From 075e5a2e2b51a8089d916296d48b87880074e544 Mon Sep 17 00:00:00 2001 From: Hans Wennborg Date: Mon, 11 Sep 2017 23:52:02 +0000 Subject: Revert r312898 "[ARM] Use ADDCARRY / SUBCARRY" MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit It caused PR34564. > This is a preparatory step for D34515 and also is being recommitted as its > first version caused PR34045. > > This change: > - makes nodes ISD::ADDCARRY and ISD::SUBCARRY legal for i32 > - lowering is done by first converting the boolean value into the carry flag > using (_, C) ← (ARMISD::ADDC R, -1) and converted back to an integer value > using (R, _) ← (ARMISD::ADDE 0, 0, C). An ARMISD::ADDE between the two > operations does the actual addition. > - for subtraction, given that ISD::SUBCARRY second result is actually a > borrow, we need to invert the value of the second operand and result before > and after using ARMISD::SUBE. We need to invert the carry result of > ARMISD::SUBE to preserve the semantics. > - given that the generic combiner may lower ISD::ADDCARRY and > ISD::SUBCARRYinto ISD::UADDO and ISD::USUBO we need to update their lowering > as well otherwise i64 operations now would require branches. This implies > updating the corresponding test for unsigned. > - add new combiner to remove the redundant conversions from/to carry flags > to/from boolean values (ARMISD::ADDC (ARMISD::ADDE 0, 0, C), -1) → C > - fixes PR34045 > > Differential Revision: https://reviews.llvm.org/D35192 llvm-svn: 312980 --- llvm/test/CodeGen/ARM/intrinsics-overflow.ll | 88 +++++----------------------- 1 file changed, 15 insertions(+), 73 deletions(-) (limited to 'llvm/test/CodeGen/ARM/intrinsics-overflow.ll') diff --git a/llvm/test/CodeGen/ARM/intrinsics-overflow.ll b/llvm/test/CodeGen/ARM/intrinsics-overflow.ll index af555d2240c..af3dd9dd411 100644 --- a/llvm/test/CodeGen/ARM/intrinsics-overflow.ll +++ b/llvm/test/CodeGen/ARM/intrinsics-overflow.ll @@ -1,6 +1,4 @@ -; RUN: llc < %s -mtriple=arm-linux -mcpu=generic -verify-machineinstrs | FileCheck %s --check-prefix=CHECK --check-prefix=ARM -; RUN: llc < %s -mtriple=thumbv6m-eabi -verify-machineinstrs | FileCheck %s --check-prefix=CHECK --check-prefix=THUMBV6 -; RUN: llc < %s -mtriple=thumbv7-eabi -verify-machineinstrs | FileCheck %s --check-prefix=CHECK --check-prefix=THUMBV7 +; RUN: llc < %s -mtriple=arm-linux -mcpu=generic | FileCheck %s define i32 @uadd_overflow(i32 %a, i32 %b) #0 { %sadd = tail call { i32, i1 } @llvm.uadd.with.overflow.i32(i32 %a, i32 %b) @@ -9,19 +7,10 @@ define i32 @uadd_overflow(i32 %a, i32 %b) #0 { ret i32 %2 ; CHECK-LABEL: uadd_overflow: - - ; ARM: adds r[[R0:[0-9]+]], r[[R0]], r[[R1:[0-9]+]] - ; ARM: mov r[[R2:[0-9]+]], #0 - ; ARM: adc r[[R0]], r[[R2]], #0 - - ; THUMBV6: movs r[[R2:[0-9]+]], #0 - ; THUMBV6: adds r[[R0:[0-9]+]], r[[R0]], r[[R1:[0-9]+]] - ; THUMBV6: adcs