[InstCombine][NFC] Tests for 'unsigned sub overflow' check
----------------------------------------
Name: unsigned sub, overflow, v0
%sub = sub i8 %x, %y
%ov = icmp ugt i8 %sub, %x
=>
%agg = usub_overflow i8 %x, %y
%sub = extractvalue {i8, i1} %agg, 0
%ov = extractvalue {i8, i1} %agg, 1
Done: 1
Optimization is correct!
----------------------------------------
Name: unsigned sub, no overflow, v0
%sub = sub i8 %x, %y
%ov = icmp ule i8 %sub, %x
=>
%agg = usub_overflow i8 %x, %y
%sub = extractvalue {i8, i1} %agg, 0
%not.ov = extractvalue {i8, i1} %agg, 1
%ov = xor %not.ov, -1
Done: 1
Optimization is correct!
llvm-svn: 371099
2019-09-06 01:40:37 +08:00
|
|
|
; NOTE: Assertions have been autogenerated by utils/update_test_checks.py
|
|
|
|
|
; RUN: opt %s -instcombine -S | FileCheck %s
|
|
|
|
|
|
|
|
|
|
; Fold
|
|
|
|
|
; (%x - %y) u<= %x
|
|
|
|
|
; to
|
|
|
|
|
; @llvm.sub.with.overflow(%x, %y) + extractvalue + not
|
|
|
|
|
|
|
|
|
|
define i1 @t0_basic(i8 %x, i8 %y) {
|
|
|
|
|
; CHECK-LABEL: @t0_basic(
|
[InstCombine] foldICmpBinOp(): consider inverted check in 'unsigned sub overflow' check
A follow-up for r329011.
This may be changed to produce @llvm.sub.with.overflow in a later patch,
but for now just make things more consistent overall.
A few observations stem from this:
* There does not seem to be a similar one-instruction fold for uadd-overflow
* I'm not sure we'll want to canonicalize `B u> A` as `usub.with.overflow`,
so since the `icmp` here no longer refers to `sub`,
reconstructing `usub.with.overflow` will be problematic,
and will likely require standalone pass (similar to DivRemPairs).
https://rise4fun.com/Alive/Zqs
Name: (A - B) u> A --> B u> A
%t0 = sub i8 %A, %B
%r = icmp ugt i8 %t0, %A
=>
%r = icmp ugt i8 %B, %A
Name: (A - B) u<= A --> B u<= A
%t0 = sub i8 %A, %B
%r = icmp ule i8 %t0, %A
=>
%r = icmp ule i8 %B, %A
Name: C u< (C - D) --> C u< D
%t0 = sub i8 %C, %D
%r = icmp ult i8 %C, %t0
=>
%r = icmp ult i8 %C, %D
Name: C u>= (C - D) --> C u>= D
%t0 = sub i8 %C, %D
%r = icmp uge i8 %C, %t0
=>
%r = icmp uge i8 %C, %D
llvm-svn: 371101
2019-09-06 01:41:02 +08:00
|
|
|
; CHECK-NEXT: [[R:%.*]] = icmp ule i8 [[Y:%.*]], [[X:%.*]]
|
[InstCombine][NFC] Tests for 'unsigned sub overflow' check
----------------------------------------
Name: unsigned sub, overflow, v0
%sub = sub i8 %x, %y
%ov = icmp ugt i8 %sub, %x
=>
%agg = usub_overflow i8 %x, %y
%sub = extractvalue {i8, i1} %agg, 0
%ov = extractvalue {i8, i1} %agg, 1
Done: 1
Optimization is correct!
----------------------------------------
Name: unsigned sub, no overflow, v0
%sub = sub i8 %x, %y
%ov = icmp ule i8 %sub, %x
=>
%agg = usub_overflow i8 %x, %y
%sub = extractvalue {i8, i1} %agg, 0
%not.ov = extractvalue {i8, i1} %agg, 1
%ov = xor %not.ov, -1
Done: 1
Optimization is correct!
llvm-svn: 371099
2019-09-06 01:40:37 +08:00
|
|
|
; CHECK-NEXT: ret i1 [[R]]
|
|
|
|
|
;
|
|
|
|
|
%t0 = sub i8 %x, %y
|
|
|
|
|
%r = icmp ule i8 %t0, %x
|
|
|
|
|
ret i1 %r
|
|
|
|
|
}
|
|
|
|
|
|
|
|
|
|
define <2 x i1> @t1_vec(<2 x i8> %x, <2 x i8> %y) {
|
|
|
|
|
; CHECK-LABEL: @t1_vec(
|
[InstCombine] foldICmpBinOp(): consider inverted check in 'unsigned sub overflow' check
A follow-up for r329011.
