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[InstSimplify][NFC] Tests for skipping 'div-by-0' checks before inverted @llvm.umul.with.overflow It would be already handled by the non-inverted case if we were hoisting the `not` in InstCombine, but we don't (granted, we don't sink it in this case either), so this is a separate case. llvm-svn: 366801
2019-07-23 20:42:49 +08:00
; NOTE: Assertions have been autogenerated by utils/update_test_checks.py
; RUN: opt %s -instsimplify -S | FileCheck %s
declare { i4, i1 } @llvm.umul.with.overflow.i4(i4, i4) #1
define i1 @t0_umul(i4 %size, i4 %nmemb) {
; CHECK-LABEL: @t0_umul(
[InstSimplify] Drop leftover "division-by-zero guard" around `@llvm.umul.with.overflow` inverted overflow bit Summary: Now that with D65143/D65144 we've produce `@llvm.umul.with.overflow`, and with D65147 we've flattened the CFG, we now can see that the guard may have been there to prevent division by zero is redundant. We can simply drop it: ``` ---------------------------------------- Name: no overflow or zero %iszero = icmp eq i4 %y, 0 %umul = smul_overflow i4 %x, %y %umul.ov = extractvalue {i4, i1} %umul, 1 %umul.ov.not = xor %umul.ov, -1 %retval.0 = or i1 %iszero, %umul.ov.not ret i1 %retval.0 => %iszero = icmp eq i4 %y, 0 %umul = smul_overflow i4 %x, %y %umul.ov = extractvalue {i4, i1} %umul, 1 %umul.ov.not = xor %umul.ov, -1 %retval.0 = or i1 %iszero, %umul.ov.not ret i1 %umul.ov.not Done: 1 Optimization is correct! ``` Note that this is inverted from what we have in a previous patch, here we are looking for the inverted overflow bit. And that inversion is kinda problematic - given this particular pattern we neither hoist that `not` closer to `ret` (then the pattern would have been identical to the one without inversion, and would have been handled by the previous patch), neither do the opposite transform. But regardless, we should handle this too. I've filled [[ https://bugs.llvm.org/show_bug.cgi?id=42720 | PR42720 ]]. Reviewers: nikic, spatel, xbolva00, RKSimon Reviewed By: spatel Subscribers: hiraditya, llvm-commits Tags: #llvm Differential Revision: https://reviews.llvm.org/D65151 llvm-svn: 370351
2019-08-29 20:48:04 +08:00
; CHECK-NEXT: [[UMUL:%.*]] = tail call { i4, i1 } @llvm.umul.with.overflow.i4(i4 [[SIZE:%.*]], i4 [[NMEMB:%.*]])
[InstSimplify][NFC] Tests for skipping 'div-by-0' checks before inverted @llvm.umul.with.overflow It would be already handled by the non-inverted case if we were hoisting the `not` in InstCombine, but we don't (granted, we don't sink it in this case either), so this is a separate case. llvm-svn: 366801
2019-07-23 20:42:49 +08:00
; CHECK-NEXT: [[UMUL_OV:%.*]] = extractvalue { i4, i1 } [[UMUL]], 1
; CHECK-NEXT: [[PHITMP:%.*]] = xor i1 [[UMUL_OV]], true
