div-rem-pairs.ll
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; NOTE: Assertions have been autogenerated by utils/update_test_checks.py
; RUN: opt < %s -div-rem-pairs -S -mtriple=powerpc64-unknown-unknown | FileCheck %s
declare void @foo(i32, i32)
define void @decompose_illegal_srem_same_block(i32 %a, i32 %b) {
; CHECK-LABEL: @decompose_illegal_srem_same_block(
; CHECK-NEXT: [[DIV:%.*]] = sdiv i32 [[A:%.*]], [[B:%.*]]
; CHECK-NEXT: [[TMP1:%.*]] = mul i32 [[DIV]], [[B]]
; CHECK-NEXT: [[REM_DECOMPOSED:%.*]] = sub i32 [[A]], [[TMP1]]
; CHECK-NEXT: call void @foo(i32 [[REM_DECOMPOSED]], i32 [[DIV]])
; CHECK-NEXT: ret void
;
%rem = srem i32 %a, %b
%div = sdiv i32 %a, %b
call void @foo(i32 %rem, i32 %div)
ret void
}
define void @decompose_illegal_urem_same_block(i32 %a, i32 %b) {
; CHECK-LABEL: @decompose_illegal_urem_same_block(
; CHECK-NEXT: [[DIV:%.*]] = udiv i32 [[A:%.*]], [[B:%.*]]
; CHECK-NEXT: [[TMP1:%.*]] = mul i32 [[DIV]], [[B]]
; CHECK-NEXT: [[REM_DECOMPOSED:%.*]] = sub i32 [[A]], [[TMP1]]
; CHECK-NEXT: call void @foo(i32 [[REM_DECOMPOSED]], i32 [[DIV]])
; CHECK-NEXT: ret void
;
%div = udiv i32 %a, %b
%rem = urem i32 %a, %b
call void @foo(i32 %rem, i32 %div)
ret void
}
; Hoist and optionally decompose the sdiv because it's safe and free.
; PR31028 - https://bugs.llvm.org/show_bug.cgi?id=31028
define i32 @hoist_sdiv(i32 %a, i32 %b) {
; CHECK-LABEL: @hoist_sdiv(
; CHECK-NEXT: entry:
; CHECK-NEXT: [[DIV:%.*]] = sdiv i32 [[A:%.*]], [[B:%.*]]
; CHECK-NEXT: [[TMP0:%.*]] = mul i32 [[DIV]], [[B]]
; CHECK-NEXT: [[REM_DECOMPOSED:%.*]] = sub i32 [[A]], [[TMP0]]
; CHECK-NEXT: [[CMP:%.*]] = icmp eq i32 [[REM_DECOMPOSED]], 42
; CHECK-NEXT: br i1 [[CMP]], label [[IF:%.*]], label [[END:%.*]]
; CHECK: if:
; CHECK-NEXT: br label [[END]]
; CHECK: end:
; CHECK-NEXT: [[RET:%.*]] = phi i32 [ [[DIV]], [[IF]] ], [ 3, [[ENTRY:%.*]] ]
; CHECK-NEXT: ret i32 [[RET]]
;
entry:
%rem = srem i32 %a, %b
%cmp = icmp eq i32 %rem, 42
br i1 %cmp, label %if, label %end
if:
%div = sdiv i32 %a, %b
br label %end
end:
%ret = phi i32 [ %div, %if ], [ 3, %entry ]
ret i32 %ret
}
; Hoist and optionally decompose the udiv because it's safe and free.
define i64 @hoist_udiv(i64 %a, i64 %b) {
; CHECK-LABEL: @hoist_udiv(
; CHECK-NEXT: entry:
; CHECK-NEXT: [[DIV:%.*]] = udiv i64 [[A:%.*]], [[B:%.*]]
; CHECK-NEXT: [[TMP0:%.*]] = mul i64 [[DIV]], [[B]]
; CHECK-NEXT: [[REM_DECOMPOSED:%.*]] = sub i64 [[A]], [[TMP0]]
; CHECK-NEXT: [[CMP:%.*]] = icmp eq i64 [[REM_DECOMPOSED]], 42
; CHECK-NEXT: br i1 [[CMP]], label [[IF:%.*]], label [[END:%.*]]
; CHECK: if:
; CHECK-NEXT: br label [[END]]
; CHECK: end:
; CHECK-NEXT: [[RET:%.*]] = phi i64 [ [[DIV]], [[IF]] ], [ 3, [[ENTRY:%.*]] ]
; CHECK-NEXT: ret i64 [[RET]]
;
entry:
%rem = urem i64 %a, %b
%cmp = icmp eq i64 %rem, 42
br i1 %cmp, label %if, label %end
if:
%div = udiv i64 %a, %b
br label %end
end:
%ret = phi i64 [ %div, %if ], [ 3, %entry ]
ret i64 %ret
}
; Hoist the srem if it's safe and free, otherwise decompose it.