This may be changed to produce @llvm.sub.with.overflow in a later patch,
but for now just make things more consistent overall.
A few observations stem from this:
* There does not seem to be a similar one-instruction fold for uadd-overflow
* I'm not sure we'll want to canonicalize `B u> A` as `usub.with.overflow`,
so since the `icmp` here no longer refers to `sub`,
reconstructing `usub.with.overflow` will be problematic,
and will likely require standalone pass (similar to DivRemPairs).
https://rise4fun.com/Alive/Zqs
Name: (A - B) u> A --> B u> A
%t0 = sub i8 %A, %B
%r = icmp ugt i8 %t0, %A
=>
%r = icmp ugt i8 %B, %A
Name: (A - B) u<= A --> B u<= A
%t0 = sub i8 %A, %B
%r = icmp ule i8 %t0, %A
=>
%r = icmp ule i8 %B, %A
Name: C u< (C - D) --> C u< D
%t0 = sub i8 %C, %D
%r = icmp ult i8 %C, %t0
=>
%r = icmp ult i8 %C, %D
Name: C u>= (C - D) --> C u>= D
%t0 = sub i8 %C, %D
%r = icmp uge i8 %C, %t0
=>
%r = icmp uge i8 %C, %D
llvm-svn: 371101
2019-09-06 01:41:02 +08:00
|
|
|
; CHECK-NEXT: [[R:%.*]] = icmp ule <2 x i8> [[Y:%.*]], [[X:%.*]]
|
[InstCombine][NFC] Tests for 'unsigned sub overflow' check
----------------------------------------
Name: unsigned sub, overflow, v0
%sub = sub i8 %x, %y
%ov = icmp ugt i8 %sub, %x
=>
%agg = usub_overflow i8 %x, %y
%sub = extractvalue {i8, i1} %agg, 0
%ov = extractvalue {i8, i1} %agg, 1
Done: 1
Optimization is correct!
----------------------------------------
Name: unsigned sub, no overflow, v0
%sub = sub i8 %x, %y
%ov = icmp ule i8 %sub, %x
=>
%agg = usub_overflow i8 %x, %y
%sub = extractvalue {i8, i1} %agg, 0
%not.ov = extractvalue {i8, i1} %agg, 1
%ov = xor %not.ov, -1
Done: 1
Optimization is correct!
llvm-svn: 371099
2019-09-06 01:40:37 +08:00
|
|
|
; CHECK-NEXT: ret <2 x i1> [[R]]
|
|
|
|
|
;
|
|
|
|
|
%t0 = sub <2 x i8> %x, %y
|
|
|
|
|
%r = icmp ule <2 x i8> %t0, %x
|
|
|
|
|
ret <2 x i1> %r
|
|
|
|
|
}
|
|
|
|
|
|
|
|
|
|
; Commutativity
|
|
|
|
|
|
|
|
|
|
define i1 @t2_commutative(i8 %x, i8 %y) {
|
|
|
|
|
; CHECK-LABEL: @t2_commutative(
|
[InstCombine] foldICmpBinOp(): consider inverted check in 'unsigned sub overflow' check
A follow-up for r329011.
This may be changed to produce @llvm.sub.with.overflow in a later patch,
but for now just make things more consistent overall.