[InstSimplify] Drop leftover "division-by-zero guard" around `@llvm.umul.with.overflow` inverted overflow bit Summary: Now that with D65143/D65144 we've produce `@llvm.umul.with.overflow`, and with D65147 we've flattened the CFG, we now can see that the guard may have been there to prevent division by zero is redundant. We can simply drop it: ``` ---------------------------------------- Name: no overflow or zero %iszero = icmp eq i4 %y, 0 %umul = smul_overflow i4 %x, %y %umul.ov = extractvalue {i4, i1} %umul, 1 %umul.ov.not = xor %umul.ov, -1 %retval.0 = or i1 %iszero, %umul.ov.not ret i1 %retval.0 => %iszero = icmp eq i4 %y, 0 %umul = smul_overflow i4 %x, %y %umul.ov = extractvalue {i4, i1} %umul, 1 %umul.ov.not = xor %umul.ov, -1 %retval.0 = or i1 %iszero, %umul.ov.not ret i1 %umul.ov.not Done: 1 Optimization is correct! ``` Note that this is inverted from what we have in a previous patch, here we are looking for the inverted overflow bit. And that inversion is kinda problematic - given this particular pattern we neither hoist that `not` closer to `ret` (then the pattern would have been identical to the one without inversion, and would have been handled by the previous patch), neither do the opposite transform. But regardless, we should handle this too. I've filled [[ https://bugs.llvm.org/show_bug.cgi?id=42720 | PR42720 ]]. Reviewers: nikic, spatel, xbolva00, RKSimon Reviewed By: spatel Subscribers: hiraditya, llvm-commits Tags: #llvm Differential Revision: https://reviews.llvm.org/D65151 llvm-svn: 370351
2019-08-29 20:48:04 +08:00
; CHECK-NEXT: ret i1 [[PHITMP]]
[InstSimplify][NFC] Tests for skipping 'div-by-0' checks before inverted @llvm.umul.with.overflow It would be already handled by the non-inverted case if we were hoisting the `not` in InstCombine, but we don't (granted, we don't sink it in this case either), so this is a separate case. llvm-svn: 366801
2019-07-23 20:42:49 +08:00
;
%cmp = icmp eq i4 %size, 0
%umul = tail call { i4, i1 } @llvm.umul.with.overflow.i4(i4 %size, i4 %nmemb)
%umul.ov = extractvalue { i4, i1 } %umul, 1
%phitmp = xor i1 %umul.ov, true
%or = or i1 %cmp, %phitmp
ret i1 %or
}
define i1 @t1_commutative(i4 %size, i4 %nmemb) {
; CHECK-LABEL: @t1_commutative(
[InstSimplify] Drop leftover "division-by-zero guard" around `@llvm.umul.with.overflow` inverted overflow bit Summary: Now that with D65143/D65144 we've produce `@llvm.umul.with.overflow`, and with D65147 we've flattened the CFG, we now can see that the guard may have been there to prevent division by zero is redundant. We can simply drop it: ``` ---------------------------------------- Name: no overflow or zero %iszero = icmp eq i4 %y, 0 %umul = smul_overflow i4 %x, %y %umul.ov = extractvalue {i4, i1} %umul, 1 %umul.ov.not = xor %umul.ov, -1 %retval.0 = or i1 %iszero, %umul.ov.not ret i1 %retval.0 => %iszero = icmp eq i4 %y, 0 %umul = smul_overflow i4 %x, %y %umul.ov = extractvalue {i4, i1} %umul, 1 %umul.ov.not = xor %umul.ov, -1 %retval.0 = or i1 %iszero, %umul.ov.not ret i1 %umul.ov.not Done: 1 Optimization is correct! ``` Note that this is inverted from what we have in a previous patch, here we are looking for the inverted overflow bit. And that inversion is kinda problematic - given this particular