AMDGPU: Remove unnecessary and on conditional branch

The comment explaining why this was necessary is incorrect
in its description of v_cmp's behavior for inactive workitems.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@286134 91177308-0d34-0410-b5e6-96231b3b80d8

diff --git a/lib/Target/AMDGPU/AMDGPUISelDAGToDAG.cpp b/lib/Target/AMDGPU/AMDGPUISelDAGToDAG.cpp
index 2b3b3fd28b4971896812bc2666c92b5072b21eb6..4d55a663d4838c62c33ce76f8d35982edb4b4942 100644 (file)
--- a/lib/Target/AMDGPU/AMDGPUISelDAGToDAG.cpp
+++ b/lib/Target/AMDGPU/AMDGPUISelDAGToDAG.cpp
@@ -1407,26 +1407,12 @@ void AMDGPUDAGToDAGISel::SelectBRCOND(SDNode *N) {
     return;
   }
 
-  // The result of VOPC instructions is or'd against ~EXEC before it is
-  // written to vcc or another SGPR.  This means that the value '1' is always
-  // written to the corresponding bit for results that are masked.  In order
-  // to correctly check against vccz, we need to and VCC with the EXEC
-  // register in order to clear the value from the masked bits.
-
   SDLoc SL(N);
 
-  SDNode *MaskedCond =
-        CurDAG->getMachineNode(AMDGPU::S_AND_B64, SL, MVT::i1,
-                               CurDAG->getRegister(AMDGPU::EXEC, MVT::i1),
-                               Cond);
-  SDValue VCC = CurDAG->getCopyToReg(N->getOperand(0), SL, AMDGPU::VCC,
-                                     SDValue(MaskedCond, 0),
-                                     SDValue()); // Passing SDValue() adds a
-                                                 // glue output.
+  SDValue VCC = CurDAG->getCopyToReg(N->getOperand(0), SL, AMDGPU::VCC, Cond);
   CurDAG->SelectNodeTo(N, AMDGPU::S_CBRANCH_VCCNZ, MVT::Other,
                        N->getOperand(2), // Basic Block
-                       VCC.getValue(0),  // Chain
-                       VCC.getValue(1)); // Glue
+                       VCC.getValue(0));
   return;
 }
 

diff --git a/test/CodeGen/AMDGPU/branch-relaxation.ll b/test/CodeGen/AMDGPU/branch-relaxation.ll
index 5a703f8acfb636bc4ea9d4a15c2f29ec48fcc2d7..c298911504ac3e6eda22562ee07ee0742d02f528 100644 (file)
--- a/test/CodeGen/AMDGPU/branch-relaxation.ll
+++ b/test/CodeGen/AMDGPU/branch-relaxation.ll
@@ -89,10 +89,9 @@ bb3:
 
 ; GCN-LABEL: {{^}}uniform_conditional_min_long_forward_vcnd_branch:
 ; GCN: s_load_dword [[CND:s[0-9]+]]
-; GCN-DAG: v_cmp_eq_f32_e64 [[CMP:s\[[0-9]+:[0-9]+\]]], [[CND]], 0
 ; GCN-DAG: v_mov_b32_e32 [[V_CND:v[0-9]+]], [[CND]]
-; GCN: s_and_b64 vcc, exec, [[CMP]]
-; GCN-NEXT: s_cbranch_vccz [[LONGBB:BB[0-9]+_[0-9]+]]
+; GCN-DAG: v_cmp_eq_f32_e64 vcc, [[CND]], 0
+; GCN: s_cbranch_vccz [[LONGBB:BB[0-9]+_[0-9]+]]
 
 ; GCN-NEXT: [[LONG_JUMP:BB[0-9]+_[0-9]+]]: ; %bb0
 ; GCN-NEXT: s_getpc_b64 vcc
@@ -434,7 +433,7 @@ endif:
 ; GCN: v_nop_e64
 ; GCN: v_nop_e64
 ; GCN: ;;#ASMEND
-; GCN-NEXT: s_and_b64 vcc, exec, -1{{$}}
+; GCN-NEXT: s_mov_b64 vcc, -1{{$}}
 ; GCN-NEXT: s_cbranch_vccz [[RET]]
 
