; NOTE: Assertions have been autogenerated by utils/update_test_checks.py ; RUN: opt < %s -passes=instcombine -S | FileCheck %s target datalayout = "n8:16:32:64" ; Eliminating the casts in this testcase (by narrowing the AND operation) ; allows instcombine to realize the function always returns false. define i1 @test1(i32 %A, i32 %B) { ; CHECK-LABEL: @test1( ; CHECK-NEXT: ret i1 false ; %C1 = icmp slt i32 %A, %B %ELIM1 = zext i1 %C1 to i32 %C2 = icmp sgt i32 %A, %B %ELIM2 = zext i1 %C2 to i32 %C3 = and i32 %ELIM1, %ELIM2 %ELIM3 = trunc i32 %C3 to i1 ret i1 %ELIM3 } ; The next 6 (3 logic ops * (scalar+vector)) tests show potential cases for narrowing a bitwise logic op. define i32 @shrink_xor(i64 %a) { ; CHECK-LABEL: @shrink_xor( ; CHECK-NEXT: [[TMP1:%.*]] = trunc i64 [[A:%.*]] to i32 ; CHECK-NEXT: [[TRUNC:%.*]] = xor i32 [[TMP1]], 1 ; CHECK-NEXT: ret i32 [[TRUNC]] ; %xor = xor i64 %a, 1 %trunc = trunc i64 %xor to i32 ret i32 %trunc } ; Vectors (with splat constants) should get the same transform. define <2 x i32> @shrink_xor_vec(<2 x i64> %a) { ; CHECK-LABEL: @shrink_xor_vec( ; CHECK-NEXT: [[TMP1:%.*]] = trunc <2 x i64> [[A:%.*]] to <2 x i32> ; CHECK-NEXT: [[TRUNC:%.*]] = xor <2 x i32> [[TMP1]], <i32 2, i32 2> ; CHECK-NEXT: ret <2 x i32> [[TRUNC]] ; %xor = xor <2 x i64> %a, <i64 2, i64 2> %trunc = trunc <2 x i64> %xor to <2 x i32> ret <2 x i32> %trunc } ; Source and dest types are not in the datalayout. define i3 @shrink_or(i6 %a) { ; CHECK-LABEL: @shrink_or( ; CHECK-NEXT: [[TMP1:%.*]] = trunc i6 [[A:%.*]] to i3 ; CHECK-NEXT: [[TRUNC:%.*]] = or i3 [[TMP1]], 1 ; CHECK-NEXT: ret i3 [[TRUNC]] ; %or = or i6 %a, 33 %trunc = trunc i6 %or to i3 ret i3 %trunc } ; Vectors (with non-splat constants) should get the same transform. define <2 x i8> @shrink_or_vec(<2 x i16> %a) { ; CHECK-LABEL: @shrink_or_vec( ; CHECK-NEXT: [[TMP1:%.*]] = trunc <2 x i16> [[A:%.*]] to <2 x i8> ; CHECK-NEXT: [[TRUNC:%.*]] = or <2 x i8> [[TMP1]], <i8 -1, i8 0> ; CHECK-NEXT: ret <2 x i8> [[TRUNC]] ; %or = or <2 x i16> %a, <i16 -1, i16 256> %trunc = trunc <2 x i16> %or to <2 x i8> ret <2 x i8> %trunc } ; We discriminate against weird types. define i31 @shrink_and(i64 %a) { ; CHECK-LABEL: @shrink_and( ; CHECK-NEXT: [[AND:%.*]] = and i64 [[A:%.*]], 42 ; CHECK-NEXT: [[TRUNC:%.*]] = trunc i64 [[AND]] to i31 ; CHECK-NEXT: ret i31 [[TRUNC]] ; %and = and i64 %a, 42 %trunc = trunc i64 %and to i31 ret i31 %trunc } ; Chop the top of the constant(s) if needed. define <2 x i32> @shrink_and_vec(<2 x i33> %a) { ; CHECK-LABEL: @shrink_and_vec( ; CHECK-NEXT: [[TMP1:%.