A few observations stem from this:
* There does not seem to be a similar one-instruction fold for uadd-overflow
* I'm not sure we'll want to canonicalize `B u> A` as `usub.with.overflow`,
so since the `icmp` here no longer refers to `sub`,
reconstructing `usub.with.overflow` will be problematic,
and will likely require standalone pass (similar to DivRemPairs).
https://rise4fun.com/Alive/Zqs
Name: (A - B) u> A --> B u> A
%t0 = sub i8 %A, %B
%r = icmp ugt i8 %t0, %A
=>
%r = icmp ugt i8 %B, %A
Name: (A - B) u<= A --> B u<= A
%t0 = sub i8 %A, %B
%r = icmp ule i8 %t0, %A
=>
%r = icmp ule i8 %B, %A
Name: C u< (C - D) --> C u< D
%t0 = sub i8 %C, %D
%r = icmp ult i8 %C, %t0
=>
%r = icmp ult i8 %C, %D
Name: C u>= (C - D) --> C u>= D
%t0 = sub i8 %C, %D
%r = icmp uge i8 %C, %t0
=>
%r = icmp uge i8 %C, %D
llvm-svn: 371101
2019-09-06 01:41:02 +08:00
|
|
|
; CHECK-NEXT: [[R:%.*]] = icmp ule i8 [[Y:%.*]], [[X:%.*]]
|
[InstCombine][NFC] Tests for 'unsigned sub overflow' check
----------------------------------------
Name: unsigned sub, overflow, v0
%sub = sub i8 %x, %y
%ov = icmp ugt i8 %sub, %x
=>
%agg = usub_overflow i8 %x, %y
%sub = extractvalue {i8, i1} %agg, 0
%ov = extractvalue {i8, i1} %agg, 1
Done: 1
Optimization is correct!
----------------------------------------
Name: unsigned sub, no overflow, v0
%sub = sub i8 %x, %y
%ov = icmp ule i8 %sub, %x
=>
%agg = usub_overflow i8 %x, %y
%sub = extractvalue {i8, i1} %agg, 0
%not.ov = extractvalue {i8, i1} %agg, 1
%ov = xor %not.ov, -1
Done: 1
Optimization is correct!
llvm-svn: 371099
2019-09-06 01:40:37 +08:00
|
|
|
; CHECK-NEXT: ret i1 [[R]]
|
|
|
|
|
;
|
|
|
|
|
%t0 = sub i8 %x, %y
|
|
|
|
|
%r = icmp uge i8 %x, %t0 ; swapped
|
|
|
|
|
ret i1 %r
|
|
|
|
|
}
|
|
|
|
|
|
|
|
|
|
; Extra-use tests
|
|
|
|
|
|
|
|
|
|
declare void @use8(i8)
|
|
|
|
|
|
|
|
|
|
define i1 @t3_extrause0(i8 %x, i8 %y) {
|
|
|
|
|
; CHECK-LABEL: @t3_extrause0(
|
|
|
|
|
; CHECK-NEXT: [[T0:%.*]] = sub i8 [[X:%.*]], [[Y:%.*]]
|
|
|
|
|
; CHECK-NEXT: call void @use8(i8 [[T0]])
|
[InstCombine] foldICmpBinOp(): consider inverted check in 'unsigned sub overflow' check
A follow-up for r329011.
This may be changed to produce @llvm.sub.with.overflow in a later patch,
but for now just make things more consistent overall.
A few observations stem from this:
* There does not seem to be a similar one-instruction fold for uadd-overflow
* I'm not sure we'll want to canonicalize `B u> A` as `usub.with.overflow`,
so since the `icmp` here no longer refers to `sub`,
reconstructing `usub.with.overflow` will be problematic,
and will likely require standalone pass (similar to DivRemPairs).
https://rise4fun.com/Alive/Zqs
Name: (A - B) u> A --> B u> A
%t0 = sub i8 %A, %B
%r = icmp ugt i8 %t0, %A
=>
%r = icmp ugt i8 %B, %A
Name: (A - B) u<= A --> B u<= A
%t0 = sub i8 %A, %B
%r = icmp ule i8 %t0, %A
=>
%r = icmp ule i8 %B, %A
Name: C u< (C - D) --> C u< D
%t0 = sub i8 %C, %D
%r = icmp ult i8 %C, %t0
=>
%r = icmp ult i8 %C, %D
Name: C u>= (C - D) --> C u>= D
%t0 = sub i8 %C, %D
%r = icmp uge i8 %C, %t0
=>
%r = icmp uge i8 %C, %D
llvm-svn: 371101
2019-09-06 01:41:02 +08:00
|
|
|
; CHECK-NEXT: [[R:%.*]] = icmp uge i8 [[X]], [[Y]]
|
[InstCombine][NFC] Tests for 'unsigned sub overflow' check
----------------------------------------
Name: unsigned sub, overflow, v0
%sub = sub i8 %x, %y
%ov = icmp ugt i8 %sub, %x
=>
%agg = usub_overflow i8 %x, %y
%sub = extractvalue {i8, i1} %agg, 0
%ov = extractvalue {i8, i1} %agg, 1
Done: 1
Optimization is correct!
