[llvm] d42cfc4 - [SimplifyCFG] Add tests for block speculation with assumes (NFC)

[Nikita Popov via llvm-commits]

Author: Nikita Popov
Date: 2022-11-03T15:46:55+01:00
New Revision: d42cfc4be1562ce7a887842493bf54c5b22e5857

URL: https://github.com/llvm/llvm-project/commit/d42cfc4be1562ce7a887842493bf54c5b22e5857
DIFF: https://github.com/llvm/llvm-project/commit/d42cfc4be1562ce7a887842493bf54c5b22e5857.diff

LOG: [SimplifyCFG] Add tests for block speculation with assumes (NFC)

Added: 
    

Modified: 
    llvm/test/Transforms/SimplifyCFG/assume.ll

Removed: 
    


################################################################################
diff  --git a/llvm/test/Transforms/SimplifyCFG/assume.ll b/llvm/test/Transforms/SimplifyCFG/assume.ll
index ef3e5376f3950..1091f74518a2d 100644
--- a/llvm/test/Transforms/SimplifyCFG/assume.ll
+++ b/llvm/test/Transforms/SimplifyCFG/assume.ll
@@ -1,21 +1,155 @@
+; NOTE: Assertions have been autogenerated by utils/update_test_checks.py
 ; RUN: opt -simplifycfg -simplifycfg-require-and-preserve-domtree=1 -S < %s | FileCheck %s
 
-define void @test1() {
-        call void @llvm.assume(i1 0)
-        ret void
+define void @assume_false_to_unreachable1() {
+; CHECK-LABEL: @assume_false_to_unreachable1(
+; CHECK-NEXT:    unreachable
+;
+  call void @llvm.assume(i1 0)
+  ret void
 
-; CHECK-LABEL: @test1
-; CHECK-NOT: llvm.assume
-; CHECK: unreachable
 }
 
-define void @test2() {
-        call void @llvm.assume(i1 undef)
-        ret void
+define void @assume_undef_to_unreachable() {
+; CHECK-LABEL: @assume_undef_to_unreachable(
+; CHECK-NEXT:    unreachable
+;
+  call void @llvm.assume(i1 undef)
+  ret void
 
