update_llc_test_checks.py

usage: update_llc_test_checks.py [-h] [-v] [--llc-binary LLC_BINARY]
                                 [--function FUNCTION] [--extra_scrub]
                                 [--x86_scrub_rip] [--no_x86_scrub_rip]
                                 tests [tests ...]

A test case update script. This script is a utility to update LLVM 'llc' based
test cases with new FileCheck patterns. It can either update all of the tests
in the file or a single test function. 

positional arguments:
  tests

optional arguments:
  -h, --help            show this help message and exit
  -v, --verbose         Show verbose output
  --llc-binary LLC_BINARY
                        The "llc" binary to use to generate the test case
  --function FUNCTION   The function in the test file to update
  --extra_scrub         Always use additional regex to further reduce diffs
                        between various subtargets
  --x86_scrub_rip       Use more regex for x86 matching to reduce diffs
                        between various subtargets
  --no_x86_scrub_rip

~/llvm/llvm/utils/update_llc_test_checks.py -v test/CodeGen/AArch64/cgp-usubo.ll

-v 会将结果输出到屏幕，不要-v直接在原文件上进行修改。

[shkzhang@pcom023:~/3410]$ cat pr30640.ll
; RUN: llc -O2  -mtriple=powerpc64-linux-gnu -mcpu=pwr8 < %s | FileCheck %s

define i64 @foo() {
entry:
  ret i64 -3617008641903833651

; CHECK: lis [[REG1:[0-9]+]], -12851
; CHECK: ori [[REG2:[0-9]+]], [[REG1]], 52685
; CHECK: rldimi 3, 3, 32, 0
}

[shkzhang@pcom023:~/3410]$ ~/llvm/llvm/utils/update_llc_test_checks.py pr30640.ll
[shkzhang@pcom023:~/3410]$ cat pr30640.ll
; NOTE: Assertions have been autogenerated by utils/update_llc_test_checks.py
; RUN: llc -O2  -mtriple=powerpc64-linux-gnu -mcpu=pwr8 < %s | FileCheck %s

define i64 @foo() {
; CHECK-LABEL: foo:
; CHECK:       # %bb.0: # %entry
; CHECK-NEXT:    lis 3, -12851                  
; CHECK-NEXT:    ori 3, 3, 52685
; CHECK-NEXT:    rldimi 3, 3, 32, 0
; CHECK-NEXT:    blr
entry:
  ret i64 -3617008641903833651

}

; RUN: llc -O2  -mtriple=powerpc64-linux-gnu -mcpu=pwr8 < %s | FileCheck %s

; CHECK: lis [[REG1:[0-9]+]], -12851
; CHECK: ori [[REG2:[0-9]+]], [[REG1]], 52685
; CHECK: rldimi 3, 3, 32, 0
define i64 @foo() {
entry:
  ret i64 -3617008641903833651

; CHECK: lis [[REG1:[0-9]+]], -12851
; CHECK: ori [[REG2:[0-9]+]], [[REG1]], 52685
; CHECK: rldimi 3, 3, 32, 0
}

; NOTE: Assertions have been autogenerated by utils/update_llc_test_checks.py
; RUN: llc -O2  -mtriple=powerpc64-linux-gnu -mcpu=pwr8 < %s | FileCheck %s

; CHECK: lis [[REG1:[0-9]+]], -12851
; CHECK: ori [[REG2:[0-9]+]], [[REG1]], 52685
; CHECK: rldimi 3, 3, 32, 0
define i64 @foo() {
; CHECK-LABEL: foo:
; CHECK:       # %bb.0: # %entry
; CHECK-NEXT:    lis 3, -12851
; CHECK-NEXT:    ori 3, 3, 52685
; CHECK-NEXT:    rldimi 3, 3, 32, 0
; CHECK-NEXT:    blr
entry:
  ret i64 -3617008641903833651

}