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git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@33743 91177308-0d34-0410-b5e6-96231b3b80d8
This commit is contained in:
Evan Cheng 2007-02-01 02:46:20 +00:00
parent ac94c58319
commit 736cefff85
1 changed files with 61 additions and 0 deletions
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61
lib/Target/ARM/README-Thumb.txt
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@ -63,3 +63,64 @@ LPCRELL0:
ldr r0, LCPI1_0
=>
ldr r0, pc, #((LCPI1_0-(LPCRELL0+4))&0xfffffffc)
//===---------------------------------------------------------------------===//
We compiles the following using a jump table.
define i16 @func_entry_2E_ce(i32 %i) {
newFuncRoot:
br label %entry.ce
bb12.exitStub: ; preds = %entry.ce
ret i16 0
bb4.exitStub: ; preds = %entry.ce, %entry.ce, %entry.ce
ret i16 1
bb9.exitStub: ; preds = %entry.ce, %entry.ce, %entry.ce
ret i16 2
bb.exitStub: ; preds = %entry.ce
ret i16 3
entry.ce: ; preds = %newFuncRoot
switch i32 %i, label %bb12.exitStub [
i32 0, label %bb4.exitStub
i32 1, label %bb9.exitStub
i32 2, label %bb4.exitStub
i32 3, label %bb4.exitStub
i32 7, label %bb9.exitStub
i32 8, label %bb.exitStub
i32 9, label %bb9.exitStub
]
}
gcc compiles to:
cmp r0, #9
@ lr needed for prologue
bhi L2
ldr r3, L11
mov r2, #1
mov r1, r2, asl r0
ands r0, r3, r2, asl r0
movne r0, #2
bxne lr
tst r1, #13
beq L9
L3:
mov r0, r2
bx lr
L9:
tst r1, #256
movne r0, #3
bxne lr
L2:
mov r0, #0
bx lr
L12:
.align 2
L11:
.long 642