[MachineCopyPropagation] Extend pass to do COPY source forwarding

Summary:
This change extends MachineCopyPropagation to do COPY source forwarding
and adds an additional run of the pass to the default pass pipeline just
after register allocation.

This version of this patch uses the newly added
MachineOperand::isRenamable bit to avoid forwarding registers is such a
way as to violate constraints that aren't captured in the
Machine IR (e.g. ABI or ISA constraints).

This change is a continuation of the work started in D30751.

Reviewers: qcolombet, javed.absar, MatzeB, jonpa, tstellar

Subscribers: tpr, mgorny, mcrosier, nhaehnle, nemanjai, jyknight, hfinkel, arsenm, inouehrs, eraman, sdardis, guyblank, fedor.sergeev, aheejin, dschuff, jfb, myatsina, llvm-commits

Differential Revision: https://reviews.llvm.org/D41835

llvm-svn: 323991

4 files changed, 16 insertions, 16 deletions

diff --git a/llvm/test/CodeGen/AMDGPU/callee-special-input-sgprs.ll b/llvm/test/CodeGen/AMDGPU/callee-special-input-sgprs.ll
index 8082a095a08..343ba691af5 100644
--- a/llvm/test/CodeGen/AMDGPU/callee-special-input-sgprs.ll
+++ b/llvm/test/CodeGen/AMDGPU/callee-special-input-sgprs.ll
@@ -547,16 +547,16 @@ define void @func_use_every_sgpr_input_call_use_workgroup_id_xyz() #1 {
 ; GCN: s_mov_b32 s5, s32
 ; GCN: s_add_u32 s32, s32, 0x300
 
-; GCN-DAG: s_mov_b32 [[SAVE_X:s[0-9]+]], s14
-; GCN-DAG: s_mov_b32 [[SAVE_Y:s[0-9]+]], s15
-; GCN-DAG: s_mov_b32 [[SAVE_Z:s[0-9]+]], s16
+; GCN-DAG: s_mov_b32 [[SAVE_X:s[0-57-9][0-9]*]], s14
+; GCN-DAG: s_mov_b32 [[SAVE_Y:s[0-68-9][0-9]*]], s15
+; GCN-DAG: s_mov_b32 [[SAVE_Z:s[0-79][0-9]*]], s16
 ; GCN-DAG: s_mov_b64 {{s\[[0-9]+:[0-9]+\]}}, s[6:7]
 ; GCN-DAG: s_mov_b64 {{s\[[0-9]+:[0-9]+\]}}, s[8:9]
 ; GCN-DAG: s_mov_b64 {{s\[[0-9]+:[0-9]+\]}}, s[10:11]
 
-; GCN-DAG: s_mov_b32 s6, [[SAVE_X]]
-; GCN-DAG: s_mov_b32 s7, [[SAVE_Y]]
-; GCN-DAG: s_mov_b32 s8, [[SAVE_Z]]
+; GCN-DAG: s_mov_b32 s6, s14
+; GCN-DAG: s_mov_b32 s7, s15
+; GCN-DAG: s_mov_b32 s8, s16
 ; GCN: s_swappc_b64
 
 ; GCN: buffer_store_dword v{{[0-9]+}}, off, s[0:3], s5 offset:4
diff --git a/llvm/test/CodeGen/AMDGPU/fix-vgpr-copies.mir b/llvm/test/CodeGen/AMDGPU/fix-vgpr-copies.mir
index c53ff28b547..66a238dff82 100644
--- a/llvm/test/CodeGen/AMDGPU/fix-vgpr-copies.mir
+++ b/llvm/test/CodeGen/AMDGPU/fix-vgpr-copies.mir
@@ -1,4 +1,4 @@
-# RUN: llc -march=amdgcn -start-after=greedy -stop-after=si-optimize-exec-masking -o - %s | FileCheck %s
+# RUN: llc -march=amdgcn -start-after=greedy -disable-copyprop -stop-after=si-optimize-exec-masking -o - %s | FileCheck %s
 # Check that we first do all vector instructions and only then change exec
 # CHECK-DAG:  COPY $vgpr10_vgpr11
 # CHECK-DAG:  COPY $vgpr12_vgpr13
diff --git a/llvm/test/CodeGen/AMDGPU/multilevel-break.ll b/llvm/test/CodeGen/AMDGPU/multilevel-break.ll
index 8cc02d49709..5917f87e19a 100644
--- a/llvm/test/CodeGen/AMDGPU/multilevel-break.ll
+++ b/llvm/test/CodeGen/AMDGPU/multilevel-break.ll
@@ -78,7 +78,7 @@ ENDIF:                                            ; preds = %LOOP
 
 ; Uses a copy intsead of an or
 ; GCN: s_mov_b64 [[COPY:s\[[0-9]+:[0-9]+\]]], [[BREAK_REG]]
-; GCN: s_or_b64 [[BREAK_REG]], exec, [[COPY]]
+; GCN: s_or_b64 [[BREAK_REG]], exec, [[BREAK_REG]]
 define amdgpu_kernel void @multi_if_break_loop(i32 %arg) #0 {
 bb:
   %id = call i32 @llvm.amdgcn.workitem.id.x()
diff --git a/llvm/test/CodeGen/AMDGPU/ret.ll b/llvm/test/CodeGen/AMDGPU/ret.ll
index 831c71dff79..2d673a9b0cd 100644
--- a/llvm/test/CodeGen/AMDGPU/ret.ll
+++ b/llvm/test/CodeGen/AMDGPU/ret.ll
@@ -2,10 +2,10 @@
 ; RUN: llc -march=amdgcn -mcpu=tonga -verify-machineinstrs < %s | FileCheck -check-prefix=GCN %s
 
 ; GCN-LABEL: {{^}}vgpr:
-; GCN: v_mov_b32_e32 v1, v0
-; GCN-DAG: v_add_f32_e32 v0, 1.0, v1
-; GCN-DAG: exp mrt0 v1, v1, v1, v1 done vm
+; GCN-DAG: v_mov_b32_e32 v1, v0
+; GCN-DAG: exp mrt0 v0, v0, v0, v0 done vm
 ; GCN: s_waitcnt expcnt(0)
+; GCN: v_add_f32_e32 v0, 1.0, v0
 ; GCN-NOT: s_endpgm
 define amdgpu_vs { float, float } @vgpr([9 x <16 x i8>] addrspace(2)* byval %arg, i32 inreg %arg1, i32 inreg %arg2, float %arg3) #0 {
 bb:
@@ -204,13 +204,13 @@ bb:
 }
 
 ; GCN-LABEL: {{^}}both:
-; GCN: v_mov_b32_e32 v1, v0
-; GCN-DAG: exp mrt0 v1, v1, v1, v1 done vm
-; GCN-DAG: v_add_f32_e32 v0, 1.0, v1
-; GCN-DAG: s_add_i32 s0, s3, 2
+; GCN-DAG: exp mrt0 v0, v0, v0, v0 done vm
+; GCN-DAG: v_mov_b32_e32 v1, v0
 ; GCN-DAG: s_mov_b32 s1, s2
-; GCN: s_mov_b32 s2, s3
 ; GCN: s_waitcnt expcnt(0)
+; GCN: v_add_f32_e32 v0, 1.0, v0
+; GCN-DAG: s_add_i32 s0, s3, 2
+; GCN-DAG: s_mov_b32 s2, s3
 ; GCN-NOT: s_endpgm
 define amdgpu_vs { float, i32, float, i32, i32 } @both([9 x <16 x i8>] addrspace(2)* byval %arg, i32 inreg %arg1, i32 inreg %arg2, float %arg3) #0 {
 bb: