mirror of
https://github.com/c64scene-ar/llvm-6502.git
synced 2024-12-21 00:32:23 +00:00
62baa594d7
HowFarToZero was supposed to use unsigned division in order to calculate the backedge taken count. However, SCEVDivision::divide performs signed division. Unless I am mistaken, no users of SCEVDivision actually want signed arithmetic: switch to udiv and urem. This fixes PR21578. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@222093 91177308-0d34-0410-b5e6-96231b3b80d8
54 lines
1.3 KiB
LLVM
54 lines
1.3 KiB
LLVM
; RUN: opt < %s -scalar-evolution -analyze | FileCheck %s
|
|
|
|
define void @test1(i32 %n) {
|
|
entry:
|
|
%s = mul i32 %n, 96
|
|
br label %loop
|
|
loop:
|
|
%i = phi i32 [ 0, %entry ], [ %i.next, %loop ]
|
|
%i.next = add i32 %i, 32
|
|
%t = icmp ne i32 %i.next, %s
|
|
br i1 %t, label %loop, label %exit
|
|
exit:
|
|
ret void
|
|
|
|
; CHECK-LABEL: @test1
|
|
; CHECK: Loop %loop: backedge-taken count is ((-32 + (96 * %n)) /u 32)
|
|
; CHECK: Loop %loop: max backedge-taken count is ((-32 + (96 * %n)) /u 32)
|
|
}
|
|
|
|
; PR19183
|
|
define i32 @test2(i32 %n) {
|
|
entry:
|
|
%s = and i32 %n, -32
|
|
br label %loop
|
|
loop:
|
|
%i = phi i32 [ 0, %entry ], [ %i.next, %loop ]
|
|
%i.next = add i32 %i, 32
|
|
%t = icmp ne i32 %i.next, %s
|
|
br i1 %t, label %loop, label %exit
|
|
exit:
|
|
ret i32 %i
|
|
|
|
; CHECK-LABEL: @test2
|
|
; CHECK: Loop %loop: backedge-taken count is ((-32 + (32 * (%n /u 32))) /u 32)
|
|
; CHECK: Loop %loop: max backedge-taken count is ((-32 + (32 * (%n /u 32))) /u 32)
|
|
}
|
|
|
|
define void @test3(i32 %n) {
|
|
entry:
|
|
%s = mul i32 %n, 96
|
|
br label %loop
|
|
loop:
|
|
%i = phi i32 [ 0, %entry ], [ %i.next, %loop ]
|
|
%i.next = add i32 %i, 96
|
|
%t = icmp ne i32 %i.next, %s
|
|
br i1 %t, label %loop, label %exit
|
|
exit:
|
|
ret void
|
|
|
|
; CHECK-LABEL: @test3
|
|
; CHECK: Loop %loop: Unpredictable backedge-taken count.
|
|
; CHECK: Loop %loop: Unpredictable max backedge-taken count.
|
|
}
|