maxjhandsome
/
llvm-project
forked from OSchip/llvm-project
1
0
Fork 0
Code Issues Pull Requests Packages Releases Wiki Activity

[InstCombine] Add additional tests for known non zero (NFC) 

Check conditions that imply non-zero, even if they are not literally
"x != 0".

Using ctlz for testing, as explicit comparison might get folded by
other reasoning.
This commit is contained in:
Nikita Popov 2020-12-25 16:13:42 +01:00
parent a3614a31c4
commit b0e6007c82
1 changed files with 96 additions and 4 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

100
llvm/test/Transforms/InstCombine/known-non-zero.ll
View File

@ -13,7 +13,7 @@ define i32 @test0(i64 %x) {
; CHECK-NEXT: [[C:%.*]] = icmp eq i64 [[X:%.*]], 0
; CHECK-NEXT: br i1 [[C]], label [[EXIT:%.*]], label [[NON_ZERO:%.*]]
; CHECK: non_zero:
; CHECK-NEXT: [[CTZ:%.*]] = call i64 @llvm.cttz.i64(i64 [[X]], i1 true), !range !0
; CHECK-NEXT: [[CTZ:%.*]] = call i64 @llvm.cttz.i64(i64 [[X]], i1 true), [[RNG0:!range !.*]]
; CHECK-NEXT: [[CTZ32:%.*]] = trunc i64 [[CTZ]] to i32
; CHECK-NEXT: br label [[EXIT]]
; CHECK: exit:
@ -40,7 +40,7 @@ define i32 @test1(i64 %x) {
; CHECK-NEXT: [[C:%.*]] = icmp eq i64 [[X:%.*]], 0
; CHECK-NEXT: br i1 [[C]], label [[EXIT:%.*]], label [[NON_ZERO:%.*]]
; CHECK: non_zero:
; CHECK-NEXT: [[CTZ:%.*]] = call i64 @llvm.ctlz.i64(i64 [[X]], i1 true), !range !0
; CHECK-NEXT: [[CTZ:%.*]] = call i64 @llvm.ctlz.i64(i64 [[X]], i1 true), [[RNG0]]
; CHECK-NEXT: [[CTZ32:%.*]] = trunc i64 [[CTZ]] to i32
; CHECK-NEXT: br label [[EXIT]]
; CHECK: exit:
@ -93,8 +93,8 @@ exit:
}
; Test that exposed a bug in the PHI handling after D60846. No folding should happen here!
define void @D60846_misompile(i1* %p) {
; CHECK-LABEL: @D60846_misompile(
define void @D60846_miscompile(i1* %p) {
; CHECK-LABEL: @D60846_miscompile(
; CHECK-NEXT: entry:
; CHECK-NEXT: br label [[LOOP:%.*]]
; CHECK: loop:
@ -133,3 +133,95 @@ common: ; preds = %non_zero, %loop
exit: ; preds = %common
ret void
}
define i64 @test_sgt_zero(i64 %x) {
; CHECK-LABEL: @test_sgt_zero(
; CHECK-NEXT: start:
; CHECK-NEXT: [[C:%.*]] = icmp sgt i64 [[X:%.*]], 0
; CHECK-NEXT: br i1 [[C]], label [[NON_ZERO:%.*]], label [[EXIT:%.*]]
; CHECK: non_zero:
; CHECK-NEXT: [[CTZ:%.*]] = call i64 @llvm.ctlz.i64(i64 [[X]], i1 false), [[RNG0]]
; CHECK-NEXT: ret i64 [[CTZ]]
; CHECK: exit:
; CHECK-NEXT: ret i64 -1
;
start:
%c = icmp sgt i64 %x, 0
br i1 %c, label %non_zero, label %exit
non_zero:
%ctz = call i64 @llvm.ctlz.i64(i64 %x, i1 false)
ret i64 %ctz
exit:
ret i64 -1
}
define i64 @test_slt_neg_ten(i64 %x) {
; CHECK-LABEL: @test_slt_neg_ten(
; CHECK-NEXT: start:
; CHECK-NEXT: [[C:%.*]] = icmp slt i64 [[X:%.*]], -10
; CHECK-NEXT: br i1 [[C]], label [[NON_ZERO:%.*]], label [[EXIT:%.*]]
; CHECK: non_zero:
; CHECK-NEXT: [[CTZ:%.*]] = call i64 @llvm.ctlz.i64(i64 [[X]], i1 false), [[RNG0]]
; CHECK-NEXT: ret i64 [[CTZ]]
; CHECK: exit:
; CHECK-NEXT: ret i64 -1
;
start:
%c = icmp slt i64 %x, -10
br i1 %c, label %non_zero, label %exit
non_zero:
%ctz = call i64 @llvm.ctlz.i64(i64 %x, i1 false)
ret i64 %ctz
exit:
ret i64 -1
}
define i64 @test_slt_ten(i64 %x) {
; CHECK-LABEL: @test_slt_ten(
; CHECK-NEXT: start:
; CHECK-NEXT: [[C:%.*]] = icmp slt i64 [[X:%.*]], 10
; CHECK-NEXT: br i1 [[C]], label [[MAYBE_ZERO:%.*]], label [[EXIT:%.*]]
; CHECK: maybe_zero:
; CHECK-NEXT: [[CTZ:%.*]] = call i64 @llvm.ctlz.i64(i64 [[X]], i1 false), [[RNG0]]
; CHECK-NEXT: ret i64 [[CTZ]]
; CHECK: exit:
; CHECK-NEXT: ret i64 -1
;
start:
%c = icmp slt i64 %x, 10
br i1 %c, label %maybe_zero, label %exit
maybe_zero:
%ctz = call i64 @llvm.ctlz.i64(i64 %x, i1 false)
ret i64 %ctz
exit:
ret i64 -1
}
define i64 @test_ugt_unknown(i64 %x, i64 %y) {
; CHECK-LABEL: @test_ugt_unknown(
; CHECK-NEXT: start:
; CHECK-NEXT: [[C:%.*]] = icmp ugt i64 [[X:%.*]], [[Y:%.*]]
; CHECK-NEXT: br i1 [[C]], label [[NON_ZERO:%.*]], label [[EXIT:%.*]]
; CHECK: non_zero:
; CHECK-NEXT: [[CTZ:%.*]] = call i64 @llvm.ctlz.i64(i64 [[X]], i1 false), [[RNG0]]
; CHECK-NEXT: ret i64 [[CTZ]]
; CHECK: exit:
; CHECK-NEXT: ret i64 -1
;
start:
%c = icmp ugt i64 %x, %y
br i1 %c, label %non_zero, label %exit
non_zero:
%ctz = call i64 @llvm.ctlz.i64(i64 %x, i1 false)
ret i64 %ctz
exit:
ret i64 -1
}