e6-96231b3b80d8

diff --git a/include/llvm/CodeGen/LiveRegMatrix.h b/include/llvm/CodeGen/LiveRegMatrix.h
index 7373e79..fa6827f 100644 (file)
--- a/include/llvm/CodeGen/LiveRegMatrix.h
+++ b/include/llvm/CodeGen/LiveRegMatrix.h
@@ -141,7 +141,7 @@ public:
   /// Use MCRegUnitIterator to enumerate all regunits in the desired PhysReg.
   /// This returns a reference to an internal Query data structure that is only
   /// valid until the next query() call.
-  LiveIntervalUnion::Query &query(LiveInterval &VirtReg, unsigned RegUnit);
+  LiveIntervalUnion::Query &query(const LiveRange &LR, unsigned RegUnit);
 
   /// Directly access the live interval unions per regunit.
   /// This returns an array indexed by the regunit number.

diff --git a/lib/CodeGen/LiveRegMatrix.cpp b/lib/CodeGen/LiveRegMatrix.cpp
index 596d787..882de1a 100644 (file)
--- a/lib/CodeGen/LiveRegMatrix.cpp
+++ b/lib/CodeGen/LiveRegMatrix.cpp
@@ -175,10 +175,10 @@ bool LiveRegMatrix::checkRegUnitInterference(LiveInterval &VirtReg,
   return Result;
 }
 
-LiveIntervalUnion::Query &LiveRegMatrix::query(LiveInterval &VirtReg,
+LiveIntervalUnion::Query &LiveRegMatrix::query(const LiveRange &LR,
                                                unsigned RegUnit) {
   LiveIntervalUnion::Query &Q = Queries[RegUnit];
-  Q.init(UserTag, VirtReg, Matrix[RegUnit]);
+  Q.init(UserTag, LR, Matrix[RegUnit]);
   return Q;
 }
 
@@ -196,9 +196,12 @@ LiveRegMatrix::checkInterference(LiveInterval &VirtReg, unsigned PhysReg) {
     return IK_RegUnit;
 
   // Check the matrix for virtual register interference.
-  for (MCRegUnitIterator Units(PhysReg, TRI); Units.isValid(); ++Units)
-    if (query(VirtReg, *Units).checkInterference())
-      return IK_VirtReg;
+  bool Interference = foreachUnit(TRI, VirtReg, PhysReg,
+                                  [&](unsigned Unit, const LiveRange &LR) {
+    return query(LR, Unit).checkInterference();
+  });
+  if (Interference)
+    return IK_VirtReg;
 
   return IK_Free;
 }

diff --git a/test/CodeGen/AMDGPU/add.v2i16.ll b/test/CodeGen/AMDGPU/add.v2i16.ll
index 7431f14..db3c88a 100644 (file)
--- a/test/CodeGen/AMDGPU/add.v2i16.ll
+++ b/test/CodeGen/AMDGPU/add.v2i16.ll
@@ -191,10 +191,10 @@ define void @v_test_add_v2i16_zext_to_v2i32(<2 x i32> addrspace(1)* %out, <2 x i
 ; GFX9: flat_load_dword [[A:v[0-9]+]]
 ; GFX9: flat_load_dword [[B:v[0-9]+]]
 
+; GFX9: v_mov_b32_e32 v{{[0-9]+}}, 0{{$}}
 ; GFX9: v_pk_add_u16 [[ADD:v[0-9]+]], [[A]], [[B]]
 ; GFX9-DAG: v_and_b32_e32 v[[ELT0:[0-9]+]], 0xffff, [[ADD]]
 ; GFX9-DAG: v_lshrrev_b32_e32 v[[ELT1:[0-9]+]], 16, [[ADD]]
-; GFX9-DAG: v_mov_b32_e32 v{{[0-9]+}}, 0{{$}}
 ; GFX9: buffer_store_dwordx4
 
 ; VI: flat_load_ushort v[[A_LO:[0-9]+]]
@@ -203,9 +203,9 @@ define void @v_test_add_v2i16_zext_to_v2i32(<2 x i32> addrspace(1)* %out, <2 x i
 ; VI: flat_load_ushort v[[B_HI:[0-9]+]]
 
