Files
clang-p2996/llvm/test/CodeGen/AMDGPU/loop_break.ll
Matt Arsenault d3406bc45c StructurizeCFG: Directly invert cmp instructions
The most common case for a branch condition is
a single use compare. Directly invert the branch
predicate rather than adding a lot of xor i1 true
which the DAG will have to fold later.

This produces nicer to read structurizer output.

This produces some random changes in codegen
due to the DAG swapping branch conditions itself,
and then does a poor job of dealing with those
inverts.

llvm-svn: 300732
2017-04-19 18:29:07 +00:00

330 lines
11 KiB
LLVM

; RUN: opt -mtriple=amdgcn-- -S -structurizecfg -si-annotate-control-flow %s | FileCheck -check-prefix=OPT %s
; RUN: llc -march=amdgcn -verify-machineinstrs < %s | FileCheck -check-prefix=GCN %s
; Uses llvm.amdgcn.break
; OPT-LABEL: @break_loop(
; OPT: bb1:
; OPT: call i64 @llvm.amdgcn.break(i64
; OPT-NEXT: br i1 %cmp0, label %bb4, label %Flow
; OPT: bb4:
; OPT: load volatile
; OPT: %cmp1 = icmp sge i32 %tmp, %load
; OPT: call i64 @llvm.amdgcn.if.break(
; OPT: br label %Flow
; OPT: Flow:
; OPT: call i1 @llvm.amdgcn.loop(i64
; OPT: br i1 %{{[0-9]+}}, label %bb9, label %bb1
; OPT: bb9:
; OPT: call void @llvm.amdgcn.end.cf(i64
; TODO: Can remove exec fixes in return block
; GCN-LABEL: {{^}}break_loop:
; GCN: s_mov_b64 [[INITMASK:s\[[0-9]+:[0-9]+\]]], 0{{$}}
; GCN: [[LOOP_ENTRY:BB[0-9]+_[0-9]+]]: ; %bb1
; GCN: s_or_b64 [[MASK:s\[[0-9]+:[0-9]+\]]], exec, [[INITMASK]]
; GCN: v_cmp_lt_i32_e32 vcc, -1
; GCN: s_and_b64 vcc, exec, vcc
; GCN-NEXT: s_cbranch_vccnz [[FLOW:BB[0-9]+_[0-9]+]]
; GCN: ; BB#2: ; %bb4
; GCN: buffer_load_dword
; GCN: v_cmp_ge_i32_e32 vcc,
; GCN: s_or_b64 [[MASK]], vcc, [[INITMASK]]
; GCN: [[FLOW]]:
; GCN: s_mov_b64 [[INITMASK]], [[MASK]]
; GCN: s_andn2_b64 exec, exec, [[MASK]]
; GCN-NEXT: s_cbranch_execnz [[LOOP_ENTRY]]
; GCN: ; BB#4: ; %bb9
; GCN-NEXT: s_or_b64 exec, exec, [[MASK]]
; GCN-NEXT: s_endpgm
define amdgpu_kernel void @break_loop(i32 %arg) #0 {
bb:
%id = call i32 @llvm.amdgcn.workitem.id.x()
%tmp = sub i32 %id, %arg
br label %bb1
bb1:
%lsr.iv = phi i32 [ undef, %bb ], [ %lsr.iv.next, %bb4 ]
%lsr.iv.next = add i32 %lsr.iv, 1
%cmp0 = icmp slt i32 %lsr.iv.next, 0
br i1 %cmp0, label %bb4, label %bb9
bb4:
%load = load volatile i32, i32 addrspace(1)* undef, align 4
%cmp1 = icmp slt i32 %tmp, %load
br i1 %cmp1, label %bb1, label %bb9
bb9:
ret void
}
; OPT-LABEL: @undef_phi_cond_break_loop(
; OPT: bb1:
; OPT-NEXT: %phi.broken = phi i64 [ %loop.phi, %Flow ], [ 0, %bb ]
; OPT-NEXT: %lsr.iv = phi i32 [ undef, %bb ], [ %tmp2, %Flow ]
; OPT: %0 = call i64 @llvm.amdgcn.if.break(i1 undef, i64 %phi.broken)
; OPT-NEXT: br i1 %cmp0, label %bb4, label %Flow
; OPT: bb4:
; OPT-NEXT: %load = load volatile i32, i32 addrspace(1)* undef, align 4
; OPT-NEXT: %cmp1 = icmp sge i32 %tmp, %load
; OPT-NEXT: %1 = call i64 @llvm.amdgcn.if.break(i1 %cmp1, i64 %phi.broken)
; OPT-NEXT: br label %Flow
; OPT: Flow:
; OPT-NEXT: %loop.phi = phi i64 [ %1, %bb4 ], [ %0, %bb1 ]
; OPT-NEXT: %tmp2 = phi i32 [ %lsr.iv.next, %bb4 ], [ undef, %bb1 ]
; OPT-NEXT: %2 = call i1 @llvm.amdgcn.loop(i64 %loop.phi)
; OPT-NEXT: br i1 %2, label %bb9, label %bb1
; OPT: bb9: ; preds = %Flow
; OPT-NEXT: call void @llvm.amdgcn.end.cf(i64 %loop.phi)
; OPT-NEXT: store volatile i32 7
; OPT-NEXT: ret void
define amdgpu_kernel void @undef_phi_cond_break_loop(i32 %arg) #0 {
bb:
%id = call i32 @llvm.amdgcn.workitem.id.x()
%tmp = sub i32 %id, %arg
br label %bb1
bb1: ; preds = %Flow, %bb
%lsr.iv = phi i32 [ undef, %bb ], [ %tmp2, %Flow ]
%lsr.iv.next = add i32 %lsr.iv, 1
%cmp0 = icmp slt i32 %lsr.iv.next, 0
br i1 %cmp0, label %bb4, label %Flow
bb4: ; preds = %bb1
%load = load volatile i32, i32 addrspace(1)* undef, align 4
%cmp1 = icmp sge i32 %tmp, %load
br label %Flow
Flow: ; preds = %bb4, %bb1
%tmp2 = phi i32 [ %lsr.iv.next, %bb4 ], [ undef, %bb1 ]
%tmp3 = phi i1 [ %cmp1, %bb4 ], [ undef, %bb1 ]
br i1 %tmp3, label %bb9, label %bb1
bb9: ; preds = %Flow
store volatile i32 7, i32 addrspace(3)* undef
ret void
}
; FIXME: ConstantExpr compare of address to null folds away
@lds = addrspace(3) global i32 undef
; OPT-LABEL: @constexpr_phi_cond_break_loop(
; OPT: bb1:
; OPT-NEXT: %phi.broken = phi i64 [ %loop.phi, %Flow ], [ 0, %bb ]
; OPT-NEXT: %lsr.iv = phi i32 [ undef, %bb ], [ %tmp2, %Flow ]
; OPT: %0 = call i64 @llvm.amdgcn.if.break(i1 icmp ne (i32 addrspace(3)* inttoptr (i32 4 to i32 addrspace(3)*), i32 addrspace(3)* @lds), i64 %phi.broken)
; OPT-NEXT: br i1 %cmp0, label %bb4, label %Flow
; OPT: bb4:
; OPT-NEXT: %load = load volatile i32, i32 addrspace(1)* undef, align 4
; OPT-NEXT: %cmp1 = icmp sge i32 %tmp, %load
; OPT-NEXT: %1 = call i64 @llvm.amdgcn.if.break(i1 %cmp1, i64 %phi.broken)
; OPT-NEXT: br label %Flow
; OPT: Flow:
; OPT-NEXT: %loop.phi = phi i64 [ %1, %bb4 ], [ %0, %bb1 ]
; OPT-NEXT: %tmp2 = phi i32 [ %lsr.iv.next, %bb4 ], [ undef, %bb1 ]
; OPT-NEXT: %2 = call i1 @llvm.amdgcn.loop(i64 %loop.phi)
; OPT-NEXT: br i1 %2, label %bb9, label %bb1
; OPT: bb9: ; preds = %Flow
; OPT-NEXT: call void @llvm.amdgcn.end.cf(i64 %loop.phi)
; OPT-NEXT: store volatile i32 7
; OPT-NEXT: ret void
define amdgpu_kernel void @constexpr_phi_cond_break_loop(i32 %arg) #0 {
bb:
%id = call i32 @llvm.amdgcn.workitem.id.x()
%tmp = sub i32 %id, %arg
br label %bb1
bb1: ; preds = %Flow, %bb
%lsr.iv = phi i32 [ undef, %bb ], [ %tmp2, %Flow ]
%lsr.iv.next = add i32 %lsr.iv, 1
%cmp0 = icmp slt i32 %lsr.iv.next, 0
br i1 %cmp0, label %bb4, label %Flow
bb4: ; preds = %bb1