*]] = trunc <2 x i33> [[A:%.*]] to <2 x i32> ; CHECK-NEXT: [[TRUNC:%.*]] = and <2 x i32> [[TMP1]], <i32 0, i32 6> ; CHECK-NEXT: ret <2 x i32> [[TRUNC]] ; %and = and <2 x i33> %a, <i33 4294967296, i33 6> %trunc = trunc <2 x i33> %and to <2 x i32> ret <2 x i32> %trunc } ; FIXME: ; This is based on an 'any_of' loop construct. ; By narrowing the phi and logic op, we simplify away the zext and the final icmp. define i1 @searchArray1(i32 %needle, i32* %haystack) { ; CHECK-LABEL: @searchArray1( ; CHECK-NEXT: entry: ; CHECK-NEXT: br label [[LOOP:%.*]] ; CHECK: loop: ; CHECK-NEXT: [[INDVAR:%.*]] = phi i32 [ 0, [[ENTRY:%.*]] ], [ [[INDVAR_NEXT:%.*]], [[LOOP]] ] ; CHECK-NEXT: [[FOUND:%.*]] = phi i8 [ 0, [[ENTRY]] ], [ [[OR:%.*]], [[LOOP]] ] ; CHECK-NEXT: [[TMP0:%.*]] = sext i32 [[INDVAR]] to i64 ; CHECK-NEXT: [[IDX:%.*]] = getelementptr i32, i32* [[HAYSTACK:%.*]], i64 [[TMP0]] ; CHECK-NEXT: [[LD:%.*]] = load i32, i32* [[IDX]], align 4 ; CHECK-NEXT: [[CMP1:%.*]] = icmp eq i32 [[LD]], [[NEEDLE:%.*]] ; CHECK-NEXT: [[ZEXT:%.*]] = zext i1 [[CMP1]] to i8 ; CHECK-NEXT: [[OR]] = or i8 [[FOUND]], [[ZEXT]] ; CHECK-NEXT: [[INDVAR_NEXT]] = add i32 [[INDVAR]], 1 ; CHECK-NEXT: [[EXITCOND:%.*]] = icmp eq i32 [[INDVAR_NEXT]], 1000 ; CHECK-NEXT: br i1 [[EXITCOND]], label [[EXIT:%.*]], label [[LOOP]] ; CHECK: exit: ; CHECK-NEXT: [[TOBOOL:%.*]] = icmp ne i8 [[OR]], 0 ; CHECK-NEXT: ret i1 [[TOBOOL]] ; entry: br label %loop loop: %indvar = phi i32 [ 0, %entry ], [ %indvar.next, %loop ] %found = phi i8 [ 0, %entry ], [ %or, %loop ] %idx = getelementptr i32, i32* %haystack, i32 %indvar %ld = load i32, i32* %idx %cmp1 = icmp eq i32 %ld, %needle %zext = zext i1 %cmp1 to i8 %or = or i8 %found, %zext %indvar.next = add i32 %indvar, 1 %exitcond = icmp eq i32 %indvar.next, 1000 br i1 %exitcond, label %exit, label %loop exit: %tobool = icmp ne i8 %or, 0 ret i1 %tobool } ; FIXME: ; This is based on an 'all_of' loop construct. ; By narrowing the phi and logic op, we simplify away the zext and the final icmp. define i1 @searchArray2(i32 %hay, i32* %haystack) { ; CHECK-LABEL: @searchArray2( ; CHECK-NEXT: entry: ; CHECK-NEXT: br label [[LOOP:%.*]] ; CHECK: loop: ; CHECK-NEXT: [[INDVAR:%.*]] = phi i64 [ 0, [[ENTRY:%.*]] ], [ [[INDVAR_NEXT:%.*]], [[LOOP]] ] ; CHECK-NEXT: [[FOUND:%.*]] = phi i8 [ 1, [[ENTRY]] ], [ [[AND:%.*]], [[LOOP]] ] ; CHECK-NEXT: [[IDX:%.*]] = getelementptr i32, i32* [[HAYSTACK:%.*]], i64 [[INDVAR]] ; CHECK-NEXT: [[LD:%.