diff --git a/llvm/test/CodeGen/ARM/sub-from-const-hoisting.ll b/llvm/test/CodeGen/ARM/sub-from-const-hoisting.ll new file mode 100644 index 000000000000..bcdc507eae6b --- /dev/null +++ b/llvm/test/CodeGen/ARM/sub-from-const-hoisting.ll @@ -0,0 +1,60 @@ +; NOTE: Assertions have been autogenerated by utils/update_llc_test_checks.py +; RUN: llc < %s | FileCheck %s + +target datalayout = "e-m:e-p:32:32-Fi8-i64:64-v128:64:128-a:0:32-n32-S64" +target triple = "thumbv6m-arm-none-eabi" + +; From https://reviews.llvm.org/D62266 +; This used to cause an endless loop in DAGCombine, +; since we were hoisting two binops with constants, one constant being opaque, +; which is why they weren't getting constant folded. + +@a = dso_local local_unnamed_addr global i32 0, align 4 +@b = dso_local local_unnamed_addr global i32 0, align 4 + +; Function Attrs: minsize nounwind optsize +define dso_local i32 @c() local_unnamed_addr #0 { +; CHECK-LABEL: c: +; CHECK: @ %bb.0: @ %entry +; CHECK-NEXT: .save {r4, lr} +; CHECK-NEXT: push {r4, lr} +; CHECK-NEXT: ldr r0, .LCPI0_0 +; CHECK-NEXT: ldr r0, [r0] +; CHECK-NEXT: ldr r4, .LCPI0_1 +; CHECK-NEXT: subs r0, r4, r0 +; CHECK-NEXT: adds r0, r0, #1 +; CHECK-NEXT: bl d +; CHECK-NEXT: ldr r0, .LCPI0_2 +; CHECK-NEXT: ldr r0, [r0] +; CHECK-NEXT: cmp r0, r4 +; CHECK-NEXT: ble .LBB0_2 +; CHECK-NEXT: @ %bb.1: @ %if.then +; CHECK-NEXT: bl e +; CHECK-NEXT: .LBB0_2: @ %if.end +; CHECK-NEXT: pop {r4, pc} +; CHECK-NEXT: .p2align 2 +; CHECK-NEXT: @ %bb.3: +; CHECK-NEXT: .LCPI0_0: +; CHECK-NEXT: .long a +; CHECK-NEXT: .LCPI0_1: +; CHECK-NEXT: .long 1999 @ 0x7cf +; CHECK-NEXT: .LCPI0_2: +; CHECK-NEXT: .long b +entry: + %0 = load i32, i32* @a, align 4 + %sub = sub nsw i32 2000, %0 + %call = tail call i32 bitcast (i32 (...)* @d to i32 (i32)*)(i32 %sub) #2 + %1 = load i32, i32* @b, align 4 + %cmp = icmp sgt i32 %1, 1999 + br i1 %cmp, label %if.then, label %if.end + +if.then: ; preds = %entry + %call1 = tail call i32 bitcast (i32 (...)* @e to i32 ()*)() #2 + br label %if.end + +if.end: ; preds = %if.then, %entry + ret i32 undef +} + +declare dso_local i32 @d(...) local_unnamed_addr #1 +declare dso_local i32 @e(...) local_unnamed_addr #1