%load = load volatile i32, i32 addrspace(1)* undef, align 4
%cmp1 = icmp sge i32 %tmp, %load
br label %Flow
Flow: ; preds = %bb4, %bb1
%tmp2 = phi i32 [ %lsr.iv.next, %bb4 ], [ undef, %bb1 ]
%tmp3 = phi i1 [ %cmp1, %bb4 ], [ icmp ne (i32 addrspace(3)* inttoptr (i32 4 to i32 addrspace(3)*), i32 addrspace(3)* @lds), %bb1 ]
br i1 %tmp3, label %bb9, label %bb1
bb9: ; preds = %Flow
store volatile i32 7, i32 addrspace(3)* undef
ret void
}
; OPT-LABEL: @true_phi_cond_break_loop(
; OPT: bb1:
; OPT-NEXT: %phi.broken = phi i64 [ %loop.phi, %Flow ], [ 0, %bb ]
; OPT-NEXT: %lsr.iv = phi i32 [ undef, %bb ], [ %tmp2, %Flow ]
; OPT: %0 = call i64 @llvm.amdgcn.break(i64 %phi.broken)
; OPT: br i1 %cmp0, label %bb4, label %Flow
; OPT: bb4:
; OPT-NEXT: %load = load volatile i32, i32 addrspace(1)* undef, align 4
; OPT-NEXT: %cmp1 = icmp sge i32 %tmp, %load
; OPT-NEXT: %1 = call i64 @llvm.amdgcn.if.break(i1 %cmp1, i64 %phi.broken)
; OPT-NEXT: br label %Flow
; OPT: Flow:
; OPT-NEXT: %loop.phi = phi i64 [ %1, %bb4 ], [ %0, %bb1 ]
; OPT-NEXT: %tmp2 = phi i32 [ %lsr.iv.next, %bb4 ], [ undef, %bb1 ]
; OPT-NEXT: %2 = call i1 @llvm.amdgcn.loop(i64 %loop.phi)
; OPT-NEXT: br i1 %2, label %bb9, label %bb1
; OPT: bb9: ; preds = %Flow
; OPT-NEXT: call void @llvm.amdgcn.end.cf(i64 %loop.phi)
; OPT-NEXT: store volatile i32 7
; OPT-NEXT: ret void
define amdgpu_kernel void @true_phi_cond_break_loop(i32 %arg) #0 {
bb:
%id = call i32 @llvm.amdgcn.workitem.id.x()
%tmp = sub i32 %id, %arg
br label %bb1
bb1: ; preds = %Flow, %bb
%lsr.iv = phi i32 [ undef, %bb ], [ %tmp2, %Flow ]
%lsr.iv.next = add i32 %lsr.iv, 1
%cmp0 = icmp slt i32 %lsr.iv.next, 0
br i1 %cmp0, label %bb4, label %Flow
bb4: ; preds = %bb1
%load = load volatile i32, i32 addrspace(1)* undef, align 4
%cmp1 = icmp sge i32 %tmp, %load
br label %Flow
Flow: ; preds = %bb4, %bb1
%tmp2 = phi i32 [ %lsr.iv.next, %bb4 ], [ undef, %bb1 ]
%tmp3 = phi i1 [ %cmp1, %bb4 ], [ true, %bb1 ]
br i1 %tmp3, label %bb9, label %bb1
bb9: ; preds = %Flow
store volatile i32 7, i32 addrspace(3)* undef
ret void
}
; OPT-LABEL: @false_phi_cond_break_loop(
; OPT: bb1:
; OPT-NEXT: %phi.broken = phi i64 [ %loop.phi, %Flow ], [ 0, %bb ]
; OPT-NEXT: %lsr.iv = phi i32 [ undef, %bb ], [ %tmp2, %Flow ]
; OPT-NOT: call
; OPT: br i1 %cmp0, label %bb4, label %Flow
; OPT: bb4:
; OPT-NEXT: %load = load volatile i32, i32 addrspace(1)* undef, align 4
; OPT-NEXT: %cmp1 = icmp sge i32 %tmp, %load
; OPT-NEXT: %0 = call i64 @llvm.amdgcn.if.break(i1 %cmp1, i64 %phi.broken)
; OPT-NEXT: br label %Flow
; OPT: Flow:
; OPT-NEXT: %loop.phi = phi i64 [ %0, %bb4 ], [ %phi.broken, %bb1 ]
; OPT-NEXT: %tmp2 = phi i32 [ %lsr.iv.next, %bb4 ], [ undef, %bb1 ]
; OPT-NEXT: %1 = call i1 @llvm.amdgcn.loop(i64 %loop.phi)
; OPT-NEXT: br i1 %1, label %bb9, label %bb1