 ; GCN-NEXT: [[LONGBB:BB[0-9]+_[0-9]+]]: ; %loop_body
@@ -478,14 +477,13 @@ ret:
 ; GCN-LABEL: {{^}}long_branch_hang:
 ; GCN: s_cmp_lt_i32 s{{[0-9]+}}, 6
 ; GCN-NEXT: s_cbranch_scc1 [[LONG_BR_0:BB[0-9]+_[0-9]+]]
-
-; GCN: s_add_u32 vcc_lo, vcc_lo, [[LONG_BR_DEST0:BB[0-9]+_[0-9]+]]-(
-; GCN: s_setpc_b64
+; GCN-NEXT: s_branch  [[SHORTB:BB[0-9]+_[0-9]+]]
 
 ; GCN-NEXT: [[LONG_BR_0]]:
+; GCN: s_add_u32 vcc_lo, vcc_lo, [[LONG_BR_DEST0:BB[0-9]+_[0-9]+]]-(
 ; GCN: s_setpc_b64
 
-; GCN-NEXT: [[LONG_BR_DEST0]]:
+; GCN: [[SHORTB]]:
 ; GCN-DAG: v_cmp_lt_i32
 ; GCN-DAG: v_cmp_gt_i32
 ; GCN: s_cbranch_vccnz
@@ -493,6 +491,7 @@ ret:
 ; GCN: s_setpc_b64
 ; GCN: s_setpc_b64
 
+; GCN: [[LONG_BR_DEST0]]
 ; GCN: s_cmp_eq_u32
 ; GCN-NEXT: s_cbranch_scc0
 ; GCN: s_setpc_b64

diff --git a/test/CodeGen/AMDGPU/cf-loop-on-constant.ll b/test/CodeGen/AMDGPU/cf-loop-on-constant.ll
index a68310c608328fb9751099e2ab5af888a51e32b8..b112c49b69e95fbca7a3ce35f531064b434d64f1 100644 (file)
--- a/test/CodeGen/AMDGPU/cf-loop-on-constant.ll
+++ b/test/CodeGen/AMDGPU/cf-loop-on-constant.ll
@@ -97,7 +97,6 @@ for.body:
 ; GCN: v_and_b32_e32 v{{[0-9]+}}, 1, v{{[0-9]+}}
 ; GCN: v_cmp_eq_u32_e32 vcc, 1,
 
-; GCN: s_and_b64 s{{\[[0-9]+:[0-9]+\]}}, exec, vcc
 ; GCN: [[LOOPBB:BB[0-9]+_[0-9]+]]
 ; GCN: s_cbranch_vccnz [[LOOPBB]]
 ; GCN-NEXT: ; BB#2

diff --git a/test/CodeGen/AMDGPU/cgp-bitfield-extract.ll b/test/CodeGen/AMDGPU/cgp-bitfield-extract.ll
index 33daf0292ae1ad5378b4da917f83070210b3c6be..694c67fc5da68759bf4f7c1caca043f7b413d764 100644 (file)
--- a/test/CodeGen/AMDGPU/cgp-bitfield-extract.ll
+++ b/test/CodeGen/AMDGPU/cgp-bitfield-extract.ll
@@ -170,13 +170,12 @@ ret:
 ; OPT: ret
 
 ; GCN-LABEL: {{^}}sink_ubfe_i64_span_midpoint:
+; GCN: s_lshr_b64 s{{\[}}[[LO:[0-9]+]]:{{[0-9]+}}], s{{\[[0-9]+:[0-9]+\]}}, 30
 ; GCN: s_cbranch_vccnz BB3_2
 
-; GCN: s_lshr_b64 s{{\[}}[[LO:[0-9]+]]:{{[0-9]+}}], s{{\[[0-9]+:[0-9]+\]}}, 30
 ; GCN: s_and_b32 s{{[0-9]+}}, s[[LO]], 0xff
 
 ; GCN: BB3_2:
-; GCN: s_lshr_b64 s{{\[}}[[LO:[0-9]+]]:{{[0-9]+}}], s{{\[[0-9]+:[0-9]+\]}}, 30
 ; GCN: s_and_b32 s{{[0-9]+}}, s[[LO]], 0x7f
 
 ; GCN: BB3_3:

diff --git a/test/CodeGen/AMDGPU/i1-copy-implicit-def.ll b/test/CodeGen/AMDGPU/i1-copy-implicit-def.ll
index d6309a2dd5de15efb9d672c9cbc7276dea94a8ba..5a2130006ab9d597c716c69026120ac3258d3cf4 100644 (file)
--- a/test/CodeGen/AMDGPU/i1-copy-implicit-def.ll
+++ b/test/CodeGen/AMDGPU/i1-copy-implicit-def.ll
@@ -1,10 +1,9 @@
-; RUN: llc -march=amdgcn -mcpu=SI -verify-machineinstrs < %s | FileCheck -check-prefix=SI %s
+; RUN: llc -march=amdgcn -verify-machineinstrs < %s | FileCheck -check-prefix=SI %s
 ; RUN: llc -march=amdgcn -mcpu=tonga -verify-machineinstrs < %s | FileCheck -check-prefix=SI %s
 
 ; SILowerI1Copies was not handling IMPLICIT_DEF
 ; SI-LABEL: {{^}}br_implicit_def:
 ; SI: BB#0:
-; SI-NEXT: s_and_b64 vcc, exec
 ; SI-NEXT: s_cbranch_vccnz
 define void @br_implicit_def(i32 addrspace(1)* %out, i32 %arg) #0 {
 bb:

diff --git a/test/CodeGen/AMDGPU/si-annotate-cf-noloop.ll b/test/CodeGen/AMDGPU/si-annotate-cf-noloop.ll
index 1ffb2f839b1275bd50aec39c4378120e93fdf563..c61f2b0744da5273e4faca193ec7089a1ed940ea 100644 (file)
--- a/test/CodeGen/AMDGPU/si-annotate-cf-noloop.ll
+++ b/test/CodeGen/AMDGPU/si-annotate-cf-noloop.ll
@@ -37,7 +37,6 @@ bb5:                                              ; preds = %bb3, %bb1
 ; OPT-NOT: call i1 @llvm.amdgcn.loop
 
 ; GCN-LABEL: {{^}}annotate_ret_noloop:
-; GCN: s_and_b64 vcc
 ; GCN: s_cbranch_vccnz
 ; GCN: s_endpgm
 ; GCN: .Lfunc_end1

diff --git a/test/CodeGen/AMDGPU/skip-if-dead.ll b/test/CodeGen/AMDGPU/skip-if-dead.ll
index 8c8f724e54a38860024ce9ac84cf0f5b16c1b550..3ab0ee15e3dc14420c17611609e9b0a27a9957cd 100644 (file)
--- a/test/CodeGen/AMDGPU/skip-if-dead.ll
+++ b/test/CodeGen/AMDGPU/skip-if-dead.ll
@@ -262,13 +262,11 @@ exit:
 ; CHECK-NEXT: s_endpgm
 
 ; CHECK: [[KILLBB:BB[0-9]+_[0-9]+]]:
-; CHECK: s_and_b64 vcc, exec,
 ; CHECK-NEXT: s_cbranch_vccz [[PHIBB:BB[0-9]+_[0-9]+]]
 
 ; CHECK: [[PHIBB]]:
 ; CHECK: v_cmp_eq_f32_e32 vcc, 0, [[PHIREG]]
-; CHECK: s_and_b64 vcc, exec, vcc
-; CHECK: s_cbranch_vccz [[ENDBB:BB[0-9]+_[0-9]+]]
+; CHECK-NEXT: s_cbranch_vccz [[ENDBB:BB[0-9]+_[0-9]+]]
 
 ; CHECK: ; %bb10
 ; CHECK: v_mov_b32_e32 v{{[0-9]+}}, 9
@@ -303,16 +301,14 @@ end:
 
