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clang (assertions trunk)
clang (trunk)
clang 10.0.0
clang 10.0.1
clang 11.0.0
clang 11.0.1
clang 12.0.0
clang 12.0.1
clang 13.0.0
clang 14.0.0
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clang 18.1.0
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clang 6.0.0
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clang 8.0.0
clang 9.0.0
llc (assertions trunk)
llc (trunk)
llc 10.0.0
llc 10.0.1
llc 11.0.0
llc 11.0.1
llc 12.0.0
llc 12.0.1
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llc 14.0.0
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llc 9.0.0
opt (assertions trunk)
opt (trunk)
opt 10.0.0
opt 10.0.1
opt 11.0.0
opt 11.0.1
opt 12.0.0
opt 12.0.1
opt 13.0.0
opt 14.0.0
opt 15.0.0
opt 16.0.0
opt 17.0.1
opt 18.1.0
opt 3.2
opt 3.3
opt 3.9.1
opt 4.0.0
opt 4.0.1
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Source code
declare void @show1() declare void @show2() declare void @show3() declare void @show4() @c = external global i32, align 4 define void @check1(i32 %x, i32 %y) { ; CHECK-LABEL: @check1( ; CHECK: br i1 %cmp, ; CHECK-NOT: br i1 %cmp, ; CHECK-NOT: if.else: ; Check that control-dependent-dce is able to infer the value of %cmp ; used at the end of basic block if.then and thus that the IR after ; control-dependent-dce contains only one conditional branch based on ; %cmp in basic block entry. entry: %cmp = icmp slt i32 %x, %y br i1 %cmp, label %if.then, label %if.end3 if.then: ; preds = %entry call void () @show1() br i1 %cmp, label %if.then2, label %if.else if.then2: ; preds = %if.then call void () @show2() br label %if.end if.else: ; preds = %if.then call void () @show3() br label %if.end if.end: ; preds = %if.else, %if.then2 br label %if.end3 if.end3: ; preds = %if.end, %entry ret void } define void @check2(i32 %x, i32 %y) { ; CHECK-LABEL: @check2( ; CHECK: br i1 %cmp, ; CHECK-NOT: br i1 %cmp, ; CHECK-NOT: if.else: ; Check that control-dependent-dce is able to infer the value of %cmp ; used at the end of basic block do.body in a loop and thus that the ; IR after control-dependent-dce contains only one conditional branch ; based on %cmp in basic block entry. entry: %cmp = icmp slt i32 %x, %y br i1 %cmp, label %if.then, label %if.end3 if.then: ; preds = %entry call void () @show1() br label %do.body do.body: ; preds = %do.cond, %if.then call void () @show2() br i1 %cmp, label %if.then2, label %if.else if.then2: ; preds = %do.body call void () @show3() br label %if.end if.else: ; preds = %do.body call void () @show4() br label %if.end if.end: ; preds = %if.else, %if.then2 %0 = load i32, i32* @c, align 4 %dec = add nsw i32 %0, -1 store i32 %dec, i32* @c, align 4 br label %do.cond do.cond: ; preds = %if.end %1 = load i32, i32* @c, align 4 %tobool = icmp ne i32 %1, 0 br i1 %tobool, label %do.body, label %do.end do.end: ; preds = %do.cond br label %if.end3 if.end3: ; preds = %do.end, %entry ret void }
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