SH7751 Group, SH7751R Group
Section 2 Programming Model
R01UH0457EJ0301 Rev. 3.01
Page 53 of 1128
Sep 24, 2013
2.2.3
Floating-Point Registers
Figure 2.4 shows the floating-point registers. There are thirty-two 32-bit floating-point registers,
divided into two banks (FPR0_BANK0–FPR15_BANK0 and FPR0_BANK1–FPR15_BANK1).
These 32 registers are referenced as FR0–FR15, DR0/2/4/6/8/10/12/14, FV0/4/8/12, XF0–XF15,
XD0/2/4/6/8/10/12/14, or XMTRX. The correspondence between FPRn_BANKi and the reference
name is determined by the FR bit in FPSCR (see figure 2.4).
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Floating-point registers, FPRn_BANKi (32 registers)
FPR0_BANK0, FPR1_BANK0, FPR2_BANK0, FPR3_BANK0, FPR4_BANK0,
FPR5_BANK0, FPR6_BANK0, FPR7_BANK0, FPR8_BANK0, FPR9_BANK0,
FPR10_BANK0, FPR11_BANK0, FPR12_BANK0, FPR13_BANK0, FPR14_BANK0,
FPR15_BANK0
FPR0_BANK1, FPR1_BANK1, FPR2_BANK1, FPR3_BANK1, FPR4_BANK1,
FPR5_BANK1, FPR6_BANK1, FPR7_BANK1, FPR8_BANK1, FPR9_BANK1,
FPR10_BANK1, FPR11_BANK1, FPR12_BANK1, FPR13_BANK1, FPR14_BANK1,
FPR15_BANK1
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Single-precision floating-point registers, FRi (16 registers)
When FPSCR.FR = 0, FR0–FR15 are assigned to FPR0_BANK0–FPR15_BANK0.
When FPSCR.FR = 1, FR0–FR15 are assigned to FPR0_BANK1–FPR15_BANK1.
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Double-precision floating-point registers or single-precision floating-point register pairs, DRi
(8 registers): A DR register comprises two FR registers.
DR0 = {FR0, FR1}, DR2 = {FR2, FR3}, DR4 = {FR4, FR5}, DR6 = {FR6, FR7},
DR8 = {FR8, FR9}, DR10 = {FR10, FR11}, DR12 = {FR12, FR13}, DR14 = {FR14, FR15}
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Single-precision floating-point vector registers, FVi (4 registers): An FV register comprises
four FR registers
FV0 = {FR0, FR1, FR2, FR3}, FV4 = {FR4, FR5, FR6, FR7},
FV8 = {FR8, FR9, FR10, FR11}, FV12 = {FR12, FR13, FR14, FR15}
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Single-precision floating-point extended registers, XFi (16 registers)
When FPSCR.FR = 0, XF0–XF15 are assigned to FPR0_BANK1–FPR15_BANK1.
When FPSCR.FR = 1, XF0–XF15 are assigned to FPR0_BANK0–FPR15_BANK0.
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Single-precision floating-point extended register pairs, XDi (8 registers): An XD register
comprises two XF registers