pattern we neither hoist that `not` closer to `ret` (then the pattern would have been identical to the one without inversion, and would have been handled by the previous patch), neither do the opposite transform. But regardless, we should handle this too. I've filled [[ https://bugs.llvm.org/show_bug.cgi?id=42720 | PR42720 ]]. Reviewers: nikic, spatel, xbolva00, RKSimon Reviewed By: spatel Subscribers: hiraditya, llvm-commits Tags: #llvm Differential Revision: https://reviews.llvm.org/D65151 llvm-svn: 370351
2019-08-29 20:48:04 +08:00
; CHECK-NEXT: [[UMUL:%.*]] = tail call { i4, i1 } @llvm.umul.with.overflow.i4(i4 [[SIZE:%.*]], i4 [[NMEMB:%.*]])
[InstSimplify][NFC] Tests for skipping 'div-by-0' checks before inverted @llvm.umul.with.overflow It would be already handled by the non-inverted case if we were hoisting the `not` in InstCombine, but we don't (granted, we don't sink it in this case either), so this is a separate case. llvm-svn: 366801
2019-07-23 20:42:49 +08:00
; CHECK-NEXT: [[UMUL_OV:%.*]] = extractvalue { i4, i1 } [[UMUL]], 1
; CHECK-NEXT: [[PHITMP:%.*]] = xor i1 [[UMUL_OV]], true
[InstSimplify] Drop leftover "division-by-zero guard" around `@llvm.umul.with.overflow` inverted overflow bit Summary: Now that with D65143/D65144 we've produce `@llvm.umul.with.overflow`, and with D65147 we've flattened the CFG, we now can see that the guard may have been there to prevent division by zero is redundant. We can simply drop it: ``` ---------------------------------------- Name: no overflow or zero %iszero = icmp eq i4 %y, 0 %umul = smul_overflow i4 %x, %y %umul.ov = extractvalue {i4, i1} %umul, 1 %umul.ov.not = xor %umul.ov, -1 %retval.0 = or i1 %iszero, %umul.ov.not ret i1 %retval.0 => %iszero = icmp eq i4 %y, 0 %umul = smul_overflow i4 %x, %y %umul.ov = extractvalue {i4, i1} %umul, 1 %umul.ov.not = xor %umul.ov, -1 %retval.0 = or i1 %iszero, %umul.ov.not ret i1 %umul.ov.not Done: 1 Optimization is correct! ``` Note that this is inverted from what we have in a previous patch, here we are looking for the inverted overflow bit. And that inversion is kinda problematic - given this particular pattern we neither hoist that `not` closer to `ret` (then the pattern would have been identical to the one without inversion, and would have been handled by the previous patch), neither do the opposite transform. But regardless, we should handle this too. I've filled [[ https://bugs.llvm.org/show_bug.cgi?id=42720 | PR42720 ]]. Reviewers: nikic, spatel, xbolva00, RKSimon Reviewed By: spatel Subscribers: hiraditya, llvm-commits Tags: #llvm Differential Revision: https://reviews.llvm.org/D65151 llvm-svn: 370351
2019-08-29 20:48:04 +08:00
; CHECK-NEXT: ret i1 [[PHITMP]]
[InstSimplify][NFC] Tests for skipping 'div-by-0' checks before inverted @llvm.umul.with.overflow It would be already handled by the non-inverted case if we were hoisting the `not` in InstCombine, but we don't (granted, we don't sink it in this case either), so this is a separate case. llvm-svn: 366801