 ; CHECK-LABEL: {{^}}no_skip_no_successors:
 ; CHECK: v_cmp_nge_f32
-; CHECK: s_and_b64 vcc, exec,
-; CHECK: s_cbranch_vccz [[SKIPKILL:BB[0-9]+_[0-9]+]]
+; CHECK-NEXT: s_cbranch_vccz [[SKIPKILL:BB[0-9]+_[0-9]+]]
 
 ; CHECK: ; %bb6
 ; CHECK: s_mov_b64 exec, 0
 
 ; CHECK: [[SKIPKILL]]:
 ; CHECK: v_cmp_nge_f32
-; CHECK: s_and_b64 vcc, exec, vcc
-; CHECK: s_cbranch_vccz [[UNREACHABLE:BB[0-9]+_[0-9]+]]
+; CHECK-NEXT: s_cbranch_vccz [[UNREACHABLE:BB[0-9]+_[0-9]+]]
 
 ; CHECK: [[UNREACHABLE]]:
 ; CHECK-NEXT: .Lfunc_end{{[0-9]+}}

diff --git a/test/CodeGen/AMDGPU/smrd-vccz-bug.ll b/test/CodeGen/AMDGPU/smrd-vccz-bug.ll
index 966121a48cf43b61b622d5cf46a3cc6234741516..f82ac041969c543033022fc78b25dec868518b79 100644 (file)
--- a/test/CodeGen/AMDGPU/smrd-vccz-bug.ll
+++ b/test/CodeGen/AMDGPU/smrd-vccz-bug.ll
@@ -4,8 +4,7 @@
 
 ; GCN-FUNC: {{^}}vccz_workaround:
 ; GCN: s_load_dword s{{[0-9]+}}, s[{{[0-9]+:[0-9]+}}], 0x0
-; GCN: v_cmp_neq_f32_e64 [[MASK:s\[[0-9]+:[0-9]+\]]], s{{[0-9]+}}, 0{{$}}
-; GCN: s_and_b64 vcc, exec, [[MASK]]
+; GCN: v_cmp_neq_f32_e64 vcc, s{{[0-9]+}}, 0{{$}}
 ; GCN: s_waitcnt lgkmcnt(0)
 ; VCCZ-BUG: s_mov_b64 vcc, vcc
 ; NOVCCZ-BUG-NOT: s_mov_b64 vcc, vcc
@@ -29,7 +28,6 @@ endif:
 
 ; GCN-FUNC: {{^}}vccz_noworkaround:
 ; GCN: v_cmp_neq_f32_e32 vcc, 0, v{{[0-9]+}}
-; GCN: s_and_b64 vcc, exec, vcc
 ; GCN: s_cbranch_vccnz [[EXIT:[0-9A-Za-z_]+]]
 ; GCN: buffer_store_dword
 ; GCN: [[EXIT]]:

diff --git a/test/CodeGen/AMDGPU/uniform-cfg.ll b/test/CodeGen/AMDGPU/uniform-cfg.ll
index a3033b6be87bcefa985ab45dc3da4ea774bc96b0..a462f1488478d40a252202bf21383f5f034902e1 100644 (file)
--- a/test/CodeGen/AMDGPU/uniform-cfg.ll
+++ b/test/CodeGen/AMDGPU/uniform-cfg.ll
@@ -32,7 +32,6 @@ done:
 ; FIXME: We could use _e32 here if we re-used the 0 from [[STORE_VAL]], and
 ; also scheduled the write first.
 ; GCN-DAG: v_cmp_eq_f32_e64 [[COND:vcc|s\[[0-9]+:[0-9]+\]]], s{{[0-9]+}}, 0{{$}}
-; GCN-DAG: s_and_b64 vcc, exec, [[COND]]
 ; GCN-DAG: v_mov_b32_e32 [[STORE_VAL:v[0-9]+]], 0
 ; GCN: s_cbranch_vccnz [[IF_LABEL:[0-9_A-Za-z]+]]
 