-; CHECK-LABEL: @test2
-; CHECK-NOT: llvm.assume
-; CHECK: unreachable
+}
+
+define i32 @speculate_block_with_assume_basic(i1 %c, i32 %x) {
+; CHECK-LABEL: @speculate_block_with_assume_basic(
+; CHECK-NEXT:  entry:
+; CHECK-NEXT:    br i1 [[C:%.*]], label [[IF:%.*]], label [[JOIN:%.*]]
+; CHECK:       if:
+; CHECK-NEXT:    [[CMP:%.*]] = icmp ne i32 [[X:%.*]], 0
+; CHECK-NEXT:    call void @llvm.assume(i1 [[CMP]])
+; CHECK-NEXT:    br label [[JOIN]]
+; CHECK:       join:
+; CHECK-NEXT:    [[PHI:%.*]] = phi i32 [ 0, [[ENTRY:%.*]] ], [ 1, [[IF]] ]
+; CHECK-NEXT:    ret i32 [[PHI]]
+;
+entry:
+  br i1 %c, label %if, label %join
+
+if:
+  %cmp = icmp ne i32 %x, 0
+  call void @llvm.assume(i1 %cmp)
+  br label %join
+
+join:
+  %phi = phi i32 [ 0, %entry ], [ 1, %if ]
+  ret i32 %phi
+}
+
+define i32 @speculate_block_with_assume_extra_instr(i1 %c, i32 %x) {
+; CHECK-LABEL: @speculate_block_with_assume_extra_instr(
+; CHECK-NEXT:  entry:
+; CHECK-NEXT:    br i1 [[C:%.*]], label [[IF:%.*]], label [[JOIN:%.*]]
+; CHECK:       if:
+; CHECK-NEXT:    [[ADD:%.*]] = add i32 [[X:%.*]], 1
+; CHECK-NEXT:    [[CMP:%.*]] = icmp ne i32 [[ADD]], 0
+; CHECK-NEXT:    call void @llvm.assume(i1 [[CMP]])
+; CHECK-NEXT:    br label [[JOIN]]
+; CHECK:       join:
+; CHECK-NEXT:    [[PHI:%.*]] = phi i32 [ 0, [[ENTRY:%.*]] ], [ [[ADD]], [[IF]] ]
+; CHECK-NEXT:    ret i32 [[PHI]]
+;
+entry:
+  br i1 %c, label %if, label %join
+
+if:
+  %add = add i32 %x, 1
+  %cmp = icmp ne i32 %add, 0
+  call void @llvm.assume(i1 %cmp)
+  br label %join
+
+join:
+  %phi = phi i32 [ 0, %entry ], [ %add, %if ]
+  ret i32 %phi
+}
+
+define i32 @speculate_block_with_assume_extra_instrs_too_many(i1 %c, i32 %x) {
+; CHECK-LABEL: @speculate_block_with_assume_extra_instrs_too_many(
+; CHECK-NEXT:  entry:
+; CHECK-NEXT:    br i1 [[C:%.*]], label [[IF:%.*]], label [[JOIN:%.*]]
+; CHECK:       if:
+; CHECK-NEXT:    [[ADD:%.*]] = add i32 [[X:%.*]], 1
+; CHECK-NEXT:    [[ADD2:%.*]] = add i32 [[ADD]], 1
+; CHECK-NEXT:    [[CMP:%.*]] = icmp ne i32 [[ADD2]], 0
+; CHECK-NEXT:    call void @llvm.assume(i1 [[CMP]])
+; CHECK-NEXT:    br label [[JOIN]]
+; CHECK:       join:
+; CHECK-NEXT:    [[PHI:%.*]] = phi i32 [ 0, [[ENTRY:%.*]] ], [ [[ADD2]], [[IF]] ]
+; CHECK-NEXT:    ret i32 [[PHI]]
+;
+entry:
+  br i1 %c, label %if, label %join
+
+if:
+  %add = add i32 %x, 1
+  %add2 = add i32 %add, 1
+  %cmp = icmp ne i32 %add2, 0
+  call void @llvm.assume(i1 %cmp)
+  br label %join
+
+join:
+  %phi = phi i32 [ 0, %entry ], [ %add2, %if ]
+  ret i32 %phi
+}
+
+define i32 @speculate_block_with_assume_extra_instrs_okay(i1 %c, i32 %x) {
+; CHECK-LABEL: @speculate_block_with_assume_extra_instrs_okay(
+; CHECK-NEXT:  entry:
+; CHECK-NEXT:    br i1 [[C:%.*]], label [[IF:%.*]], label [[JOIN:%.*]]
+; CHECK:       if:
+; CHECK-NEXT:    [[ADD:%.*]] = add i32 [[X:%.*]], 1
+; CHECK-NEXT:    [[ADD2:%.*]] = add i32 [[ADD]], 1
+; CHECK-NEXT:    [[CMP:%.*]] = icmp ne i32 [[ADD2]], 0
+; CHECK-NEXT:    call void @llvm.assume(i1 [[CMP]])
+; CHECK-NEXT:    br label [[JOIN]]
+; CHECK:       join:
+; CHECK-NEXT:    [[PHI:%.*]] = phi i32 [ 0, [[ENTRY:%.*]] ], [ [[ADD]], [[IF]] ]
+; CHECK-NEXT:    ret i32 [[PHI]]
+;
+entry:
+  br i1 %c, label %if, label %join
+
+if:
+  %add = add i32 %x, 1
+  %add2 = add i32 %add, 1
+  %cmp = icmp ne i32 %add2, 0
+  call void @llvm.assume(i1 %cmp)
+  br label %join
+
+join:
+  %phi = phi i32 [ 0, %entry ], [ %add, %if ]
+  ret i32 %phi
+}
+
+define i32 @speculate_block_with_assume_operand_bundle(i1 %c, ptr %p) {
+; CHECK-LABEL: @speculate_block_with_assume_operand_bundle(
+; CHECK-NEXT:  entry:
+; CHECK-NEXT:    br i1 [[C:%.*]], label [[IF:%.*]], label [[JOIN:%.*]]
+; CHECK:       if:
+; CHECK-NEXT:    call void @llvm.assume(i1 true) [ "nonnull"(ptr [[P:%.*]]) ]
+; CHECK-NEXT:    br label [[JOIN]]
+; CHECK:       join:
+; CHECK-NEXT:    [[PHI:%.*]] = phi i32 [ 0, [[ENTRY:%.*]] ], [ 1, [[IF]] ]
+; CHECK-NEXT:    ret i32 [[PHI]]
+;
+entry:
+  br i1 %c, label %if, label %join
+
+if:
+  call void @llvm.assume(i1 true) ["nonnull"(ptr %p)]
+  br label %join
+
+join:
+  %phi = phi i32 [ 0, %entry ], [ 1, %if ]
+  ret i32 %phi
 }
 
 declare void @llvm.assume(i1) nounwind