142 lines
4.8 KiB
LLVM
142 lines
4.8 KiB
LLVM
|
; RUN: llc -mtriple=thumbv8m.base-eabi -mattr=+execute-only %s -o - | FileCheck --check-prefixes=CHECK,CHECK-MOVW %s
|
||
|
; RUN: llc -mtriple=thumbv6m-eabi -mattr=+execute-only %s -o - | FileCheck --check-prefixes=CHECK,CHECK-NOMOVW %s
|
||
|
|
||
|
; Largest offset that fits into sp-relative ldr
|
||
|
; CHECK-LABEL: ldr_range_end:
|
||
|
; CHECK: ldr {{r[0-9]+}}, [sp, #1020]
|
||
|
define i32 @ldr_range_end() {
|
||
|
entry:
|
||
|
%var = alloca i32, align 4
|
||
|
%arr = alloca [1020 x i8], align 4
|
||
|
%0 = load i32, ptr %var, align 4
|
||
|
ret i32 %0
|
||
|
}
|
||
|
|
||
|
; Smallest offset that fits into add+ldr
|
||
|
; CHECK-LABEL: add_ldr_range_start:
|
||
|
; CHECK: add [[REG:r[0-9]+]], sp, #900
|
||
|
; CHECK-NEXT: ldr {{r[0-9]+}}, [[[REG]], #124]
|
||
|
define i32 @add_ldr_range_start() {
|
||
|
entry:
|
||
|
%var = alloca i32, align 4
|
||
|
%arr = alloca [1024 x i8], align 4
|
||
|
%0 = load i32, ptr %var, align 4
|
||
|
ret i32 %0
|
||
|
}
|
||
|
|
||
|
; Largest offset that fits into add+ldr
|
||
|
; CHECK-LABEL: add_ldr_range_end:
|
||
|
; CHECK: add [[REG:r[0-9]+]], sp, #1020
|
||
|
; CHECK-NEXT: ldr {{r[0-9]+}}, [[[REG]], #124]
|
||
|
define i32 @add_ldr_range_end() {
|
||
|
entry:
|
||
|
%var = alloca i32, align 4
|
||
|
%arr = alloca [1144 x i8], align 4
|
||
|
%0 = load i32, ptr %var, align 4
|
||
|
ret i32 %0
|
||
|
}
|
||
|
|
||
|
; Smallest offset where we start using mov32. If we don't have movw then using
|
||
|
; an ldr offset means we save an add.
|
||
|
; CHECK-LABEL: mov32_range_start:
|
||
|
; CHECK-MOVW: movw [[REG:r[0-9]+]], #1148
|
||
|
; CHECK-NOMOVW: movs [[REG:r[0-9]+]], #4
|
||
|
; CHECK-NOMOVW-NEXT: lsls [[REG]], [[REG]], #8
|
||
|
; CHECK-NEXT: add [[REG]], sp
|
||
|
; CHECK-MOVW-NEXT: ldr {{r[0-9]+}}, [[[REG]]]
|
||
|
; CHECK-NOMOVW-NEXT: ldr {{r[0-9]+}}, [[[REG]], #124]
|
||
|
define i32 @mov32_range_start() {
|
||
|
entry:
|
||
|
%var = alloca i32, align 4
|
||
|
%arr = alloca [1148 x i8], align 4
|
||
|
%0 = load i32, ptr %var, align 4
|
||
|
ret i32 %0
|
||
|
}
|
||
|
|
||
|
; Here using an ldr offset doesn't save an add so we shouldn't do it.