----------------------------------------
Name: unsigned sub, no overflow, v0
%sub = sub i8 %x, %y
%ov = icmp ule i8 %sub, %x
=>
%agg = usub_overflow i8 %x, %y
%sub = extractvalue {i8, i1} %agg, 0
%not.ov = extractvalue {i8, i1} %agg, 1
%ov = xor %not.ov, -1
Done: 1
Optimization is correct!
llvm-svn: 371099
2019-09-06 01:40:37 +08:00
|
|
|
; CHECK-NEXT: ret i1 [[R]]
|
|
|
|
|
;
|
|
|
|
|
%t0 = sub i8 %x, %y
|
|
|
|
|
call void @use8(i8 %t0)
|
|
|
|
|
%r = icmp ule i8 %t0, %x
|
|
|
|
|
ret i1 %r
|
|
|
|
|
}
|
|
|
|
|
|
|
|
|
|
; Negative tests
|
|
|
|
|
|
|
|
|
|
define i1 @n4_not_commutative(i8 %x, i8 %y) {
|
|
|
|
|
; CHECK-LABEL: @n4_not_commutative(
|
|
|
|
|
; CHECK-NEXT: [[T0:%.*]] = sub i8 [[X:%.*]], [[Y:%.*]]
|
|
|
|
|
; CHECK-NEXT: [[R:%.*]] = icmp ule i8 [[T0]], [[Y]]
|
|
|
|
|
; CHECK-NEXT: ret i1 [[R]]
|
|
|
|
|
;
|
|
|
|
|
%t0 = sub i8 %x, %y
|
|
|
|
|
%r = icmp ule i8 %t0, %y ; can't check against %y.
|
|
|
|
|
ret i1 %r
|
|
|
|
|
}
|
|
|
|
|
|
|
|
|
|
define i1 @n5_wrong_pred0(i8 %x, i8 %y) {
|
|
|
|
|
; CHECK-LABEL: @n5_wrong_pred0(
|
|
|
|
|
; CHECK-NEXT: [[T0:%.*]] = sub i8 [[X:%.*]], [[Y:%.*]]
|
|
|
|
|
; CHECK-NEXT: [[R:%.*]] = icmp ult i8 [[T0]], [[X]]
|
|
|
|
|
; CHECK-NEXT: ret i1 [[R]]
|
|
|
|
|
;
|
|
|
|
|
%t0 = sub i8 %x, %y
|
|
|
|
|
%r = icmp ult i8 %t0, %x
|
|
|
|
|
ret i1 %r
|
|
|
|
|
}
|
|
|
|
|
|
|
|
|
|
define i1 @n6_wrong_pred1(i8 %x, i8 %y) {
|
|
|
|
|
; CHECK-LABEL: @n6_wrong_pred1(
|
|
|
|
|
; CHECK-NEXT: [[T0:%.*]] = sub i8 [[X:%.*]], [[Y:%.*]]
|
|
|
|
|
; CHECK-NEXT: [[R:%.*]] = icmp uge i8 [[T0]], [[X]]
|
|
|
|
|
; CHECK-NEXT: ret i1 [[R]]
|
|
|
|
|
;
|
|
|
|
|
%t0 = sub i8 %x, %y
|
|
|
|
|
%r = icmp uge i8 %t0, %x
|
|
|
|
|
ret i1 %r
|
|
|
|
|
}
|
|
|
|
|
|
|
|
|
|
define i1 @n7_wrong_pred2(i8 %x, i8 %y) {
|
|
|
|
|
; CHECK-LABEL: @n7_wrong_pred2(
|
|
|
|
|
; CHECK-NEXT: [[R:%.*]] = icmp eq i8 [[Y:%.*]], 0
|
|
|
|
|
; CHECK-NEXT: ret i1 [[R]]
|
|
|
|