 ; VI: v_mov_b32_e32 v{{[0-9]+}}, 0{{$}}
+; VI: v_mov_b32_e32 v{{[0-9]+}}, 0{{$}}
 ; VI: v_add_u16_e32
 ; VI: v_add_u16_e32
-; VI: v_mov_b32_e32 v{{[0-9]+}}, 0{{$}}
 
 ; VI: buffer_store_dwordx4
 define void @v_test_add_v2i16_zext_to_v2i64(<2 x i64> addrspace(1)* %out, <2 x i16> addrspace(1)* %in0, <2 x i16> addrspace(1)* %in1) #1 {

diff --git a/test/CodeGen/AMDGPU/br_cc.f16.ll b/test/CodeGen/AMDGPU/br_cc.f16.ll
index 4ae15e8..3fe6f87 100644 (file)
--- a/test/CodeGen/AMDGPU/br_cc.f16.ll
+++ b/test/CodeGen/AMDGPU/br_cc.f16.ll
@@ -5,20 +5,19 @@
 ; GCN: buffer_load_ushort v[[A_F16:[0-9]+]]
 ; GCN: buffer_load_ushort v[[B_F16:[0-9]+]]
 
-; SI:  v_cvt_f32_f16_e32 v[[A_F32:[0-9]+]], v[[A_F16]]
-; SI:  v_cvt_f32_f16_e32 v[[B_F32:[0-9]+]], v[[B_F16]]
-; SI:  v_cmp_nlt_f32_e32 vcc, v[[A_F32]], v[[B_F32]]
+; SI-DAG:  v_cvt_f32_f16_e32 v[[A_F32:[0-9]+]], v[[A_F16]]
+; SI-DAG:  v_cvt_f32_f16_e32 v[[B_F32:[0-9]+]], v[[B_F16]]
+; SI:  v_cmp_nlt_f32_e32 vcc, v[[B_F32]], v[[A_F32]]
 ; VI:  v_cmp_nlt_f16_e32 vcc, v[[A_F16]], v[[B_F16]]
 ; GCN: s_cbranch_vccnz
 
 ; GCN: one{{$}}
-; SI: v_cvt_f16_f32_e32 v[[A_F16:[0-9]+]], v[[A_F32]]
-; SI: s_branch
-; VI: buffer_store_short
-; VI: s_endpgm
+; SI: v_cvt_f16_f32_e32 v[[A_F16:[0-9]+]], v[[B_F32]]
+; GCN: buffer_store_short
+; GCN: s_endpgm
 
 ; GCN: two{{$}}
-; SI:  v_cvt_f16_f32_e32 v[[B_F16:[0-9]+]], v[[B_F32]]
+; SI:  v_cvt_f16_f32_e32 v[[B_F16:[0-9]+]], v[[A_F32]]
 ; GCN: buffer_store_short v[[B_F16]]
 ; GCN: s_endpgm
 define void @br_cc_f16(

diff --git a/test/CodeGen/AMDGPU/fneg-combines.ll b/test/CodeGen/AMDGPU/fneg-combines.ll
index 41f31de..acd4f7e 100644 (file)
--- a/test/CodeGen/AMDGPU/fneg-combines.ll
+++ b/test/CodeGen/AMDGPU/fneg-combines.ll
@@ -1195,9 +1195,8 @@ define void @v_fneg_fp_round_fneg_f64_to_f32(float addrspace(1)* %out, double ad
 ; GCN: {{buffer|flat}}_load_dwordx2 v{{\[}}[[A_LO:[0-9]+]]:[[A_HI:[0-9]+]]{{\]}}
 ; GCN-DAG: v_cvt_f32_f64_e32 [[RESULT:v[0-9]+]], v{{\[}}[[A_LO]]:[[A_HI]]{{\]}}
 ; GCN-DAG: v_xor_b32_e32 v[[NEG_A_HI:[0-9]+]], 0x80000000, v[[A_HI]]
-; GCN-DAG: v_mov_b32_e32 v[[NEG_A_LO:[0-9]+]], v[[A_LO]]
 ; GCN: buffer_store_dword [[RESULT]]
-; GCN: buffer_store_dwordx2 v{{\[}}[[NEG_A_LO]]:[[NEG_A_HI]]{{\]}}
+; GCN: buffer_store_dwordx2 v{{\[}}[[A_LO]]:[[NEG_A_HI]]{{\]}}
 define void @v_fneg_fp_round_store_use_fneg_f64_to_f32(float addrspace(1)* %out, double addrspace(1)* %a.ptr) #0 {
   %tid = call i32 @llvm.amdgcn.workitem.id.x()
   %tid.ext = sext i32 %tid to i64