*]] = load i32, i32* [[IDX]], align 4 ; CHECK-NEXT: [[CMP1:%.*]] = icmp eq i32 [[LD]], [[HAY:%.*]] ; CHECK-NEXT: [[ZEXT:%.*]] = zext i1 [[CMP1]] to i8 ; CHECK-NEXT: [[AND]] = and i8 [[FOUND]], [[ZEXT]] ; CHECK-NEXT: [[INDVAR_NEXT]] = add i64 [[INDVAR]], 1 ; CHECK-NEXT: [[EXITCOND:%.*]] = icmp eq i64 [[INDVAR_NEXT]], 1000 ; CHECK-NEXT: br i1 [[EXITCOND]], label [[EXIT:%.*]], label [[LOOP]] ; CHECK: exit: ; CHECK-NEXT: [[TOBOOL:%.*]] = icmp ne i8 [[AND]], 0 ; CHECK-NEXT: ret i1 [[TOBOOL]] ; entry: br label %loop loop: %indvar = phi i64 [ 0, %entry ], [ %indvar.next, %loop ] %found = phi i8 [ 1, %entry ], [ %and, %loop ] %idx = getelementptr i32, i32* %haystack, i64 %indvar %ld = load i32, i32* %idx %cmp1 = icmp eq i32 %ld, %hay %zext = zext i1 %cmp1 to i8 %and = and i8 %found, %zext %indvar.next = add i64 %indvar, 1 %exitcond = icmp eq i64 %indvar.next, 1000 br i1 %exitcond, label %exit, label %loop exit: %tobool = icmp ne i8 %and, 0 ret i1 %tobool } ; FIXME: ; Narrowing should work with an 'xor' and is not limited to bool types. define i32 @shrinkLogicAndPhi1(i8 %x, i1 %cond) { ; CHECK-LABEL: @shrinkLogicAndPhi1( ; CHECK-NEXT: entry: ; CHECK-NEXT: br i1 [[COND:%.*]], label [[IF:%.*]], label [[ENDIF:%.*]] ; CHECK: if: ; CHECK-NEXT: br label [[ENDIF]] ; CHECK: endif: ; CHECK-NEXT: [[PHI:%.*]] = phi i32 [ 21, [[ENTRY:%.*]] ], [ 33, [[IF]] ] ; CHECK-NEXT: [[ZEXT:%.*]] = zext i8 [[X:%.*]] to i32 ; CHECK-NEXT: [[LOGIC:%.*]] = xor i32 [[PHI]], [[ZEXT]] ; CHECK-NEXT: ret i32 [[LOGIC]] ; entry: br i1 %cond, label %if, label %endif if: br label %endif endif: %phi = phi i32 [ 21, %entry], [ 33, %if ] %zext = zext i8 %x to i32 %logic = xor i32 %phi, %zext ret i32 %logic } ; FIXME: ; Narrowing should work with an 'xor' and is not limited to bool types. ; Test that commuting the xor operands does not inhibit optimization. define i32 @shrinkLogicAndPhi2(i8 %x, i1 %cond) { ; CHECK-LABEL: @shrinkLogicAndPhi2( ; CHECK-NEXT: entry: ; CHECK-NEXT: br i1 [[COND:%.*]], label [[IF:%.*]], label [[ENDIF:%.*]] ; CHECK: if: ; CHECK-NEXT: br label [[ENDIF]] ; CHECK: endif: ; CHECK-NEXT: [[PHI:%.*]] = phi i32 [ 21, [[ENTRY:%.*]] ], [ 33, [[IF]] ] ; CHECK-NEXT: [[ZEXT:%.*]] = zext i8 [[X:%.*]] to i32 ; CHECK-NEXT: [[LOGIC:%.*]] = xor i32 [[PHI]], [[ZEXT]] ; CHECK-NEXT: ret i32 [[LOGIC]] ; entry: br i1 %cond, label %if, label %endif if: br label %endif endif: %phi = phi i32 [ 21, %entry], [ 33, %if ] %zext = zext i8 %x to i32 %logic = xor i32 %zext, %phi ret i32 %logic }