1; NOTE: Assertions have been autogenerated by utils/update_test_checks.py 2; RUN: opt < %s -passes=reassociate,instcombine,dce -S | FileCheck %s 3 4; With sub reassociation, constant folding can eliminate all of the constants. 5define i32 @test1(i32 %A, i32 %B) { 6; CHECK-LABEL: @test1( 7; CHECK-NEXT: [[Z:%.*]] = sub i32 [[A:%.*]], [[B:%.*]] 8; CHECK-NEXT: ret i32 [[Z]] 9; 10 %W = add i32 5, %B 11 %X = add i32 -7, %A 12 %Y = sub i32 %X, %W 13 %Z = add i32 %Y, 12 14 ret i32 %Z 15} 16 17; With sub reassociation, constant folding can eliminate the two 12 constants. 18define i32 @test2(i32 %A, i32 %B, i32 %C, i32 %D) { 19; CHECK-LABEL: @test2( 20; CHECK-NEXT: [[TMP1:%.*]] = add i32 [[B:%.*]], [[A:%.*]] 21; CHECK-NEXT: [[TMP2:%.*]] = add i32 [[TMP1]], [[C:%.*]] 22; CHECK-NEXT: [[Q:%.*]] = sub i32 [[D:%.*]], [[TMP2]] 23; CHECK-NEXT: ret i32 [[Q]] 24; 25 %M = add i32 %A, 12 26 %N = add i32 %M, %B 27 %O = add i32 %N, %C 28 %P = sub i32 %D, %O 29 %Q = add i32 %P, 12 30 ret i32 %Q 31} 32 33