diff --git a/test/CodeGen/AMDGPU/insert_vector_elt.v2i16.ll b/test/CodeGen/AMDGPU/insert_vector_elt.v2i16.ll
index 079a441..e4e634d 100644 (file)
--- a/test/CodeGen/AMDGPU/insert_vector_elt.v2i16.ll
+++ b/test/CodeGen/AMDGPU/insert_vector_elt.v2i16.ll
@@ -417,10 +417,10 @@ define void @v_insertelement_v2i16_dynamic_sgpr(<2 x i16> addrspace(1)* %out, <2
 
 ; GFX89-DAG: s_mov_b32 [[MASKK:s[0-9]+]], 0xffff{{$}}
 ; GFX89-DAG: v_lshlrev_b32_e32 [[SCALED_IDX:v[0-9]+]], 16, [[IDX]]
-; GFX89: v_lshlrev_b32_e64 [[MASK:v[0-9]+]], [[SCALED_IDX]], [[MASKK]]
+; GFX89-DAG: v_lshlrev_b32_e64 [[MASK:v[0-9]+]], [[SCALED_IDX]], [[MASKK]]
 
-; CI: v_lshlrev_b32_e32 [[SCALED_IDX:v[0-9]+]], 16, [[IDX]]
-; CI: v_lshl_b32_e32 [[MASK:v[0-9]+]], 0xffff, [[SCALED_IDX]]
+; CI-DAG: v_lshlrev_b32_e32 [[SCALED_IDX:v[0-9]+]], 16, [[IDX]]
+; CI-DAG: v_lshl_b32_e32 [[MASK:v[0-9]+]], 0xffff, [[SCALED_IDX]]
 
 ; GCN: v_bfi_b32 [[RESULT:v[0-9]+]], [[MASK]], [[K]], [[VEC]]
 ; GCN: flat_store_dword v{{\[[0-9]+:[0-9]+\]}}, [[RESULT]]
@@ -444,10 +444,10 @@ define void @v_insertelement_v2i16_dynamic_vgpr(<2 x i16> addrspace(1)* %out, <2
 
 ; GFX89-DAG: s_mov_b32 [[MASKK:s[0-9]+]], 0xffff{{$}}
 ; GFX89-DAG: v_lshlrev_b32_e32 [[SCALED_IDX:v[0-9]+]], 16, [[IDX]]
-; GFX89: v_lshlrev_b32_e64 [[MASK:v[0-9]+]], [[SCALED_IDX]], [[MASKK]]
+; GFX89-DAG: v_lshlrev_b32_e64 [[MASK:v[0-9]+]], [[SCALED_IDX]], [[MASKK]]
 
-; CI: v_lshlrev_b32_e32 [[SCALED_IDX:v[0-9]+]], 16, [[IDX]]
-; CI: v_lshl_b32_e32 [[MASK:v[0-9]+]], 0xffff, [[SCALED_IDX]]
+; CI-DAG: v_lshlrev_b32_e32 [[SCALED_IDX:v[0-9]+]], 16, [[IDX]]
+; CI-DAG: v_lshl_b32_e32 [[MASK:v[0-9]+]], 0xffff, [[SCALED_IDX]]
 
