llvm-project/llvm/test/Analysis/ScalarEvolution/guards.ll

142 lines
4.0 KiB
LLVM

; RUN: opt -S -indvars < %s | FileCheck %s
; Check that SCEV is able to recognize and use guards to prove
; conditions gaurding loop entries and backedges. This isn't intended
; to be a comprehensive test of SCEV's simplification capabilities,
; tests directly testing e.g. if SCEV can elide a sext should go
; elsewhere.
target datalayout = "n8:16:32:64"
declare void @llvm.experimental.guard(i1, ...)
define void @test_1(i1* %cond_buf, i32* %len_buf) {
; CHECK-LABEL: @test_1(
entry:
%len = load i32, i32* %len_buf, !range !{i32 1, i32 2147483648}
br label %loop
loop:
; CHECK: loop:
; CHECK: call void (i1, ...) @llvm.experimental.guard(i1 true) [ "deopt"() ]
; CHECK: %iv.inc.cmp = icmp slt i32 %iv.inc, %len
; CHECK: call void (i1, ...) @llvm.experimental.guard(i1 %iv.inc.cmp) [ "deopt"() ]
; CHECK: leave:
%iv = phi i32 [ 0, %entry ], [ %iv.inc, %loop ]
%iv.inc = add i32 %iv, 1
%iv.cmp = icmp slt i32 %iv, %len
call void(i1, ...) @llvm.experimental.guard(i1 %iv.cmp) [ "deopt"() ]
%iv.inc.cmp = icmp slt i32 %iv.inc, %len
call void(i1, ...) @llvm.experimental.guard(i1 %iv.inc.cmp) [ "deopt"() ]
%becond = load volatile i1, i1* %cond_buf
br i1 %becond, label %loop, label %leave
leave:
ret void
}
define void @test_2(i32 %n, i32* %len_buf) {
; CHECK-LABEL: @test_2(
; CHECK: [[LEN_SEXT:%[^ ]+]] = sext i32 %len to i64
; CHECK: br label %loop
entry:
%len = load i32, i32* %len_buf, !range !{i32 0, i32 2147483648}
br label %loop
loop:
; CHECK: loop:
; CHECK: %indvars.iv = phi i64 [ %indvars.iv.next, %loop ], [ 0, %entry ]
; CHECK: %indvars.iv.next = add nuw nsw i64 %indvars.iv, 1
; CHECK: %iv.inc.cmp = icmp slt i64 %indvars.iv.next, [[LEN_SEXT]]
; CHECK: call void (i1, ...) @llvm.experimental.guard(i1 %iv.inc.cmp) [ "deopt"() ]
; CHECK: leave:
%iv = phi i32 [ 0, %entry ], [ %iv.inc, %loop ]
%iv.inc = add i32 %iv, 1
%iv.sext = sext i32 %iv to i64
%iv.inc.cmp = icmp slt i32 %iv.inc, %len
call void(i1, ...) @llvm.experimental.guard(i1 %iv.inc.cmp) [ "deopt"() ]
%becond = icmp ne i32 %iv, %n
br i1 %becond, label %loop, label %leave
leave:
ret void
}
define void @test_3(i1* %cond_buf, i32* %len_buf) {
; CHECK-LABEL: @test_3(
entry:
%len = load i32, i32* %len_buf
%entry.cond = icmp sgt i32 %len, 0
call void(i1, ...) @llvm.experimental.guard(i1 %entry.cond) [ "deopt"() ]
br label %loop
loop:
; CHECK: loop:
; CHECK: call void (i1, ...) @llvm.experimental.guard(i1 true) [ "deopt"() ]
; CHECK: %iv.inc.cmp = icmp slt i32 %iv.inc, %len
; CHECK: call void (i1, ...) @llvm.experimental.guard(i1 %iv.inc.cmp) [ "deopt"() ]
; CHECK: leave:
%iv = phi i32 [ 0, %entry ], [ %iv.inc, %loop ]
%iv.inc = add i32 %iv, 1
%iv.cmp = icmp slt i32 %iv, %len
call void(i1, ...) @llvm.experimental.guard(i1 %iv.cmp) [ "deopt"() ]
%iv.inc.cmp = icmp slt i32 %iv.inc, %len
call void(i1, ...) @llvm.experimental.guard(i1 %iv.inc.cmp) [ "deopt"() ]
%becond = load volatile i1, i1* %cond_buf
br i1 %becond, label %loop, label %leave
leave:
ret void
}
define void @test_4(i1* %cond_buf, i32* %len_buf) {
; CHECK-LABEL: @test_4(
entry:
%len = load i32, i32* %len_buf
%entry.cond = icmp sgt i32 %len, 0
call void(i1, ...) @llvm.experimental.guard(i1 %entry.cond) [ "deopt"() ]
br label %loop
loop:
%iv = phi i32 [ 0, %entry ], [ %iv.inc, %be ]
%iv.inc = add i32 %iv, 1
%cond = load volatile i1, i1* %cond_buf
br i1 %cond, label %left, label %be
left:
; Does not dominate the backedge, so cannot be used in the inductive proof
%iv.inc.cmp = icmp slt i32 %iv.inc, %len
call void(i1, ...) @llvm.experimental.guard(i1 %iv.inc.cmp) [ "deopt"() ]
br label %be
be:
; CHECK: be:
; CHECK-NEXT: %iv.cmp = icmp slt i32 %iv, %len
; CHECK-NEXT: call void (i1, ...) @llvm.experimental.guard(i1 %iv.cmp) [ "deopt"() ]
; CHECK: leave:
%iv.cmp = icmp slt i32 %iv, %len
call void(i1, ...) @llvm.experimental.guard(i1 %iv.cmp) [ "deopt"() ]
%becond = load volatile i1, i1* %cond_buf
br i1 %becond, label %loop, label %leave
leave:
ret void
}