define i16 @hoist_srem(i16 %a, i16 %b) {
; CHECK-LABEL: @hoist_srem(
; CHECK-NEXT: entry:
; CHECK-NEXT: [[DIV:%.*]] = sdiv i16 [[A:%.*]], [[B:%.*]]
; CHECK-NEXT: [[CMP:%.*]] = icmp eq i16 [[DIV]], 42
; CHECK-NEXT: br i1 [[CMP]], label [[IF:%.*]], label [[END:%.*]]
; CHECK: if:
; CHECK-NEXT: [[TMP0:%.*]] = mul i16 [[DIV]], [[B]]
; CHECK-NEXT: [[REM_DECOMPOSED:%.*]] = sub i16 [[A]], [[TMP0]]
; CHECK-NEXT: br label [[END]]
; CHECK: end:
; CHECK-NEXT: [[RET:%.*]] = phi i16 [ [[REM_DECOMPOSED]], [[IF]] ], [ 3, [[ENTRY:%.*]] ]
; CHECK-NEXT: ret i16 [[RET]]
;
entry:
%div = sdiv i16 %a, %b
%cmp = icmp eq i16 %div, 42
br i1 %cmp, label %if, label %end
if:
%rem = srem i16 %a, %b
br label %end
end:
%ret = phi i16 [ %rem, %if ], [ 3, %entry ]
ret i16 %ret
}
; Hoist the urem if it's safe and free, otherwise decompose it.
define i8 @hoist_urem(i8 %a, i8 %b) {
; CHECK-LABEL: @hoist_urem(
; CHECK-NEXT: entry:
; CHECK-NEXT: [[DIV:%.*]] = udiv i8 [[A:%.*]], [[B:%.*]]
; CHECK-NEXT: [[CMP:%.*]] = icmp eq i8 [[DIV]], 42
; CHECK-NEXT: br i1 [[CMP]], label [[IF:%.*]], label [[END:%.*]]
; CHECK: if:
; CHECK-NEXT: [[TMP0:%.*]] = mul i8 [[DIV]], [[B]]
; CHECK-NEXT: [[REM_DECOMPOSED:%.*]] = sub i8 [[A]], [[TMP0]]
; CHECK-NEXT: br label [[END]]
; CHECK: end:
; CHECK-NEXT: [[RET:%.*]] = phi i8 [ [[REM_DECOMPOSED]], [[IF]] ], [ 3, [[ENTRY:%.*]] ]
; CHECK-NEXT: ret i8 [[RET]]
;
entry:
%div = udiv i8 %a, %b
%cmp = icmp eq i8 %div, 42
br i1 %cmp, label %if, label %end
if:
%rem = urem i8 %a, %b
br label %end
end:
%ret = phi i8 [ %rem, %if ], [ 3, %entry ]
ret i8 %ret
}
; Be careful with RAUW/invalidation if this is a srem-of-srem.