 ; GCN: v_bfi_b32 [[RESULT:v[0-9]+]], [[MASK]], [[K]], [[VEC]]
 ; GCN: flat_store_dword v{{\[[0-9]+:[0-9]+\]}}, [[RESULT]]

diff --git a/test/CodeGen/AMDGPU/sub.v2i16.ll b/test/CodeGen/AMDGPU/sub.v2i16.ll
index 96686cf..b282b51 100644 (file)
--- a/test/CodeGen/AMDGPU/sub.v2i16.ll
+++ b/test/CodeGen/AMDGPU/sub.v2i16.ll
@@ -188,10 +188,10 @@ define void @v_test_sub_v2i16_zext_to_v2i32(<2 x i32> addrspace(1)* %out, <2 x i
 ; GFX9: flat_load_dword [[A:v[0-9]+]]
 ; GFX9: flat_load_dword [[B:v[0-9]+]]
 
+; GFX9: v_mov_b32_e32 v{{[0-9]+}}, 0{{$}}
 ; GFX9: v_pk_sub_i16 [[ADD:v[0-9]+]], [[A]], [[B]]
 ; GFX9-DAG: v_and_b32_e32 v[[ELT0:[0-9]+]], 0xffff, [[ADD]]
 ; GFX9-DAG: v_lshrrev_b32_e32 v[[ELT1:[0-9]+]], 16, [[ADD]]
-; GFX9-DAG: v_mov_b32_e32 v{{[0-9]+}}, 0{{$}}
 ; GFX9: buffer_store_dwordx4
 
 ; VI: flat_load_ushort v[[A_LO:[0-9]+]]
@@ -199,10 +199,10 @@ define void @v_test_sub_v2i16_zext_to_v2i32(<2 x i32> addrspace(1)* %out, <2 x i
 ; VI: flat_load_ushort v[[B_LO:[0-9]+]]
 ; VI: flat_load_ushort v[[B_HI:[0-9]+]]
 
-; VI: v_mov_b32_e32 v{{[0-9]+}}, 0{{$}}
-; VI: v_subrev_u16_e32
-; VI: v_subrev_u16_e32
-; VI: v_mov_b32_e32 v{{[0-9]+}}, 0{{$}}
+; VI-DAG: v_mov_b32_e32 v{{[0-9]+}}, 0{{$}}
+; VI-DAG: v_mov_b32_e32 v{{[0-9]+}}, 0{{$}}
+; VI-DAG: v_subrev_u16_e32
+; VI-DAG: v_subrev_u16_e32
 
 ; VI: buffer_store_dwordx4
 define void @v_test_sub_v2i16_zext_to_v2i64(<2 x i64> addrspace(1)* %out, <2 x i16> addrspace(1)* %in0, <2 x i16> addrspace(1)* %in1) #1 {

diff --git a/test/CodeGen/AMDGPU/subreg_interference.mir b/test/CodeGen/AMDGPU/subreg_interference.mir
new file mode 100644 (file)
index 0000000..24d06a5
--- /dev/null
+++ b/test/CodeGen/AMDGPU/subreg_interference.mir
@@ -0,0 +1,24 @@
+# RUN: llc -o - %s -mtriple=amdgcn--amdhsa -verify-machineinstrs -run-pass=greedy,virtregrewriter | FileCheck %s
+---
+# We should not detect any interference between v0/v1 here and only allocate
+# sgpr0-sgpr3.
+#
+# CHECK-LABEL: func0
+# CHECK: S_NOP 0, implicit-def %sgpr0
+# CHECK: S_NOP 0, implicit-def %sgpr3
+# CHECK: S_NOP 0, implicit-def %sgpr1
+# CHECK: S_NOP 0, implicit-def %sgpr2
+# CHECK: S_NOP 0, implicit %sgpr0, implicit %sgpr3
+# CHECK: S_NOP 0, implicit %sgpr1, implicit %sgpr2
+name: func0
+body: |
+  bb.0:
+    S_NOP 0, implicit-def undef %0.sub0 : sreg_128
+    S_NOP 0, implicit-def %0.sub3
+    S_NOP 0, implicit-def undef %1.sub1 : sreg_128
+    S_NOP 0, implicit-def %1.sub2
+
+
+    S_NOP 0, implicit %0.sub0, implicit %0.sub3
+    S_NOP 0, implicit %1.sub1, implicit %1.sub2
+...