[PATCH] D50465: [InstCombine] Optimize redundant 'signed truncation check pattern'.

[Roman Lebedev via Phabricator via llvm-commits]

lebedev.ri added a subscriber: RKSimon.
lebedev.ri added inline comments.


================
Comment at: lib/Transforms/InstCombine/InstCombineAndOrXor.cpp:1404
+  return Builder.CreateICmpULT(X, ConstantInt::get(X->getType(), HighestBit),
+                               I.getName() + ".simplified");
+}
----------------
@RKSimon: if i don't set a name here, the `utils/update_test_checks.py` goes mad,
and produces strange (wrong) check-lines:
```
$ ninja check-llvm-transforms-instcombine -v
[0/1] cd /build/llvm-build-GCC-release/test && /usr/bin/python2.7 /build/llvm-build-GCC-release/./bin/llvm-lit -sv /build/llvm/test/Transforms/InstCombine
FAIL: LLVM :: Transforms/InstCombine/signed-truncation-check.ll (696 of 824)
******************** TEST 'LLVM :: Transforms/InstCombine/signed-truncation-check.ll' FAILED ********************
Script:
--
: 'RUN: at line 2';   /build/llvm-build-GCC-release/bin/opt < /build/llvm/test/Transforms/InstCombine/signed-truncation-check.ll -instcombine -S | /build/llvm-build-GCC-release/bin/FileCheck /build/llvm/test/Transforms/InstCombine/signed-truncation-check.ll
--
Exit Code: 1

Command Output (stderr):
--
/build/llvm/test/Transforms/InstCombine/signed-truncation-check.ll:281:15: error: CHECK-NEXT: expected string not found in input
; CHECK-NEXT: [[TMP1:%.*]] = icmp ult i16 [[TMP1]], 128
              ^
<stdin>:114:2: note: scanning from here
 %1 = icmp ult i16 %tmp1, 128
 ^

--

********************
Testing Time: 5.48s
********************
Failing Tests (1):
    LLVM :: Transforms/InstCombine/signed-truncation-check.ll

  Expected Passes    : 808
  Unsupported Tests  : 15
  Unexpected Failures: 1
FAILED: test/CMakeFiles/check-llvm-transforms-instcombine 
cd /build/llvm-build-GCC-release/test && /usr/bin/python2.7 /build/llvm-build-GCC-release/./bin/llvm-lit -sv /build/llvm/test/Transforms/InstCombine
ninja: build stopped: subcommand failed.
```


Repository:
  rL LLVM

https://reviews.llvm.org/D50465