; OPT: bb9: ; preds = %Flow
; OPT-NEXT: call void @llvm.amdgcn.end.cf(i64 %loop.phi)
; OPT-NEXT: store volatile i32 7
; OPT-NEXT: ret void
define amdgpu_kernel void @false_phi_cond_break_loop(i32 %arg) #0 {
bb:
%id = call i32 @llvm.amdgcn.workitem.id.x()
%tmp = sub i32 %id, %arg
br label %bb1
bb1: ; preds = %Flow, %bb
%lsr.iv = phi i32 [ undef, %bb ], [ %tmp2, %Flow ]
%lsr.iv.next = add i32 %lsr.iv, 1
%cmp0 = icmp slt i32 %lsr.iv.next, 0
br i1 %cmp0, label %bb4, label %Flow
bb4: ; preds = %bb1
%load = load volatile i32, i32 addrspace(1)* undef, align 4
%cmp1 = icmp sge i32 %tmp, %load
br label %Flow
Flow: ; preds = %bb4, %bb1
%tmp2 = phi i32 [ %lsr.iv.next, %bb4 ], [ undef, %bb1 ]
%tmp3 = phi i1 [ %cmp1, %bb4 ], [ false, %bb1 ]
br i1 %tmp3, label %bb9, label %bb1
bb9: ; preds = %Flow
store volatile i32 7, i32 addrspace(3)* undef
ret void
}
; Swap order of branches in flow block so that the true phi is
; continue.
; OPT-LABEL: @invert_true_phi_cond_break_loop(
; OPT: bb1:
; OPT-NEXT: %phi.broken = phi i64 [ %1, %Flow ], [ 0, %bb ]
; OPT-NEXT: %lsr.iv = phi i32 [ undef, %bb ], [ %tmp2, %Flow ]
; OPT-NEXT: %lsr.iv.next = add i32 %lsr.iv, 1
; OPT-NEXT: %cmp0 = icmp slt i32 %lsr.iv.next, 0
; OPT-NEXT: br i1 %cmp0, label %bb4, label %Flow
; OPT: bb4:
; OPT-NEXT: %load = load volatile i32, i32 addrspace(1)* undef, align 4
; OPT-NEXT: %cmp1 = icmp sge i32 %tmp, %load
; OPT-NEXT: br label %Flow
; OPT: Flow:
; OPT-NEXT: %tmp2 = phi i32 [ %lsr.iv.next, %bb4 ], [ undef, %bb1 ]
; OPT-NEXT: %tmp3 = phi i1 [ %cmp1, %bb4 ], [ true, %bb1 ]
; OPT-NEXT: %0 = xor i1 %tmp3, true
; OPT-NEXT: %1 = call i64 @llvm.amdgcn.if.break(i1 %0, i64 %phi.broken)
; OPT-NEXT: %2 = call i1 @llvm.amdgcn.loop(i64 %1)
; OPT-NEXT: br i1 %2, label %bb9, label %bb1
; OPT: bb9:
; OPT-NEXT: call void @llvm.amdgcn.end.cf(i64 %1)
; OPT-NEXT: store volatile i32 7, i32 addrspace(3)* undef
; OPT-NEXT: ret void
define amdgpu_kernel void @invert_true_phi_cond_break_loop(i32 %arg) #0 {
bb:
%id = call i32 @llvm.amdgcn.workitem.id.x()
%tmp = sub i32 %id, %arg
br label %bb1
bb1: ; preds = %Flow, %bb
%lsr.iv = phi i32 [ undef, %bb ], [ %tmp2, %Flow ]
%lsr.iv.next = add i32 %lsr.iv, 1
%cmp0 = icmp slt i32 %lsr.iv.next, 0
br i1 %cmp0, label %bb4, label %Flow
bb4: ; preds = %bb1
%load = load volatile i32, i32 addrspace(1)* undef, align 4
%cmp1 = icmp sge i32 %tmp, %load
br label %Flow
Flow: ; preds = %bb4, %bb1
%tmp2 = phi i32 [ %lsr.iv.next, %bb4 ], [ undef, %bb1 ]
%tmp3 = phi i1 [ %cmp1, %bb4 ], [ true, %bb1 ]
br i1 %tmp3, label %bb1, label %bb9
bb9: ; preds = %Flow
store volatile i32 7, i32 addrspace(3)* undef
ret void
}
declare i32 @llvm.amdgcn.workitem.id.x() #1
attributes #0 = { nounwind }
attributes #1 = { nounwind readnone }