r[[R2]], r[[R2]] - ; THUMBV6: mov r[[R0]], r[[R2]] - - ; THUMBV7: adds r[[R0:[0-9]+]], r[[R0]], r[[R1:[0-9]+]] - ; THUMBV7: mov.w r[[R2:[0-9]+]], #0 - ; THUMBV7: adc r[[R0]], r[[R2]], #0 + ; CHECK: add r[[R2:[0-9]+]], r[[R0:[0-9]+]], r[[R1:[0-9]+]] + ; CHECK: mov r[[R1]], #1 + ; CHECK: cmp r[[R2]], r[[R0]] + ; CHECK: movhs r[[R1]], #0 } @@ -32,26 +21,10 @@ define i32 @sadd_overflow(i32 %a, i32 %b) #0 { ret i32 %2 ; CHECK-LABEL: sadd_overflow: - - ; ARM: add r[[R2:[0-9]+]], r[[R0:[0-9]+]], r[[R1:[0-9]+]] - ; ARM: mov r[[R1]], #1 - ; ARM: cmp r[[R2]], r[[R0]] - ; ARM: movvc r[[R1]], #0 - - ; THUMBV6: mov r[[R2:[0-9]+]], r[[R0:[0-9]+]] - ; THUMBV6: adds r[[R3:[0-9]+]], r[[R2]], r[[R1:[0-9]+]] - ; THUMBV6: movs r[[R0]], #0 - ; THUMBV6: movs r[[R1]], #1 - ; THUMBV6: cmp r[[R3]], r[[R2]] - ; THUMBV6: bvc .L[[LABEL:.*]] - ; THUMBV6: mov r[[R0]], r[[R1]] - ; THUMBV6: .L[[LABEL]]: - - ; THUMBV7: movs r[[R1]], #1 - ; THUMBV7: cmp r[[R2]], r[[R0]] - ; THUMBV7: it vc - ; THUMBV7: movvc r[[R1]], #0 - ; THUMBV7: mov r[[R0]], r[[R1]] + ; CHECK: add r[[R2:[0-9]+]], r[[R0:[0-9]+]], r[[R1:[0-9]+]] + ; CHECK: mov r[[R1]], #1 + ; CHECK: cmp r[[R2]], r[[R0]] + ; CHECK: movvc r[[R1]], #0 } define i32 @usub_overflow(i32 %a, i32 %b) #0 { @@ -61,26 +34,9 @@ define i32 @usub_overflow(i32 %a, i32 %b) #0 { ret i32 %2 ; CHECK-LABEL: usub_overflow: - - ; ARM: subs r[[R0:[0-9]+]], r[[R0]], r[[R1:[0-9]+]] - ; ARM: mov r[[R2:[0-9]+]], #0 - ; ARM: adc r[[R0]], r[[R2]], #0 - ; ARM: rsb r[[R0]], r[[R0]], #1 - - ; THUMBV6: movs r[[R2:[0-9]+]], #0 - ; THUMBV6: subs r[[R0:[0-9]+]], r[[R0]], r[[R1:[0-9]+]] - ; THUMBV6: adcs r[[R2]], r[[R2]] - ; THUMBV6: movs r[[R0]], #1 - ; THUMBV6: subs r[[R0]], r[[R0]], r[[R2]] - - ; THUMBV7: subs r[[R0:[0-9]+]], r[[R0]], r[[R1:[0-9]+]] - ; THUMBV7: mov.w r[[R2:[0-9]+]], #0 - ; THUMBV7: adc r[[R0]], r[[R2]], #0 - ; THUMBV7: rsb.w r[[R0]], r[[R0]], #1 - - ; We should know that the overflow is just 1 bit, - ; no need to clear any other bit - ; CHECK-NOT: and + ; CHECK: mov r[[R2]], #1 + ; CHECK: cmp r[[R0]], r[[R1]] + ; CHECK: movhs r[[R2]], #0 } define i32 @ssub_overflow(i32 %a, i32 %b) #0 { @@ -90,23 +46,9 @@ define i32 @ssub_overflow(i32 %a, i32 %b) #0 { ret i32 %2 ; CHECK-LABEL: ssub_overflow: - - ; ARM: mov r[[R2]], #1 - ; ARM: cmp r[[R0]], r[[R1]] - ; ARM: movvc r[[R2]], #0 - - ; THUMBV6: movs r[[R0]], #0 - ; THUMBV6: movs r[[R3:[0-9]+]], #1 - ; THUMBV6: cmp r[[R2]], r[[R1:[0-9]+]] - ; THUMBV6: bvc .L[[LABEL:.*]] - ; THUMBV6: mov r[[R0]], r[[R3]] - ; THUMBV6: .L[[LABEL]]: - - ; THUMBV7: movs r[[R2:[0-9]+]], #1 - ; THUMBV7: cmp r[[R0:[0-9]+]], r[[R1:[0-9]+]] - ; THUMBV7: it vc - ; THUMBV7: movvc r[[R2]], #0 - ; THUMBV7: mov r[[R0]], r[[R2]] + ; CHECK: mov r[[R2]], #1 + ; CHECK: cmp r[[R0]], r[[R1]] + ; CHECK: movvc r[[R2]], #0 } declare { i32, i1 } @llvm.uadd.with.overflow.i32(i32, i32) #1 -- cgit v1.2.3