@@ -89,7 +88,6 @@ done:
 ; FIXME: We could use _e32 here if we re-used the 0 from [[STORE_VAL]], and
 ; also scheduled the write first.
 ; GCN-DAG: v_cmp_neq_f32_e64 [[COND:vcc|s\[[0-9]+:[0-9]+\]]], s{{[0-9]+}}, 0{{$}}
-; GCN-DAG: s_and_b64 vcc, exec, [[COND]]
 ; GCN-DAG: v_mov_b32_e32 [[STORE_VAL:v[0-9]+]], 0
 ; GCN: s_cbranch_vccnz [[IF_LABEL:[0-9_A-Za-z]+]]
 
@@ -253,8 +251,7 @@ ENDIF:                                            ; preds = %IF, %main_body
 ; GCN: s_load_dword [[COND:s[0-9]+]]
 ; GCN: s_cmp_lt_i32 [[COND]], 1
 ; GCN: s_cbranch_scc1 [[EXIT:[A-Za-z0-9_]+]]
-; GCN: v_cmp_gt_i32_e64 [[MASK:s\[[0-9]+:[0-9]+\]]], [[COND]], 0{{$}}
-; GCN: s_and_b64 vcc, exec, [[MASK]]
+; GCN: v_cmp_gt_i32_e64 vcc, [[COND]], 0{{$}}
 ; GCN: s_cbranch_vccnz [[EXIT]]
 ; GCN: buffer_store
 ; GCN: {{^}}[[EXIT]]:
@@ -439,7 +436,6 @@ bb9:                                              ; preds = %bb8, %bb4
 ; GCN-DAG: v_mov_b32_e32 [[STORE_VAL:v[0-9]+]], 0
 
 ; SI: v_cmp_eq_u64_e64
-; SI: s_and_b64 vcc, exec,
 ; SI: s_cbranch_vccnz [[IF_LABEL:[0-9_A-Za-z]+]]
 
 ; VI: s_cbranch_scc1 [[IF_LABEL:[0-9_A-Za-z]+]]
@@ -471,7 +467,6 @@ done:
 ; GCN-DAG: v_mov_b32_e32 [[STORE_VAL:v[0-9]+]], 0
 
 ; SI: v_cmp_ne_u64_e64
-; SI: s_and_b64 vcc, exec,
 ; SI: s_cbranch_vccnz [[IF_LABEL:[0-9_A-Za-z]+]]
 
 ; VI: s_cbranch_scc1 [[IF_LABEL:[0-9_A-Za-z]+]]
@@ -500,7 +495,6 @@ done:
 
 ; GCN-LABEL: {{^}}uniform_if_scc_i64_sgt:
 ; GCN: v_cmp_gt_i64_e64
-; GCN: s_and_b64 vcc, exec,
 ; GCN: s_cbranch_vccnz [[IF_LABEL:[0-9_A-Za-z]+]]
 
 ; Fall-through to the else

diff --git a/test/CodeGen/AMDGPU/wqm.ll b/test/CodeGen/AMDGPU/wqm.ll
index 14c279b3b957cdd51cd18bc18fd2d4d5e3ecad23..4def7357efe287e9a32fa6d1046f4f702c7d58b1 100644 (file)
--- a/test/CodeGen/AMDGPU/wqm.ll
+++ b/test/CodeGen/AMDGPU/wqm.ll
@@ -355,12 +355,11 @@ main_body:
 ; CHECK: s_wqm_b64 exec, exec
 ; CHECK-DAG: v_mov_b32_e32 [[CTR:v[0-9]+]], 0
 ; CHECK-DAG: v_mov_b32_e32 [[SEVEN:v[0-9]+]], 0x40e00000
-; CHECK: s_branch [[LOOPHDR:BB[0-9]+_[0-9]+]]
 
+; CHECK: [[LOOPHDR:BB[0-9]+_[0-9]+]]: ; %body
 ; CHECK: v_add_f32_e32 [[CTR]], 2.0, [[CTR]]
-; CHECK: [[LOOPHDR]]: ; %loop
 ; CHECK: v_cmp_lt_f32_e32 vcc, [[SEVEN]], [[CTR]]
-; CHECK: s_cbranch_vccz
+; CHECK: s_cbranch_vccz [[LOOPHDR]]
 ; CHECK: ; %break
 
 ; CHECK: ; return