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| ; NOTE: Assertions have been autogenerated by utils/update_test_checks.py
; RUN: opt -S %s -passes=loop-instsimplify | FileCheck %s
; RUN: opt -S %s -passes='loop-mssa(loop-instsimplify)' -verify-memoryssa | FileCheck %s
; Test very basic folding and propagation occurs within a loop body. This should
; collapse to the loop iteration structure and the LCSSA PHI node.
define i32 @test1(i32 %n, i32 %x) {
; CHECK-LABEL: @test1(
; CHECK-NEXT: entry:
; CHECK-NEXT: br label [[LOOP:%.*]]
; CHECK: loop:
; CHECK-NEXT: [[I:%.*]] = phi i32 [ 0, [[ENTRY:%.*]] ], [ [[I_NEXT:%.*]], [[LOOP]] ]
; CHECK-NEXT: [[I_NEXT]] = add nsw i32 [[I]], 1
; CHECK-NEXT: [[I_CMP:%.*]] = icmp slt i32 [[I_NEXT]], [[N:%.*]]
; CHECK-NEXT: br i1 [[I_CMP]], label [[LOOP]], label [[EXIT:%.*]]
; CHECK: exit:
; CHECK-NEXT: [[X_LCSSA:%.*]] = phi i32 [ [[X:%.*]], [[LOOP]] ]
; CHECK-NEXT: ret i32 [[X_LCSSA]]
;
entry:
br label %loop
loop:
%i = phi i32 [ 0, %entry ], [ %i.next, %loop ]
%x.add = add nsw i32 %x, 0
%x.sub = sub i32 %x.add, 0
%x.and = and i32 %x.sub, -1
%i.next = add nsw i32 %i, 1
%i.cmp = icmp slt i32 %i.next, %n
br i1 %i.cmp, label %loop, label %exit
exit:
%x.lcssa = phi i32 [ %x.and, %loop ]
ret i32 %x.lcssa
}
; Test basic loop structure that still has a simplification feed a prior PHI.
define i32 @test2(i32 %n, i32 %x) {
; CHECK-LABEL: @test2(
; CHECK-NEXT: entry:
; CHECK-NEXT: br label [[LOOP:%.*]]
; CHECK: loop:
; CHECK-NEXT: [[I:%.*]] = phi i32 [ 0, [[ENTRY:%.*]] ], [ [[I_NEXT:%.*]], [[LOOP]] ]
; CHECK-NEXT: [[I_NEXT]] = add nsw i32 [[I]], 1
; CHECK-NEXT: [[I_CMP:%.*]] = icmp slt i32 [[I_NEXT]], [[N:%.*]]
; CHECK-NEXT: br i1 [[I_CMP]], label [[LOOP]], label [[EXIT:%.*]]
; CHECK: exit:
; CHECK-NEXT: [[X_LCSSA:%.*]] = phi i32 [ [[X:%.*]], [[LOOP]] ]
; CHECK-NEXT: ret i32 [[X_LCSSA]]
;
entry:
br label %loop
loop:
%i = phi i32 [ 0, %entry ], [ %i.next, %loop ]
%x.loop = phi i32 [ %x, %entry ], [ %x.next, %loop ]
%x.next = add nsw i32 %x.loop, 0
%i.next = add nsw i32 %i, 1
%i.cmp = icmp slt i32 %i.next, %n
br i1 %i.cmp, label %loop, label %exit
exit:
%x.lcssa = phi i32 [ %x.loop, %loop ]
ret i32 %x.lcssa
}
; Test a diamond CFG with inner PHI nodes.
