[ValueTracking] Improve isImpliedCondition for matching LHS and Imm RHSs.

llvm-svn: 268636

4 files changed, 151 insertions, 8 deletions

diff --git a/llvm/test/CodeGen/AArch64/addsub.ll b/llvm/test/CodeGen/AArch64/addsub.ll
index d6350a6db0e..c0235cd5d9e 100644
--- a/llvm/test/CodeGen/AArch64/addsub.ll
+++ b/llvm/test/CodeGen/AArch64/addsub.ll
@@ -5,6 +5,7 @@
 ; loads and stores.
 
 @var_i32 = global i32 42
+@var2_i32 = global i32 43
 @var_i64 = global i64 0
 
 ; Add pure 12-bit immediates:
@@ -106,6 +107,7 @@ define void @sub_med() {
 define void @testing() {
 ; CHECK-LABEL: testing:
   %val = load i32, i32* @var_i32
+  %val2 = load i32, i32* @var2_i32
 
 ; CHECK: cmp {{w[0-9]+}}, #4095
 ; CHECK: b.ne [[RET:.?LBB[0-9]+_[0-9]+]]
@@ -117,7 +119,7 @@ test2:
 ; CHECK: b.lo [[RET]]
   %newval2 = add i32 %val, 1
   store i32 %newval2, i32* @var_i32
-  %cmp_pos_big = icmp ult i32 %val, 14610432
+  %cmp_pos_big = icmp ult i32 %val2, 14610432
   br i1 %cmp_pos_big, label %ret, label %test3
 
 test3:
@@ -133,7 +135,7 @@ test4:
 ; CHECK: b.gt [[RET]]
   %newval4 = add i32 %val, 3
   store i32 %newval4, i32* @var_i32
-  %cmp_pos_sgt = icmp sgt i32 %val, 321
+  %cmp_pos_sgt = icmp sgt i32 %val2, 321
   br i1 %cmp_pos_sgt, label %ret, label %test5
 
 test5:
@@ -141,7 +143,7 @@ test5:
 ; CHECK: b.gt [[RET]]
   %newval5 = add i32 %val, 4
   store i32 %newval5, i32* @var_i32
-  %cmp_neg_uge = icmp sgt i32 %val, -444
+  %cmp_neg_uge = icmp sgt i32 %val2, -444
   br i1 %cmp_neg_uge, label %ret, label %test6
 
 test6:
diff --git a/llvm/test/CodeGen/AArch64/combine-comparisons-by-cse.ll b/llvm/test/CodeGen/AArch64/combine-comparisons-by-cse.ll
index 59b4c953ee9..1f8e0efa067 100644
--- a/llvm/test/CodeGen/AArch64/combine-comparisons-by-cse.ll
+++ b/llvm/test/CodeGen/AArch64/combine-comparisons-by-cse.ll
@@ -405,11 +405,11 @@ return:                                           ; preds = %land.lhs.true, %con
 
 define void @cmp_shifted(i32 %in, i32 %lhs, i32 %rhs) {
 ; CHECK-LABEL: cmp_shifted:
-; CHECK: cmp w0, #1
-; [...]
 ; CHECK: cmp w0, #2, lsl #12
+; [...]
+; CHECK: cmp w0, #1
 
-  %tst_low = icmp sgt i32 %in, 0
+  %tst_low = icmp sgt i32 %in, 8191
   br i1 %tst_low, label %true, label %false
 
 true:
@@ -417,7 +417,7 @@ true:
   ret void
 
 false:
-  %tst = icmp sgt i32 %in, 8191
+  %tst = icmp sgt i32 %in, 0
   br i1 %tst, label %truer, label %falser
 
 truer:
diff --git a/llvm/test/Transforms/InstCombine/select-implied.ll b/llvm/test/Transforms/InstCombine/select-implied.ll
index 0616bd97fd3..2100e3eae00 100644
--- a/llvm/test/Transforms/InstCombine/select-implied.ll
+++ b/llvm/test/Transforms/InstCombine/select-implied.ll
@@ -40,7 +40,7 @@ end:
 ; CHECK-LABEL: @test3
 ; CHECK-NOT: select
 ; CHECK: call void @foo(i32 30)
-define void @test3(i32 %a, i32 %b) {
+define void @test3(i32 %a) {
   %cmp1 = icmp ugt i32 %a, 10
   br i1 %cmp1, label %taken, label %end
 