|
||
|
; CHECK-LABEL: mov32_range_next:
|
||
|
; CHECK-MOVW: movw [[REG:r[0-9]+]], #1152
|
||
|
; CHECK-NOMOVW: movs [[REG:r[0-9]+]], #4
|
||
|
; CHECK-NOMOVW-NEXT: lsls [[REG]], [[REG]], #8
|
||
|
; CHECK-NOMOVW-NEXT: adds [[REG]], #128
|
||
|
; CHECK-NEXT: add [[REG]], sp
|
||
|
; CHECK-NEXT: ldr {{r[0-9]+}}, [[[REG]]]
|
||
|
define i32 @mov32_range_next() {
|
||
|
entry:
|
||
|
%var = alloca i32, align 4
|
||
|
%arr = alloca [1152 x i8], align 4
|
||
|
%0 = load i32, ptr %var, align 4
|
||
|
ret i32 %0
|
||
|
}
|
||
|
|
||
|
; Smallest offset where using an ldr offset prevents needing a movt or lsl+add
|
||
|
; CHECK-LABEL: can_clear_top_byte_start:
|
||
|
; CHECK: add sp, {{r[0-9]+}}
|
||
|
; CHECK-MOVW: movw [[REG:r[0-9]+]], #65412
|
||
|
; CHECK-NOMOVW: movs [[REG:r[0-9]+]], #255
|
||
|
; CHECK-NOMOVW-NEXT: lsls [[REG:r[0-9]+]], [[REG:r[0-9]+]], #8
|
||
|
; CHECK-NOMOVW-NEXT: adds [[REG:r[0-9]+]], #132
|
||
|
; CHECK-NEXT: add [[REG]], sp
|
||
|
; CHECK-NEXT: ldr {{r[0-9]+}}, [[[REG]], #124]
|
||
|
define i32 @can_clear_top_byte_start() {
|
||
|
entry:
|
||
|
%var = alloca i32, align 4
|
||
|
%arr = alloca [65536 x i8], align 4
|
||
|
%0 = load i32, ptr %var, align 4
|
||
|
ret i32 %0
|
||
|
}
|
||
|
|
||
|
; Largest offset where using an ldr offset prevents needing a movt or lsl+add
|
||
|
; CHECK-LABEL: can_clear_top_byte_end:
|
||
|
; CHECK: add sp, {{r[0-9]+}}
|
||
|
; CHECK-MOVW: movw [[REG:r[0-9]+]], #65532
|
||
|
; CHECK-NOMOVW: movs [[REG:r[0-9]+]], #255
|
||
|
; CHECK-NOMOVW-NEXT: lsls [[REG:r[0-9]+]], [[REG:r[0-9]+]], #8
|
||
|
; CHECK-NOMOVW-NEXT: adds [[REG:r[0-9]+]], #252
|
||
|
; CHECK-NEXT: add [[REG]], sp
|
||
|
; CHECK-NEXT: ldr {{r[0-9]+}}, [[[REG]], #124]
|
||
|
define i32 @can_clear_top_byte_end() {
|
||
|
entry:
|
||
|
%var = alloca i32, align 4
|
||
|
%arr = alloca [65656 x i8], align 4
|
||
|
%0 = load i32, ptr %var, align 4
|
||
|
ret i32 %0
|
||
|
}
|
||
|
|
||
|
; Smallest offset where using an ldr offset doesn't clear the top byte, though
|
||
|
; we can use an ldr offset if not using movt to save an add of the low byte.
|
||
|
; CHECK-LABEL: cant_clear_top_byte_start:
|
||
|
; CHECK: add sp, {{r[0-9]+}}
|
||
|
; CHECK-MOVW: movw [[REG:r[0-9]+]], #124
|
||
|
; CHECK-MOVW-NEXT: movt [[REG:r[0-9]+]], #1
|
||
|
; CHECK-NOMOVW: movs [[REG:r[0-9]+]], #1
|
||
|
; CHECK-NOMOVW-NEXT: lsls [[REG:r[0-9]+]], [[REG:r[0-9]+]], #16
|
||
|
; CHECK-NEXT: add [[REG]], sp
|
||
|
; CHECK-MOVW-NEXT: ldr {{r[0-9]+}}, [[[REG]]]
|
||
|
; CHECK-NOMOVW-NEXT: ldr {{r[0-9]+}}, [[[REG]], #124]
|
||
|
define i32 @cant_clear_top_byte_start() {
|
||
|
entry:
|
||
|
%var = alloca i32, align 4
|
||
|
%arr = alloca [65660 x i8], align 4
|
||
|
%0 = load i32, ptr %var, align 4
|
||
|
ret i32 %0
|
||
|
}
|
||
|
|
||
|
; An ldr offset doesn't help for anything, so we shouldn't do it.
|
||
|
; CHECK-LABEL: cant_clear_top_byte_next:
|
||
|
; CHECK: add sp, {{r[0-9]+}}
|
||
|
; CHECK-MOVW: movw [[REG:r[0-9]+]], #128
|
||
|
; CHECK-MOVW: movt [[REG:r[0-9]+]], #1
|
||
|
; CHECK-NOMOVW: movs [[REG:r[0-9]+]], #1
|
||
|
; CHECK-NOMOVW-NEXT: lsls [[REG:r[0-9]+]], [[REG:r[0-9]+]], #16
|
||
|
; CHECK-NOMOVW-NEXT: adds [[REG:r[0-9]+]], #128
|
||
|
; CHECK-NEXT: add [[REG]], sp
|
||
|
; CHECK-NEXT: ldr {{r[0-9]+}}, [[[REG]]]
|
||
|
define i32 @cant_clear_top_byte_next() {
|
||
|
entry:
|
||
|
%var = alloca i32, align 4
|
||
|
%arr = alloca [65664 x i8], align 4
|
||
|
%0 = load i32, ptr %var, align 4
|
||
|
ret i32 %0
|
||
|
}
|