define i32 @srem_of_srem_unexpanded(i32 %X, i32 %Y, i32 %Z) {
; CHECK-LABEL: @srem_of_srem_unexpanded(
; CHECK-NEXT: [[T0:%.*]] = mul nsw i32 [[Z:%.*]], [[Y:%.*]]
; CHECK-NEXT: [[T1:%.*]] = sdiv i32 [[X:%.*]], [[T0]]
; CHECK-NEXT: [[T2:%.*]] = mul nsw i32 [[T0]], [[T1]]
; CHECK-NEXT: [[TMP1:%.*]] = mul i32 [[T1]], [[T0]]
; CHECK-NEXT: [[T3_DECOMPOSED:%.*]] = sub i32 [[X]], [[TMP1]]
; CHECK-NEXT: [[T4:%.*]] = sdiv i32 [[T3_DECOMPOSED]], [[Y]]
; CHECK-NEXT: [[T5:%.*]] = mul nsw i32 [[T4]], [[Y]]
; CHECK-NEXT: [[TMP2:%.*]] = mul i32 [[T4]], [[Y]]
; CHECK-NEXT: [[T6_DECOMPOSED:%.*]] = sub i32 [[T3_DECOMPOSED]], [[TMP2]]
; CHECK-NEXT: ret i32 [[T6_DECOMPOSED]]
;
%t0 = mul nsw i32 %Z, %Y
%t1 = sdiv i32 %X, %t0
%t2 = mul nsw i32 %t0, %t1
%t3 = srem i32 %X, %t0
%t4 = sdiv i32 %t3, %Y
%t5 = mul nsw i32 %t4, %Y
%t6 = srem i32 %t3, %Y
ret i32 %t6
}
define i32 @srem_of_srem_expanded(i32 %X, i32 %Y, i32 %Z) {
; CHECK-LABEL: @srem_of_srem_expanded(
; CHECK-NEXT: [[T0:%.*]] = mul nsw i32 [[Z:%.*]], [[Y:%.*]]
; CHECK-NEXT: [[T1:%.*]] = sdiv i32 [[X:%.*]], [[T0]]
; CHECK-NEXT: [[T2:%.*]] = mul nsw i32 [[T0]], [[T1]]
; CHECK-NEXT: [[T3:%.*]] = sub nsw i32 [[X]], [[T2]]
; CHECK-NEXT: [[T4:%.*]] = sdiv i32 [[T3]], [[Y]]
; CHECK-NEXT: [[T5:%.*]] = mul nsw i32 [[T4]], [[Y]]
; CHECK-NEXT: [[T6:%.*]] = sub nsw i32 [[T3]], [[T5]]
; CHECK-NEXT: ret i32 [[T6]]
;
%t0 = mul nsw i32 %Z, %Y
%t1 = sdiv i32 %X, %t0
%t2 = mul nsw i32 %t0, %t1
%t3 = sub nsw i32 %X, %t2
%t4 = sdiv i32 %t3, %Y
%t5 = mul nsw i32 %t4, %Y
%t6 = sub nsw i32 %t3, %t5
ret i32 %t6
}
; If the ops don't match, don't do anything: signedness.
define i32 @dont_hoist_udiv(i32 %a, i32 %b) {
; CHECK-LABEL: @dont_hoist_udiv(
; CHECK-NEXT: entry:
; CHECK-NEXT: [[REM:%.*]] = srem i32 [[A:%.*]], [[B:%.*]]
; CHECK-NEXT: [[CMP:%.*]] = icmp eq i32 [[REM]], 42
; CHECK-NEXT: br i1 [[CMP]], label [[IF:%.*]], label [[END:%.*]]
; CHECK: if:
; CHECK-NEXT: [[DIV:%.*]] = udiv i32 [[A]], [[B]]
; CHECK-NEXT: br label [[END]]
; CHECK: end:
; CHECK-NEXT: [[RET:%.*]] = phi i32 [ [[DIV]], [[IF]] ], [ 3, [[ENTRY:%.*]] ]
; CHECK-NEXT: ret i32 [[RET]]
;
entry:
%rem = srem i32 %a, %b
%cmp = icmp eq i32 %rem, 42
br i1 %cmp, label %if, label %end
if:
%div = udiv i32 %a, %b
br label %end
end:
%ret = phi i32 [ %div, %if ], [ 3, %entry ]
ret i32 %ret
}
; If the ops don't match, don't do anything: operation.
define i32 @dont_hoist_srem(i32 %a, i32 %b) {
; CHECK-LABEL: @dont_hoist_srem(
; CHECK-NEXT: entry:
; CHECK-NEXT: [[REM:%.*]] = urem i32 [[A:%.*]], [[B:%.*]]
; CHECK-NEXT: [[CMP:%.*]] = icmp eq i32 [[REM]], 42
; CHECK-NEXT: br i1 [[CMP]], label [[IF:%.*]], label [[END:%.*]]
; CHECK: if:
; CHECK-NEXT: [[REM2:%.*]] = srem i32 [[A]], [[B]]
; CHECK-NEXT: br label [[END]]
; CHECK: end:
; CHECK-NEXT: [[RET:%.*]] = phi i32 [ [[REM2]], [[IF]] ], [ 3, [[ENTRY:%.*]] ]
; CHECK-NEXT: ret i32 [[RET]]
;
entry:
%rem = urem i32 %a, %b
%cmp = icmp eq i32 %rem, 42
br i1 %cmp, label %if, label %end
if:
%rem2 = srem i32 %a, %b
br label %end
end:
%ret = phi i32 [ %rem2, %if ], [ 3, %entry ]
ret i32 %ret
}
; If the ops don't match, don't do anything: operands.