define i32 @test3(i32 %n, i32 %x) {
; CHECK-LABEL: @test3(
; CHECK-NEXT: entry:
; CHECK-NEXT: br label [[LOOP:%.*]]
; CHECK: loop:
; CHECK-NEXT: [[I:%.*]] = phi i32 [ 0, [[ENTRY:%.*]] ], [ [[I_NEXT:%.*]], [[LOOP_LATCH:%.*]] ]
; CHECK-NEXT: [[X_CMP:%.*]] = icmp slt i32 [[I]], 42
; CHECK-NEXT: br i1 [[X_CMP]], label [[LOOP_LHS:%.*]], label [[LOOP_RHS:%.*]]
; CHECK: loop.lhs:
; CHECK-NEXT: br label [[LOOP_LATCH]]
; CHECK: loop.rhs:
; CHECK-NEXT: br label [[LOOP_LATCH]]
; CHECK: loop.latch:
; CHECK-NEXT: [[I_NEXT]] = add nsw i32 [[I]], 1
; CHECK-NEXT: [[I_CMP:%.*]] = icmp slt i32 [[I_NEXT]], [[N:%.*]]
; CHECK-NEXT: br i1 [[I_CMP]], label [[LOOP]], label [[EXIT:%.*]]
; CHECK: exit:
; CHECK-NEXT: [[X_LCSSA:%.*]] = phi i32 [ [[X:%.*]], [[LOOP_LATCH]] ]
; CHECK-NEXT: ret i32 [[X_LCSSA]]
;
entry:
br label %loop
loop:
%i = phi i32 [ 0, %entry ], [ %i.next, %loop.latch ]
%x.loop = phi i32 [ %x, %entry ], [ %x.phi, %loop.latch ]
%x.add = add nsw i32 %x.loop, 0
%x.cmp = icmp slt i32 %i, 42
br i1 %x.cmp, label %loop.lhs, label %loop.rhs
loop.lhs:
%x.l.add = add nsw i32 %x.add, 0
br label %loop.latch
loop.rhs:
%x.r.sub = sub nsw i32 %x.add, 0
br label %loop.latch
loop.latch:
%x.phi = phi i32 [ %x.l.add, %loop.lhs ], [ %x.r.sub, %loop.rhs ]
%i.next = add nsw i32 %i, 1
%i.cmp = icmp slt i32 %i.next, %n
br i1 %i.cmp, label %loop, label %exit
exit:
%x.lcssa = phi i32 [ %x.loop, %loop.latch ]
ret i32 %x.lcssa
}
; Test an inner loop that is only simplified when processing the outer loop, and
; an outer loop only simplified when processing the inner loop.
define i32 @test4(i32 %n, i32 %m, i32 %x) {
; CHECK-LABEL: @test4(
; CHECK-NEXT: entry:
; CHECK-NEXT: br label [[LOOP:%.*]]
; CHECK: loop:
; CHECK-NEXT: [[I:%.*]] = phi i32 [ 0, [[ENTRY:%.*]] ], [ [[I_NEXT:%.*]], [[LOOP_LATCH:%.*]] ]
; CHECK-NEXT: br label [[LOOP_INNER:%.*]]
; CHECK: loop.inner:
; CHECK-NEXT: [[J:%.*]] = phi i32 [ 0, [[LOOP]] ], [ [[J_NEXT:%.*]], [[LOOP_INNER]] ]
; CHECK-NEXT: [[J_NEXT]] = add nsw i32 [[J]], 1
; CHECK-NEXT: [[J_CMP:%.*]] = icmp slt i32 [[J_NEXT]], [[M:%.*]]
; CHECK-NEXT: br i1 [[J_CMP]], label [[LOOP_INNER]], label [[LOOP_LATCH]]
; CHECK: loop.latch:
; CHECK-NEXT: [[I_NEXT]] = add nsw i32 [[I]], 1
; CHECK-NEXT: [[I_CMP:%.*]] = icmp slt i32 [[I_NEXT]], [[N:%.*]]
; CHECK-NEXT: br i1 [[I_CMP]], label [[LOOP]], label [[EXIT:%.*]]
; CHECK: exit:
; CHECK-NEXT: [[X_LCSSA:%.*]] = phi i32 [ [[X:%.*]], [[LOOP_LATCH]] ]
; CHECK-NEXT: ret i32 [[X_LCSSA]]
;
entry:
br label %loop
loop:
%i = phi i32 [ 0, %entry ], [ %i.next, %loop.latch ]
%x.loop = phi i32 [ %x, %entry ], [ %x.inner.lcssa, %loop.latch ]
%x.add = add nsw i32 %x.loop, 0
br label %loop.inner
loop.inner:
%j = phi i32 [ 0, %loop ], [ %j.next, %loop.inner ]
%x.inner.loop = phi i32 [ %x.add, %loop ], [ %x.inner.add, %loop.inner ]
%x.inner.add = add nsw i32 %x.inner.loop, 0
%j.next = add nsw i32 %j, 1
%j.cmp = icmp slt i32 %j.next, %m
br i1 %j.cmp, label %loop.inner, label %loop.latch
loop.latch:
%x.inner.lcssa = phi i32 [ %x.inner.loop, %loop.inner ]
%i.next = add nsw i32 %i, 1
%i.cmp = icmp slt i32 %i.next, %n
br i1 %i.cmp, label %loop, label %exit
exit:
%x.lcssa = phi i32 [ %x.loop, %loop.latch ]
ret i32 %x.lcssa
}
|