dom-conditions.ll 3.2 KB

123456789101112131415161718192021222324252627282930313233343536373839404142434445464748495051525354555657585960616263646566676869707172737475767778798081828384858687888990919293949596979899100101102103104105106107108109110111112113114115116117118119120121122123124125126127128129130131132133134135136137138139140141142143144145146147148149150151152
  1. ; RUN: opt -instcombine -value-tracking-dom-conditions=1 -S < %s | FileCheck %s
  2. target datalayout = "e-p:64:64:64-p1:16:16:16-p2:32:32:32-p3:64:64:64-i1:8:8-i8:8:8-i16:16:16-i32:32:32-i64:64:64-f32:32:32-f64:64:64-v64:64:64-v128:128:128-a0:0:64-s0:64:64-f80:128:128-n8:16:32:64"
  3. define i1 @test_cmp_ult(i64 %A) {
  4. ; CHECK-LABEL: @test_cmp_ult
  5. entry:
  6. %cmp = icmp ult i64 %A, 64
  7. br i1 %cmp, label %taken, label %untaken
  8. taken:
  9. ; CHECK-LABEL: taken:
  10. ; CHECK-NEXT: ret i1 false
  11. %cmp2 = icmp ugt i64 %A, 64
  12. ret i1 %cmp2
  13. untaken:
  14. ret i1 true
  15. }
  16. define i1 @test_cmp_ule(i64 %A) {
  17. ; CHECK-LABEL: @test_cmp_ule
  18. entry:
  19. %cmp = icmp ule i64 %A, 64
  20. br i1 %cmp, label %taken, label %untaken
  21. taken:
  22. ; CHECK-LABEL: taken:
  23. ; CHECK-NEXT: ret i1 false
  24. %cmp2 = icmp ugt i64 %A, 128
  25. ret i1 %cmp2
  26. untaken:
  27. ret i1 true
  28. }
  29. define i1 @test_cmp_sgt(i32 %A) {
  30. ; CHECK-LABEL: @test_cmp_sgt
  31. entry:
  32. %cmp = icmp sgt i32 %A, 10
  33. br i1 %cmp, label %taken, label %untaken
  34. taken:
  35. ; CHECK-LABEL: taken:
  36. ; CHECK-NEXT: ret i1 true
  37. %cmp2 = icmp sgt i32 %A, -1
  38. ret i1 %cmp2
  39. untaken:
  40. ret i1 true
  41. }
  42. define i64 @test_add_zero_bits(i64 %A) {
  43. ; CHECK-LABEL: @test_add_zero_bits
  44. entry:
  45. %cmp = icmp eq i64 %A, 2
  46. br i1 %cmp, label %taken, label %untaken
  47. taken:
  48. ; CHECK-LABEL: taken:
  49. ; CHECK-NEXT: ret i64 3
  50. %add = add i64 %A, 1
  51. ret i64 %add
  52. untaken:
  53. ret i64 %A
  54. }
  55. define i64 @test_add_nsw(i64 %A) {
  56. ; CHECK-LABEL: @test_add_nsw
  57. entry:
  58. %cmp = icmp ult i64 %A, 20
  59. br i1 %cmp, label %taken, label %untaken
  60. taken:
  61. ; CHECK-LABEL: taken:
  62. ; CHECK-NEXT: %add = add nuw nsw i64 %A, 1
  63. ; CHECK-NEXT: ret i64 %add
  64. %add = add i64 %A, 1
  65. ret i64 %add
  66. untaken:
  67. ret i64 %A
  68. }
  69. ; After sinking the instructions into the if block, check that we
  70. ; can simplify some of them using dominating conditions.
  71. define i32 @test_add_zero_bits_sink(i32 %x) nounwind ssp {
  72. ; CHECK-LABEL: @test_add_zero_bits_sink(
  73. ; CHECK-NOT: sdiv i32
  74. entry:
  75. %a = add nsw i32 %x, 16
  76. %b = sdiv i32 %a, %x
  77. %cmp = icmp ult i32 %x, 7
  78. br i1 %cmp, label %bb1, label %bb2
  79. bb1:
  80. ; CHECK-LABEL: bb1:
  81. ; CHECK-NEXT: or i32 %x, 16
  82. ; CHECK-NEXT: udiv i32
  83. ret i32 %b
  84. bb2:
  85. ret i32 %x
  86. }
  87. ; A condition in the same block gives no information
  88. define i32 @test_neg1(i32 %x) nounwind ssp {
  89. ; CHECK-LABEL: @test_neg1
  90. ; CHECK: add
  91. ; CHECK: sdiv
  92. ; CHECK: icmp
  93. ; CHECK: select
  94. entry:
  95. %a = add nsw i32 %x, 16
  96. %b = sdiv i32 %a, %x
  97. %cmp = icmp ult i32 %x, 7
  98. %ret = select i1 %cmp, i32 %a, i32 %b
  99. ret i32 %ret
  100. }
  101. ; A non-dominating edge gives no information
  102. define i32 @test_neg2(i32 %x) {
  103. ; CHECK-LABEL: @test_neg2
  104. entry:
  105. %cmp = icmp ult i32 %x, 7
  106. br i1 %cmp, label %bb1, label %merge
  107. bb1:
  108. br label %merge
  109. merge:
  110. ; CHECK-LABEL: merge:
  111. ; CHECK: icmp
  112. ; CHECK: select
  113. %cmp2 = icmp ult i32 %x, 7
  114. %ret = select i1 %cmp2, i32 %x, i32 0
  115. ret i32 %ret
  116. }
  117. ; A unconditional branch expressed as a condition one gives no
  118. ; information (and shouldn't trip any asserts.)
  119. define i32 @test_neg3(i32 %x) {
  120. ; CHECK-LABEL: @test_neg3
  121. entry:
  122. %cmp = icmp ult i32 %x, 7
  123. br i1 %cmp, label %merge, label %merge
  124. merge:
  125. ; CHECK-LABEL: merge:
  126. ; CHECK: icmp
  127. ; CHECK: select
  128. %cmp2 = icmp ult i32 %x, 7
  129. %ret = select i1 %cmp2, i32 %x, i32 0
  130. ret i32 %ret
  131. }
  132. declare i32 @bar()