|
;
|
|
|
|
|
%t0 = sub i8 %x, %y
|
|
|
|
|
%r = icmp eq i8 %t0, %x
|
|
|
|
|
ret i1 %r
|
|
|
|
|
}
|
|
|
|
|
|
|
|
|
|
define i1 @n8_wrong_pred3(i8 %x, i8 %y) {
|
|
|
|
|
; CHECK-LABEL: @n8_wrong_pred3(
|
|
|
|
|
; CHECK-NEXT: [[R:%.*]] = icmp ne i8 [[Y:%.*]], 0
|
|
|
|
|
; CHECK-NEXT: ret i1 [[R]]
|
|
|
|
|
;
|
|
|
|
|
%t0 = sub i8 %x, %y
|
|
|
|
|
%r = icmp ne i8 %t0, %x
|
|
|
|
|
ret i1 %r
|
|
|
|
|
}
|
|
|
|
|
|
|
|
|
|
define i1 @n9_wrong_pred4(i8 %x, i8 %y) {
|
|
|
|
|
; CHECK-LABEL: @n9_wrong_pred4(
|
|
|
|
|
; CHECK-NEXT: [[T0:%.*]] = sub i8 [[X:%.*]], [[Y:%.*]]
|
|
|
|
|
; CHECK-NEXT: [[R:%.*]] = icmp slt i8 [[T0]], [[X]]
|
|
|
|
|
; CHECK-NEXT: ret i1 [[R]]
|
|
|
|
|
;
|
|
|
|
|
%t0 = sub i8 %x, %y
|
|
|
|
|
%r = icmp slt i8 %t0, %x
|
|
|
|
|
ret i1 %r
|
|
|
|
|
}
|
|
|
|
|
|
|
|
|
|
define i1 @n10_wrong_pred5(i8 %x, i8 %y) {
|
|
|
|
|
; CHECK-LABEL: @n10_wrong_pred5(
|
|
|
|
|
; CHECK-NEXT: [[T0:%.*]] = sub i8 [[X:%.*]], [[Y:%.*]]
|
|
|
|
|
; CHECK-NEXT: [[R:%.*]] = icmp sle i8 [[T0]], [[X]]
|
|
|
|
|
; CHECK-NEXT: ret i1 [[R]]
|
|
|
|
|
;
|
|
|
|
|
%t0 = sub i8 %x, %y
|
|
|
|
|
%r = icmp sle i8 %t0, %x
|
|
|
|
|
ret i1 %r
|
|
|
|
|
}
|
|
|
|
|
|
|
|
|
|
define i1 @n11_wrong_pred6(i8 %x, i8 %y) {
|
|
|
|
|
; CHECK-LABEL: @n11_wrong_pred6(
|
|
|
|
|
; CHECK-NEXT: [[T0:%.*]] = sub i8 [[X:%.*]], [[Y:%.*]]
|
|
|
|
|
; CHECK-NEXT: [[R:%.*]] = icmp sgt i8 [[T0]], [[X]]
|
|
|
|
|
; CHECK-NEXT: ret i1 [[R]]
|
|
|
|
|
;
|
|
|
|
|
%t0 = sub i8 %x, %y
|
|
|
|
|
%r = icmp sgt i8 %t0, %x
|
|
|
|
|
ret i1 %r
|
|
|
|
|
}
|
|
|
|
|
|
|
|
|
|
define i1 @n12_wrong_pred7(i8 %x, i8 %y) {
|
|
|
|
|
; CHECK-LABEL: @n12_wrong_pred7(
|
|
|
|
|
; CHECK-NEXT: [[T0:%.*]] = sub i8 [[X:%.*]], [[Y:%.*]]
|
|
|
|
|
; CHECK-NEXT: [[R:%.*]] = icmp sge i8 [[T0]], [[X]]
|
|
|
|
|
; CHECK-NEXT: ret i1 [[R]]
|
|
|
|
|
;
|
|
|
|
|
%t0 = sub i8 %x, %y
|
|
|
|
|
%r = icmp sge i8 %t0, %x
|
|
|
|
|
ret i1 %r
|
|
|
|
|
}
|