2019-07-23 20:42:49 +08:00
;
%cmp = icmp eq i4 %size, 0
%umul = tail call { i4, i1 } @llvm.umul.with.overflow.i4(i4 %size, i4 %nmemb)
%umul.ov = extractvalue { i4, i1 } %umul, 1
%phitmp = xor i1 %umul.ov, true
%or = or i1 %phitmp, %cmp ; swapped
ret i1 %or
}
define i1 @n2_wrong_size(i4 %size0, i4 %size1, i4 %nmemb) {
; CHECK-LABEL: @n2_wrong_size(
; CHECK-NEXT: [[CMP:%.*]] = icmp eq i4 [[SIZE1:%.*]], 0
; CHECK-NEXT: [[UMUL:%.*]] = tail call { i4, i1 } @llvm.umul.with.overflow.i4(i4 [[SIZE0:%.*]], i4 [[NMEMB:%.*]])
; CHECK-NEXT: [[UMUL_OV:%.*]] = extractvalue { i4, i1 } [[UMUL]], 1
; CHECK-NEXT: [[PHITMP:%.*]] = xor i1 [[UMUL_OV]], true
; CHECK-NEXT: [[OR:%.*]] = or i1 [[CMP]], [[PHITMP]]
; CHECK-NEXT: ret i1 [[OR]]
;
%cmp = icmp eq i4 %size1, 0 ; not %size0
%umul = tail call { i4, i1 } @llvm.umul.with.overflow.i4(i4 %size0, i4 %nmemb)
%umul.ov = extractvalue { i4, i1 } %umul, 1
%phitmp = xor i1 %umul.ov, true
%or = or i1 %cmp, %phitmp
ret i1 %or
}
define i1 @n3_wrong_pred(i4 %size, i4 %nmemb) {
; CHECK-LABEL: @n3_wrong_pred(
; CHECK-NEXT: [[CMP:%.*]] = icmp ne i4 [[SIZE:%.*]], 0
; CHECK-NEXT: [[UMUL:%.*]] = tail call { i4, i1 } @llvm.umul.with.overflow.i4(i4 [[SIZE]], i4 [[NMEMB:%.*]])
; CHECK-NEXT: [[UMUL_OV:%.*]] = extractvalue { i4, i1 } [[UMUL]], 1
; CHECK-NEXT: [[PHITMP:%.*]] = xor i1 [[UMUL_OV]], true
; CHECK-NEXT: [[OR:%.*]] = or i1 [[CMP]], [[PHITMP]]
; CHECK-NEXT: ret i1 [[OR]]
;
%cmp = icmp ne i4 %size, 0 ; not 'eq'
%umul = tail call { i4, i1 } @llvm.umul.with.overflow.i4(i4 %size, i4 %nmemb)
%umul.ov = extractvalue { i4, i1 } %umul, 1
%phitmp = xor i1 %umul.ov, true
%or = or i1 %cmp, %phitmp
ret i1 %or
}
define i1 @n4_not_and(i4 %size, i4 %nmemb) {
; CHECK-LABEL: @n4_not_and(
; CHECK-NEXT: [[CMP:%.*]] = icmp eq i4 [[SIZE:%.*]], 0
; CHECK-NEXT: [[UMUL:%.*]] = tail call { i4, i1 } @llvm.umul.with.overflow.i4(i4 [[SIZE]], i4 [[NMEMB:%.*]])
; CHECK-NEXT: [[UMUL_OV:%.*]] = extractvalue { i4, i1 } [[UMUL]], 1
; CHECK-NEXT: [[PHITMP:%.*]] = xor i1 [[UMUL_OV]], true
; CHECK-NEXT: [[OR:%.*]] = and i1 [[CMP]], [[PHITMP]]
; CHECK-NEXT: ret i1 [[OR]]
;
%cmp = icmp eq i4 %size, 0
%umul = tail call { i4, i1 } @llvm.umul.with.overflow.i4(i4 %size, i4 %nmemb)
%umul.ov = extractvalue { i4, i1 } %umul, 1
%phitmp = xor i1 %umul.ov, true
%or = and i1 %cmp, %phitmp ; not 'or'
ret i1 %or
}
define i1 @n5_not_zero(i4 %size, i4 %nmemb) {
; CHECK-LABEL: @n5_not_zero(
; CHECK-NEXT: [[CMP:%.*]] = icmp eq i4 [[SIZE:%.*]], 1
; CHECK-NEXT: [[UMUL:%.*]] = tail call { i4, i1 } @llvm.umul.with.overflow.i4(i4 [[SIZE]], i4 [[NMEMB:%.*]])
; CHECK-NEXT: [[UMUL_OV:%.*]] = extractvalue { i4, i1 } [[UMUL]], 1
; CHECK-NEXT: [[PHITMP:%.*]] = xor i1 [[UMUL_OV]], true
; CHECK-NEXT: [[OR:%.*]] = or i1 [[CMP]], [[PHITMP]]
; CHECK-NEXT: ret i1 [[OR]]
;
%cmp = icmp eq i4 %size, 1 ; should be '0'
%umul = tail call { i4, i1 } @llvm.umul.with.overflow.i4(i4 %size, i4 %nmemb)
%umul.ov = extractvalue { i4, i1 } %umul, 1
%phitmp = xor i1 %umul.ov, true
%or = or i1 %cmp, %phitmp
ret i1 %or
}