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llvm-project/llvm/test/CodeGen/ARM/2012-03-26-FoldImmBug.ll

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ARM has a peephole optimization which looks for a def / use pair. The def produces a 32-bit immediate which is consumed by the use. It tries to fold the immediate by breaking it into two parts and fold them into the immmediate fields of two uses. e.g movw r2, #40885 movt r3, #46540 add r0, r0, r3 => add.w r0, r0, #3019898880 add.w r0, r0, #30146560 ; However, this transformation is incorrect if the user produces a flag. e.g. movw r2, #40885 movt r3, #46540 adds r0, r0, r3 => add.w r0, r0, #3019898880 adds.w r0, r0, #30146560 Note the adds.w may not set the carry flag even if the original sequence would. rdar://11116189 llvm-svn: 153484
2012-03-27 07:31:00 +08:00
; RUN: llc < %s -mtriple=thumbv7-apple-ios -mcpu=cortex-a8 | FileCheck %s
; ARM has a peephole optimization which looks for a def / use pair. The def
; produces a 32-bit immediate which is consumed by the use. It tries to
; fold the immediate by breaking it into two parts and fold them into the
; immmediate fields of two uses. e.g
; movw r2, #40885
; movt r3, #46540
; add r0, r0, r3
; =>
; add.w r0, r0, #3019898880
; add.w r0, r0, #30146560
;
; However, this transformation is incorrect if the user produces a flag. e.g.
; movw r2, #40885
; movt r3, #46540
; adds r0, r0, r3
; =>
; add.w r0, r0, #3019898880
; adds.w r0, r0, #30146560
; Note the adds.w may not set the carry flag even if the original sequence
; would.
;
; rdar://11116189
define i64 @t(i64 %aInput) nounwind {
Mass update to CodeGen tests to use CHECK-LABEL for labels corresponding to function definitions for more informative error messages. No functionality change and all updated tests passed locally. This update was done with the following bash script: find test/CodeGen -name "*.ll" | \ while read NAME; do echo "$NAME" if ! grep -q "^; *RUN: *llc.*debug" $NAME; then TEMP=`mktemp -t temp` cp $NAME $TEMP sed -n "s/^define [^@]*@\([A-Za-z0-9_]*\)(.*$/\1/p" < $NAME | \ while read FUNC; do sed -i '' "s/;\(.*\)\([A-Za-z0-9_-]*\):\( *\)$FUNC: *\$/;\1\2-LABEL:\3$FUNC:/g" $TEMP done sed -i '' "s/;\(.*\)-LABEL-LABEL:/;\1-LABEL:/" $TEMP sed -i '' "s/;\(.*\)-NEXT-LABEL:/;\1-NEXT:/" $TEMP sed -i '' "s/;\(.*\)-NOT-LABEL:/;\1-NOT:/" $TEMP sed -i '' "s/;\(.*\)-DAG-LABEL:/;\1-DAG:/" $TEMP mv $TEMP $NAME fi done llvm-svn: 186280
2013-07-14 14:24:09 +08:00
; CHECK-LABEL: t:
ARM has a peephole optimization which looks for a def / use pair. The def produces a 32-bit immediate which is consumed by the use. It tries to fold the immediate by breaking it into two parts and fold them into the immmediate fields of two uses. e.g movw r2, #40885 movt r3, #46540 add r0, r0, r3 => add.w r0, r0, #3019898880 add.w r0, r0, #30146560 ; However, this transformation is incorrect if the user produces a flag. e.g. movw r2, #40885 movt r3, #46540 adds r0, r0, r3 => add.w r0, r0, #3019898880 adds.w r0, r0, #30146560 Note the adds.w may not set the carry flag even if the original sequence would. rdar://11116189 llvm-svn: 153484
2012-03-27 07:31:00 +08:00
; CHECK: movs [[REG:(r[0-9]+)]], #0
; CHECK: movt [[REG]], #46540
; CHECK: adds r{{[0-9]+}}, r{{[0-9]+}}, [[REG]]
%1 = mul i64 %aInput, 1000000
%2 = add i64 %1, -7952618389194932224
ret i64 %2
}