define i32 @dont_hoist_sdiv(i32 %a, i32 %b, i32 %c) {
; CHECK-LABEL: @dont_hoist_sdiv(
; CHECK-NEXT: entry:
; CHECK-NEXT: [[REM:%.*]] = srem i32 [[A:%.*]], [[B:%.*]]
; CHECK-NEXT: [[CMP:%.*]] = icmp eq i32 [[REM]], 42
; CHECK-NEXT: br i1 [[CMP]], label [[IF:%.*]], label [[END:%.*]]
; CHECK: if:
; CHECK-NEXT: [[DIV:%.*]] = sdiv i32 [[A]], [[C:%.*]]
; CHECK-NEXT: br label [[END]]
; CHECK: end:
; CHECK-NEXT: [[RET:%.*]] = phi i32 [ [[DIV]], [[IF]] ], [ 3, [[ENTRY:%.*]] ]
; CHECK-NEXT: ret i32 [[RET]]
;
entry:
%rem = srem i32 %a, %b
%cmp = icmp eq i32 %rem, 42
br i1 %cmp, label %if, label %end
if:
%div = sdiv i32 %a, %c
br label %end
end:
%ret = phi i32 [ %div, %if ], [ 3, %entry ]
ret i32 %ret
}
; If the target doesn't have a unified div/rem op for the type, decompose rem in-place to mul+sub.
define i128 @dont_hoist_urem(i128 %a, i128 %b) {
; CHECK-LABEL: @dont_hoist_urem(
; CHECK-NEXT: entry:
; CHECK-NEXT: [[DIV:%.*]] = udiv i128 [[A:%.*]], [[B:%.*]]
; CHECK-NEXT: [[CMP:%.*]] = icmp eq i128 [[DIV]], 42
; CHECK-NEXT: br i1 [[CMP]], label [[IF:%.*]], label [[END:%.*]]
; CHECK: if:
; CHECK-NEXT: [[TMP0:%.*]] = mul i128 [[DIV]], [[B]]
; CHECK-NEXT: [[REM_DECOMPOSED:%.*]] = sub i128 [[A]], [[TMP0]]
; CHECK-NEXT: br label [[END]]
; CHECK: end:
; CHECK-NEXT: [[RET:%.*]] = phi i128 [ [[REM_DECOMPOSED]], [[IF]] ], [ 3, [[ENTRY:%.*]] ]
; CHECK-NEXT: ret i128 [[RET]]
;
entry:
%div = udiv i128 %a, %b
%cmp = icmp eq i128 %div, 42
br i1 %cmp, label %if, label %end
if:
%rem = urem i128 %a, %b
br label %end
end:
%ret = phi i128 [ %rem, %if ], [ 3, %entry ]
ret i128 %ret
}
; We don't hoist if one op does not dominate the other,
; but we could hoist both ops to the common predecessor block?
define i32 @no_domination(i1 %cmp, i32 %a, i32 %b) {
; CHECK-LABEL: @no_domination(
; CHECK-NEXT: entry:
; CHECK-NEXT: br i1 [[CMP:%.*]], label [[IF:%.*]], label [[ELSE:%.*]]
; CHECK: if:
; CHECK-NEXT: [[DIV:%.*]] = sdiv i32 [[A:%.*]], [[B:%.*]]
; CHECK-NEXT: br label [[END:%.*]]
; CHECK: else:
; CHECK-NEXT: [[REM:%.*]] = srem i32 [[A]], [[B]]
; CHECK-NEXT: br label [[END]]
; CHECK: end:
; CHECK-NEXT: [[RET:%.*]] = phi i32 [ [[DIV]], [[IF]] ], [ [[REM]], [[ELSE]] ]
; CHECK-NEXT: ret i32 [[RET]]
;
entry:
br i1 %cmp, label %if, label %else
if:
%div = sdiv i32 %a, %b
br label %end
else:
%rem = srem i32 %a, %b
br label %end
end:
%ret = phi i32 [ %div, %if ], [ %rem, %else ]
ret i32 %ret
}