@@ -101,5 +101,23 @@ ret:
   ret void
 }
 
+; A >u 10 implies A >u 9 is true.
+; CHECK-LABEL: @test5
+; CHECK-NOT: select
+; CHECK: call void @foo(i32 30)
+define void @test5(i32 %a) {
+  %cmp1 = icmp ugt i32 %a, 10
+  br i1 %cmp1, label %taken, label %end
+
+taken:
+  %cmp2 = icmp ugt i32 %a, 9
+  %c = select i1 %cmp2, i32 30, i32 0
+  call void @foo(i32 %c)
+  br label %end
+
+end:
+  ret void
+}
+
 declare void @foo(i32)
 declare i32 @bar(i32)
diff --git a/llvm/test/Transforms/SimplifyCFG/implied-cond-matching-imm.ll b/llvm/test/Transforms/SimplifyCFG/implied-cond-matching-imm.ll
new file mode 100644
index 00000000000..60ef8136598
--- /dev/null
+++ b/llvm/test/Transforms/SimplifyCFG/implied-cond-matching-imm.ll
@@ -0,0 +1,123 @@
+; RUN: opt %s -S -simplifycfg | FileCheck %s
+
+; cmp1 implies cmp2 is false
+; CHECK-LABEL: @test1
+; CHECK-NOT: call void @is(i1 true)
+; CHECK: call void @is(i1 false)
+define void @test1(i32 %a) {
+  %cmp1 = icmp eq i32 %a, 0
+  br i1 %cmp1, label %taken, label %untaken
+
+taken:
+  %cmp2 = icmp eq i32 %a, 1
+  br i1 %cmp2, label %istrue, label %isfalse
+
+istrue:
+  call void @is(i1 true)
+  ret void
+
+isfalse:
+  call void @is(i1 false)
+  ret void
+
+untaken:
+  ret void
+}
+
+; cmp1 implies cmp2 is false
+; CHECK-LABEL: @test2
+; CHECK-NOT: call void @is(i1 true)
+; CHECK: call void @is(i1 false)
+define void @test2(i32 %a) {
+  %cmp1 = icmp ugt i32 %a, 5
+  br i1 %cmp1, label %untaken, label %taken
+
+taken:
+  %cmp2 = icmp ugt i32 %a, 6
+  br i1 %cmp2, label %istrue, label %isfalse
+
+istrue:
+  call void @is(i1 true)
+  ret void
+
+isfalse:
+  call void @is(i1 false)
+  ret void
+
+untaken:
+  ret void
+}
+
+; cmp1 implies cmp2 is false
+; CHECK-LABEL: @test3
+; CHECK-NOT: call void @is(i1 true)
+; CHECK: call void @is(i1 false)
+define void @test3(i32 %a) {
+  %cmp1 = icmp ugt i32 %a, 1
+  br i1 %cmp1, label %taken, label %untaken
+
+taken:
+  %cmp2 = icmp eq i32 %a, 0
+  br i1 %cmp2, label %istrue, label %isfalse
+
+istrue:
+  call void @is(i1 true)
+  ret void
+
+isfalse:
+  call void @is(i1 false)
+  ret void
+
+untaken:
+  ret void
+}
+
+; cmp1 implies cmp2 is true
+; CHECK-LABEL: @test4
+; CHECK: call void @is(i1 true)
+; CHECK-NOT: call void @is(i1 false)
+define void @test4(i32 %a) {
+  %cmp1 = icmp sgt i32 %a, 1
+  br i1 %cmp1, label %taken, label %untaken
+
+taken:
+  %cmp2 = icmp ugt i32 %a, 0
+  br i1 %cmp2, label %istrue, label %isfalse
+
+istrue:
+  call void @is(i1 true)
+  ret void
+
+isfalse:
+  call void @is(i1 false)
+  ret void
+
+untaken:
+  ret void
+}
+
+; cmp1 implies cmp2 is true
+; CHECK-LABEL: @test5
+; CHECK: call void @is(i1 true)
+; CHECK-NOT: call void @is(i1 false)
+define void @test5(i32 %a) {
+  %cmp1 = icmp sgt i32 %a, 5
+  br i1 %cmp1, label %taken, label %untaken
+
+taken:
+  %cmp2 = icmp sgt i32 %a, -1
+  br i1 %cmp2, label %istrue, label %isfalse
+
+istrue:
+  call void @is(i1 true)
+  ret void
+
+isfalse:
+  call void @is(i1 false)
+  ret void
+
+untaken:
+  ret void
+}
+
+declare void @is(i1)